REU STUDENT ABSTRACTS

The Effects of Deglaciation and Other Environmental Variables on Alpine Plant Richness and Dominant Species

Matt Callahan 2009 REU Student at University of Alaska Southeast
REU mentor: Dr. Sanjay Pyare, University of Alaska Southeast, Juneau, AK

ABSTRACT
Areas where glaciers are receding in the face of climate change are ideal opportunities to study plant colonization, succession and patterns of plant diversity. We studied alpine plant communities in Southeast Alaska to establish whether time since deglaciation and other broad scale environmental variables related to climate change affect plant richness. We also identified dominant species in these communities to study basic patterns of primary succession near glaciers. Deglaciation was measured by distance to glacier boundaries in 1997 as well as estimates of negative vertical surface change over the last 50 years. We surveyed alpine vegetation at seven sites near Juneau, Alaska. We mapped sites based on deviation from average values of wind, surface change, slope angle, slope aspect, precipitation and elevation, and selected sites to represent a range of environmental conditions. At each site we estimated the percent coverage of each plant species in ten plots. We found no correlation between distance to glaciers or any other environmental variable and plant richness. No variable predicted dominant species with the exception of areas dominated by Vaccinium alaskaense (Alaska blueberry). These were closer to glaciers and had several other unique environmental characteristics relative to other dominant species. More data are needed to draw conclusions on the impact of these environmental factors on plant distributions and communities. Any effects of deglaciation on plant communities would best be studied by long term monitoring.

METABOLIC CONSEQUENCES OF HEMATODINIUM INFECTION IN FEMALE TANNER CRAB (CHIONOECETES BAIRDI): FURTHER INSIGHT INTO BITTER CRAB SYNDROME

Veronica Chaidez, 2009 REU Student at University of Alaska Southeast
REU Mentor: Dr. Sherry Tamone, University of Alaska Southeast, Juneau, AK

ABSTRACT
Tanner crab populations in Southeast Alaska are affected by bitter crab syndrome (BCS) caused by a parasitic dinoflagellate Hematodinium sp. Prevalence of the disease can approach 100% in certain populations of crab in Alaska. The purpose of this study was to better understand the metabolic cost of a Hematodinium infection on Tanner crabs by measuring glucose concentrations. Our hypothesis was that glucose levels would be lower in infected crabs than in uninfected crabs. Crabs were collected in Auke Bay, Alaska using baited crab pots soaked for 24-hours at depths of 20-30 meters. Both multiparous (n=21) and primiparous (n=26) Tanner crabs were collected. Crabs were returned live to the laboratory where they were maintained in ambient seawater and fed regularly. After one week of acclimation, initial hemolymph samples were withdrawn, blood smears for BCS detection prepared, and glucose concentrations measured. All multiparous crabs were free of BCS whereas all primiparous crabs were infected with BCS. Eyestalk ablation was performed on both groups and hemolymph was sampled every three days after that for nine days. After eyestalk ablation, 88% of the primiparous crabs died within three days. In contrast, 14% of the multiparous crabs died within three days. Glucose concentrations were significantly lower after nine days in the uninfected group, 3.04 ± 1.8 mg/dl compared to 2.05 ± 1.2 mg/dl. Glucose concentrations were significantly higher after nine days in the infected group, 2.92 ± 0.9 mg/dl compared to 10.13 ± 2.0 mg/dl.

 DISTRIBUTION AND INFECTION PATTERNS OF A CHYTRID FUNGUS AFFECTING BOREAL TOADS OF SOUTHEAST ALASKA

Catherine F. Frock, University of Alaska Southeast, 2009 REU Summer  StudentMentor: Dr. Jennifer  Moore, Postdoctoral researcher, University of Alaska SE, Juneau, AK

 ABSTRACT
Amphibians throughout the world are suffering from the emergent disease chytridiomycosis, which is caused by the recently-discovered fungal pathogen, Batrachochytrium dendrobatidis (Bd). The boreal toad (Bufo boreas boreas) is known to be susceptible to Bd, and cases of chytrid infection in southeast Alaska recently have been documented in this species. To contribute to the existing body of knowledge on the occurrence and distribution of Bd on a global, as well as local, scale, sampling of boreal toads was conducted in locations around southeast Alaska with various degrees of habitat modification: Haines, Admiralty Island, and the Juneau-Douglas area. Toads were opportunistically sampled during surveys of approximately 50 known breeding sites. Individual data were collected (snout-to-vent length, mass, life history stage, photo ID)as well as habitat information (GPS coordinates, brief site description, water temperature, pH).  Skin swabs were PCR-tested for the presence of Bd Twenty-three percent of the samples (n=13) tested positive for chytrid fungus. Two of these samples were obtained in Haines, one from a toad sampled near Chilkoot Lake and the other from a toad found near Chilkat River. The location of the third positive sample is questionable due to an error in data collection. When combined with results from previous chytrid sampling efforts in 2007, these data will be examined from a GIS perspective to provide information on ecological and landscape factors which may be affecting chytrid fungus infection patterns. Since disease is one of several key reasons for amphibian declines, this knowledge is beneficial to future conservation efforts undertaken in dynamic and fragmented landscapes.

Patterns of Size of Smolting Chum Salmon (Oncorhychus keta) Using Different Habitats within the Fox River Estuary, Alaska

Michelle Gutsch, University of Alaska Southeast, REU Summer 2009 Student REU Mentor: Tammy Hoem, University of Alaska Fairbanks Graduate Student, Homer, AK

ABSTRACT
Diversity in body sizes among populations of salmon contributes to their ability to survive in varying environments.  Little is known about how juvenile salmon use estuarine habitats, particularly in northern latitudes; by examining juvenile chum salmon in the Fox River estuary we can study them during an important part of their life cycle and find ways to preserve vital habitats that are key to their persistence.  Our goal was to examine the diversity of the estuarine habitats and how they contribute to the resilience of chum salmon populations. We sampled ten sites composed of four different channel types over six weeks and examined the data.  Our results demonstrate that a diversity of habitats exist within the estuary with regards to conductivity, temperature, and depth.  Also, sizes of chum salmon were found to be significantly different over time and between sites.  This diversity contributes to their ability to survive over long periods of time in changing environments.  Future work should include developing a clearer understanding of the entire range of life history characteristics expressed in chum salmon in the Fox River Estuary, from their freshwater incubation stage to spawning adult stage to determine the best management approach to protect these amazingly dynamic northern latitude ecosystems.

DOES AN ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA) DETECT PROGESTERONE IN BLUBBER FROM PREGNANT HUMPBACK WHALES (MEGAPTERA NOVAEANGLIA)?

Nicole Z. Jensen1, Sherry L. Tamone2, Elizabeth A. Mathews2
1 University of Alaska Southeast, REU Summer 2009 student
2 REU Mentor, Associate Professor, Department of Natural Sciences, University of Alaska SE

ABSTRACT
Birth rates and pregnancy status are important tools for monitoring the population dynamics of mammals.  Progesterone, an important reproductive hormone, is found in high concentrations during gestation in placental mammals and has recently been shown to be detectable in the blubber of whales. We set out to measure progesterone levels in blubber from humpback whales with an enzyme-linked immunosorbent assay (ELISA). Blubber samples (n=36) were collected by a colleague from living, individually identified humpback whales in the Hawaiian breeding grounds with a biopsy dart system. A whale's gender was determined genetically from skin portions of each biopsy; 14 were from females. Using published life history data (e.g., age of first pregnancy, mean birth interval, etc.) for humpback whales, we estimated how many of the 14 samples would likely be from pregnant animals assuming random sampling. Our prediction was that 4-6 of the samples should be from pregnant females; however we have not yet incorporated a month-of-collection correction. We extracted the progesterone using published methods and ran an ELISA with antibodies specific to this steroid hormone. We compared the absorbance readings and concentrations of progesterone and plotted our results on our standard curve for progesterone. Of the 36 samples, 11 showed levels of progesterone so high that they were off the sensitivity scale of the standard curve. Of these 11, 6 were from males and 5 were from females. Basic biology says that males should not have high progesterone levels. It appears likely that some molecule interfered with the ELISA, giving false positives. We performed another extraction with male blubber spiked with known levels of progesterone, and again, our extraction efficiency or ELISA were unreliable. More extractions and ELISAs will be run to gain confidence in our methods before testing more samples of blubber with unknown progesterone levels.

THE EFFECT OF WATERSHED GLACIAL COVERAGE ON STREAM BIOGEOCHEMISTRY

Andrew Jeffery, University of Alaska Southeast, REU Summer 2009 Student
REU Mentor: Eran Hood, PhD, University of Alaska Southeast, Juneau, AK

 ABSTRACT
Glacier recession in coastal, maritime environments contributes large volumes of runoff to near-shore watersheds and marine ecosystems.  This has profound hydrologic and biochemical implications for in-stream processes.  The objectives of this study were to determine the impact of varying degrees of glacier coverage on biogeochemical properties in three coastal watersheds located within the Juneau road system of Southeast Alaska.  The three studied watersheds have glacial coverages of 0, 24, and 43 percent with similar lithology, high elevation alpine tundra, and low elevation, evergreen forests.  Longitudinal sampling was performed by collecting samples along the length of each watershed from the stream headwaters to the watershed outlet.  Sampling points in between the source and outlet were chosen downstream of major tributaries to allow input from forested and wetland land covers.  Each sample was then run for dissolved organic carbon, total nitrogen, and ultraviolet absorbance.  Temperature and specific conductivity were significantly different in all three watersheds with the intermediately covered watershed (24 %) having the largest increase and range of values (0.39-5.35 °C and 12.3-24.6 mS/cm).  Dissolved organic carbon concentrations were both significantly lower in the glaciated watersheds, again with the intermediately covered watershed experiencing the largest increase (0.20-0.68 mg C/L).  Specific ultraviolet absorbance showed an increasing trend in all watersheds, with more pronounced increases in the glaciated watersheds.  These results show that the intermediately covered watershed has the largest range of physical and biogeochemical properties, offering diverse habitat conditions for aquatic organisms.  They also show a decrease in reactivity along the length of the watershed, indicating glaciers as a possible source of bioavailable nutrients.

INFLUENCE OF BACKGROUND COLOR MATCHING BY COASTRANGE SCULPIN MODELS ON PREDATOR ATTACK FREQUENCY

Tyler Linderoth, University of Alaska Southeast, REU Summer 2009 student
REU Mentor: Carolyn Bergstrom, Department of Natural Sciences, University of Alaska Southeast, Juneau, AK

ABSTRACT
Coastrange sculpin (Cottus aleuticus) match the substrate color of their streams and are highly variable in color both within and among populations. We investigated the benefits of color crypsis by testing the hypothesis that background color matching by coastrange sculpin reduces the frequency of attack by visual predators. To test this we used four different coastrange sculpin clay model treatments: light clay fish on a light boulder background, light clay fish on a dark boulder background, dark clay fish on a light boulder background, and dark clay fish on a dark boulder background. Forty sculpin models, 10 of each treatment, were mounted onto alumacore plates that featured a standardized substrate image. We quantified the degree of contrast (background matching value) for each treatment with digital photography. We deployed the models twice in both Auke Creek and Salmon Creek in Juneau, Alaska, and scored them for predator attack marks left in the clay. The frequency of predation was highly significantly different among treatments and a positive relationship existed between the degree of contrast of the model on its plate and the frequency at which treatments were attacked. The frequency of predation was not significantly different between sculpin model colors alone but was significantly different between plate colors. However, when I omitted the treatment with the greatest contrast that was suspected of influencing the significant two-way effect of predation and plate color, the difference between plate colors became non-significant as did the difference among the three remaining treatments. Our study demonstrated that the ability to match background color by coastrange sculpin reduces the frequency of attack by visual predators, and suggests this trait may be a target of selection in wild populations.

 INFLUENCE OF ENVIRONMENTAL VARIABLES ON TREELINE ELEVATION IN SUBALPINE-ALPINE ECOSYSTEMS

Sarah Machacek, University of Alaska Southeast, REU Summer 2009 Student
REU Mentor: Sanjay Pyare, Assistant Professor, University of Alaska Southeast, Juneau, AK

 ABSTRACT
Treeline advance in the subalpine-alpine environment is a strong indicator of global climate change. Because there are several environmental variables indirectly and directly related to climate change that may affect treeline advance, we conducted a study to determine which variables predominantly contribute to treeline elevation. Using GIS , we modeled six broad-scale factors as potential contributors to treeline movement: wind intensity, annual precipitation, slope angle, slope aspect, recent surface (glacier) change, and distance to glacier. We scored potential sampling sites based on deviations from average values of environmental conditions at respective locations, and then selected a subset of these sites to ensure a sample with a large range of environmental conditions.. We visited 19 sites and marked actual treeline elevations using a GPS. We performed simple regressions for each environmental variable and treeline elevation. We found a positive correlation between treeline elevation and wind intensity. These results were counter-intuitive because wind intensity is known to cause higher mortality among trees, and thus stronger wind is not likely to be associated with a higher treeline.  We also found a lack of correlation between treeline elevation and slope aspect, which was also surprising given it is well-established that south-facing slopes in the Northern Hemisphere have higher sun exposure and therefore higher treelines. Our sample size, however, was limited and further data collection is needed to more adequately test for correlations between treeline elevation and these variables.

Determining Organotin Levels, a Component of Anti-fouling Paint, in Subsistence-Use Shellfish in Hoonah, Alaska

Rose C. Stanley, UAS REU Summer 2009 Student
REU Mentor: Dr. Lisa Hoferkamp, UAS

ABSTRACT
The hulls of cruise ships and other large marine vessels are treated with anti-fouling paint to prevent the growth of marine organisms. Synthetic compounds, based on a central tin (IV) ion to which is bonded various alkyl or aromatic hydrocarbon groups, are the active components of these paints (collectively known as organotin compounds), with tributyltin (TBT) the most toxic among them.  Organotins have been linked to deleterious effects in non-target organisms including reproductive abnormalities such as imposex in file dogwhelks.  In Hoonah, Alaska subsistence users harvest shellfish including mussels, clams and cockles from the surrounding waters.  In 2004, cruise ships began docking in Hoonah and have possibly introduced a source of TBT and other organotin compounds into the historically pristine marine ecosystem. We evaluated levels of the organotin compounds tributyltin, monobutlytin, dibutyltin and triphenyltin in mussel, clam and cockle samples donated from the 2008 subsistence collection of Hoonah, AK.  Organotin compounds were chemically extracted from the shellfish tissue and extracts were analyzed by gas chromatography coupled with mass spectrometry.  Quantification of organotin levels was complicated, presumably by the introduction of phthalates from plastic labware, however low, but non-zero levels of TBT have been confirmed.  Future work will include further purification of the tissue extracts and re-analysis for final quantification.

INFLUENCE OF SUBSTRATE COLOR ON THE PREDATORY RESPONSE OF COAST RANGE SCULPIN FROM GLACIER BAY

Dinorah Chacin, University of Alaska Southeast, REU Summer 2007 Student
Florida International University, Miami, Florida.

REU Mentor:  Andrew Whiteley, University of Alaska Southeast, Juneau, Alaska.

ABSTRACT
As landscapes quickly change in Glacier Bay, Alaska, ice sheets recede and the formation of new rivers occurs; as a consequence new organisms colonize and are likely to develop different adaptive responses. Coastrange sculpins (Cottus aleuticus) have colonized new streams following glacial recession in Glacier Bay, Alaska. In our study we assessed the question of whether behavior and cryptic coloration of sculpins were adaptive traits that have developed in the last 200 years. Other studies have shown that animals that use cryptic coloration to avoid predators remain immobile to evade detection. Based on that observation we hypothesized that sculpins behavior would differ depending on the substrate color where they are placed and on whether or not a predator was present.
To test our hypothesis we used three predation treatments where 1) predatory Dolly Varden (Salvelinus malma) char were present, 2) only Dolly Varden scent was present, and 3) a control.  In addition, we used two substrate color treatments to resemble either newer streams (mostly white substrate) or older streams (mostly green substrate). We observed a significant reduction of movement rates when the predator was present relative to the scent only and control treatments.  However, the effect of substrate color treatment was not significant. The lack of behavioral difference between substrate color treatments upon the introduction of the predators suggests that adaptive behavioral differences do not occur between the two populations tested.  However, observed fish color differences may still provide an adaptive advantage independent of movement behavior and this should be the focus of future research

 ARCTIC AND ALEUTIAN TERN NEST DIFFERENTIATION IN YAKUTAT, ALASKA

Derek DeRaps, University of Alaska Southeast, REU Summer 2008 Student
Georgia Institute of Technology, Atlanta, GA

REU Mentor: Mike Goldstein, US Forest Service, Juneau, AK

ABSTRACT
Recent aerial surveys suggest Aleutian Tern populations have declined 50-95% in Alaska, but the accuracy of these claims remains uncertain as past studies were inconsistent in their application and methodology.  To address this problem the USFS, ADF&G, and UAS are developing a reliable and repeatable ALTE colony breeding population estimation technique.  Mixed-species colonies present a confounding factor to the sampling methods.  When more than one species inhabits a colony and nests cannot be easily distinguished, a ratio of the two tern species in the colony will help provide single-species population estimates.  Arctic and Aleutian Tern nests share too many morphological characteristics to allow for confident species identification with a visual assessment.  To find distinguishing nest characteristics, I measured 50 nest variables at 40 Aleutian Tern and 45 Arctic Tern nests; nine variables were found to differ significantly between species (one-way ANOVA; p<0.001).  I developed a stepwise model using a discriminant function analysis with six of those variables, which resulted in 93% nest-identification accuracy.  I then developed an efficient ratio estimator to be tested at other colonies and used with future survey efforts.

Fecundity, Egg Viability and Associated Sampling Methods of Red King Crab (Paralithodes camtschatica) in Southeast Alaska

Thomas John Fayton, University of Alaska Southeast, REU Summer 2008 Student, Vassar College

REU Mentor:  Joel Webb, Alaska Department of Fish and Game

ABSTRACT
A 2006 Southeastern Alaska Red King Crab (RKC) Stock Assessment Review recommended that the Alaska Department of Fish and Game (ADF&G) add an assessment goal of maintaining reproductive potential by establishing a fecundity-size relationship for RKC in SE Alaska and also by measuring egg clutch fertilization success. The objectives of this project were examine variability in the size-fecundity relationship and egg viability among survey areas in Southeast Alaska and to assess the relationship between laboratory estimates of fecundity and the visual assessment of the proportion of eggs to empty space under the abdominal flap or clutch fullness index  (CFI) collected on stock assessment surveys.  RKC clutches were collected to meet sampling goals by  size and CFI categories (80-100% - high; 30-70% - low) from four areas of Southeast Alaska: Deadman's Reach, Gambier Bay, Barlow Cove, and Pybus Bay. Dry weight methods were used to estimate fecundity, and the egg viability based on structure and color was examined for ~500 eggs per female.  The size-fecundity relationship for RKC in Southeast Alaska is approximately linear and the number of eggs per mm carapace length did not significantly differ among the four areas sampled (F=2.687, p= 0.0504).  Egg viability was high across all areas with a mean of 99.16% of eggs developing normally for each female.  Slopes (t=0.15, p>0.05, df=102) and elevations (t=0.29, p>0.05, df=99) of linear fits of the size-fecundity relationships of  the high and low CFI bins did not differ significantly suggesting that fine scale differences in fecundity may not be detected by visual estimation of clutch fullness. 

RETROSPECTIVE ANALYSIS OF SEX RATIO AND EGG PRODUCTION OF RED KING CRAB (PARALITHODES CAMTSCHATICA) IN SOUTHEAST ALASKA

Isaiah Iaea1, Joel Webb2, and Ginny Eckert3

1  University of Alaska Southeast, REU Summer 2008 Student, University of Hawai'I at Manoa
2  Alaska Department of Fish and Game, Juneau, Alaska
3  University of Alaska Southeast

ABSTRACT
A time series (1979-2006) of pot survey data from Alaska Department of Fish and Game was for examined for variability and correlation of sex ratio and female clutch fullness index (CFI) for the red king crab, Paralithodes camtschaticus.  A conservative approach was used analyze the relationship between the sex ratio of mature red king crab and the proportion of females with low CFI potentially due to a lack of males to mate with females and maintain fertilized egg production.  For analysis male and female crab were divided into categories by size and maturity status.   Males were with a carapace length (CL) 109-144 mm were classified as reproductively mature sublegals capable of mating but not harvested in the fishery ; males >145 mm were legal size.  Females with carapace length 100-128 mm were reproductively mature but of intermediate size and females with carapace length >129 mm classified as large matures.  Female clutch fullness index or a visual estimate of the relative fullness of the egg clutch taken during stock assessment surveys was organized into three different percent categories: 0-33, 34-66, and 67-100.  No significant correlations were found between a female-biased sex ratio of mature crabs and proportion of females with low percent clutch fullness index (< 66 %).   Neither was significant correlation observed between sex ratio of large females and legal males and low CFI.  These results suggest that in Southeast Alaska on a broad spatiotemporal scale sex ratio is not correlated with gross changes in egg production due to skewed sex ratios from either natural variability or fishery effects.  

Predator influence on snail recolonization in Auke Bay, Alaska

Rosemary Luzania, University of Alaska Southeast, REU Summer 2008 Student, California State University, Fresno CA

REU Mentor:  David Tallmon, University of Alaska Southeast, Juneau, AK

ABSTRACT
We sought to investigate the impact of predators on recolonizing populations of the file dogwinkle, Nucella lima, that were previously extinguished from Auke Bay Marina by tributyltin contamination.  We hypothesized that predators do not reduce survival of recolonizing snails, while avian and seastar predators reduce snail survival.  We set up predator exclusion cages in Auke Bay in which either bird predation, or bird and seastar predation, were prevented, and monitored snail survival each day during low tide.  Using a one-way analysis of variance, we calculated survival as the proportion of five snails that survived in each treatment (no birds, no birds or seastars, and controls).  There was no significant effect of predators on survival with a P = 0.159.  Our results refuted our expectations.  In a sealab experiment to investigate whether snails were leaving their treatment cages, we found emigration occurring.  From this we can conclude the lack of difference between treatments and control in our study may have been due to emigration of the animals.  Future work would include reducing emigration per cages by either building better cage fixtures or tethering the snails to the substrate. 

Crustacean Hyperglycemic Hormone and its Role in Glucose Regulation in Tanner Crabs (Chionoecetes bairdi)

Kevin McNeel, University of Alaska Southeast, REU Summer 2008 Student
University of Alaska Southeast, Juneau, Alaska

REU Mentor: Sherry Tamone, University of Alaska Southeast, Juneau, Alaska

To efficiently use glucose in a potentially nutrient limited environment, organisms need to conserve and access energy at the appropriate time. Understanding the normal cues (hormonal and environmental) that regulate metabolism is important in assessing potential changes in animal metabolic physiology as a function of changes in environmental conditions. The sinus gland in the crustacean eyestalk is known to regulate hemolymph glucose concentrations by secreting neurohormones such as the crustacean hyperglycemic hormone (CHH). Tanner crab (Chionoecetes bairdi) CHH has been purified and its amino acid sequenced, but the bioactivity of purified CHH has not yet been quantified. Tanner crabs were collected in southeast Alaska off of Spuhn Island for use in a CHH bioassay in which the effect of CHH on circulating glucose was examined. We looked at the importance of the sinus gland and CHH in regulating glucose levels using eyestalk ablation and a sinus gland injection bioassay. Sinus glands (0, 0.5, 1.0, and 2) were injected into previously eyestalk ablated Tanner crabs.  Hemolymph was analyzed for glucose concentration before and 120 minutes after injection using Sigma glucose assay. Analysis of hemolymph taken before and after one week of eyestalk ablation found that eyestalk ablation significantly decreased blood glucose concentration with a mean decrease of 9.3 ± 0.5 μg/ μl. The sinus gland bioassay showed no significant difference between sinus gland injections and the control (no SG). The results of the study may have been affected by the induction of late stages of the parasite Hematodinium spp in all crabs that were eyestalk ablated. Also, the large mortality event caused by bitter crab sporulation suggests that eyestalk ablation may induce the later life stage and infection of the parasitic dinoflagellate.     

The Concentration of  Tributlytin in local Marine Habitats and the Effects on Nucella lima

Ge'Yanni Polk  University of Alaska Southeast, REU Summer 2008 Student
California Polytechnique University, Pomona, Ca

REU Mentor: Dr Lisa Hoferkamp, University of Alaska Southeast, Juneau, AK

ABSTRACT
The population of Nucella lima have decreased in many marine coastal area's of Alaska. One hypothesis for the decrease of Nucella lima is the introduction of tributlytin (TBT) into these once pristine areas. TBT is an organotin compound, that is toxic to many marine organisms, especially Nucella lima. TBT toxicity is known to induce imposex in  Nucella lima. The environmentally forced sexual change, reduces the number of Nucella lima in the area. Significant TBT concentrations are common in coastal areas with heavy boating traffic, especially large commercial vessels. The larger ships are coated with anti-fouling paint that contains TBT as an active ingredient which inhibits the attachment of barnacles to the exterior of the ships. Mussel tissue serves as one of the main feeding sources for the carnivorous snails and thus was used as an indicator for TBT presence.  Samples of mussel tissue were collected from Alaskan coastal areas subject to large, moderate and very limited marine vessel traffic.  Acidic extraction of the tissues followed by analysis via Graphite Furnace Atomic Absorption Spectrometry (GFAAS) was used to determine TBT and total tin concentrations in extracted mussel tissue at parts per billion levels. Future work should continue the monitoring of TBT and total tin in coastal marine areas so that assessments of declines in Nucella lima populations can include this contaminant factor.  

Attenuation of Polybrominated Diphenyl Ethers (PBDEs) From Abiotic Processes Characteristic to Southeast Alaska Environments

Steffi Schreiber, University of Alaska Southeast, REU Summer 2008 Student
University of Alaska Southeast, Juneau, Alaska

REU Mentor: Lisa Hoferkamp, University of Alaska Southeast, Juneau, Alaska

ABSTRACT
PBDEs, a class of brominated flame retardants, are used in many consumer products. Due to their persistence in the environment, their tendency to bioaccumulate, their potential for long range atmospheric transport, and their toxicity to biological systems industrial mixtures containing 5 to 8 bromines have been banned from production. However, the fully brominated BDE209 is still used by the industry. In this project we investigated the attenuation, via reductive dehalogenation, of BDE209 in an anaerobic wetland system with high concentrations of reduced iron (Fe2+). In addition to indicating attenuation products the experimental design also allowed us to obtain information regarding the role of Fe2+ and surface interactions in the reductive process. We assembled a series of batch slurries in sealed serum bottles, each series in triplicate. One set of batch slurries imitated typical Southeast Alaska wetland conditions containing water and sediment from a local wetland site. In a second series we assembled site water, sediment and Na3N in order to determine microbial influence. Control batch sets consisted of sterile lab sand with site water as well as slurries containing only site water. We added BDE209 to all sets. After ~14 days of sample agitation we extracted the contents of the batch slurries. We determined the amount of BDE209 and the dominant attenuation products in the extracts using GC/MS. In addition to BDE209, we identified 4 lesser brominated products, suggesting a general degradation pathway for BDE209. Samples with significant [Fe2+] (~10ppm) showed measureable decomposition of BDE209 while those with nominal [Fe2+] did not thus indicating that reduced iron drives the kinetics of PBDE reduction. BDE209 debromination was also more pronounced in systems where surface mediation was possible further suggesting the role of surface-bound Fe2+. These preliminary findings will be used in future investigations into the natural attenuation of BDE209

THE EFFECTS OF OCEAN ACIDIFICATION ON LYRE CRAB HYAS LYRATUS METABOLIC PROCESSES

Sherry Tamone1 and Elena Fernandez2

1 REU Mentor, University of Alaska Southeast, Natural Sciences Department, Juneau, Alaska
2 University of Alaska Southeast, REU 2007 Student and Kenyon College, Gambier, OH

ABSTRACT
Recent studies indicate that increasing amounts of atmospheric CO2 dissolving into the ocean biome are causing acidification of the marine environment.  Some predictive oceanographic models indicate that pH will drop up to 0.5 pH units over the next 100 years. It is well documented that ocean acidification inhibits the ability of organisms to form and maintain calcium carbonate structures.  Examples of such organisms are diatoms, mollusks, and crustaceans.  The physiological cost to crustaceans that must regulate internal pH and must form a calcareous exoskeleton during each larval, juvenile and adult molt cycle remains unclear.  We measured standard metabolic rates of   female lyre crabs, Hyas lyratus that were acclimated for one week at pH 8, pH 7.5, pH 7.0, and pH 6.5. Metabolic rates were significantly different between crabs held at pH 8 and pH 6.5 (0.55 vs. 0.43 ml O2/kg/min).  Enzymatic rates of lactate dehydrogenase (LDH), pyruvate kinase, and citrate synthase decreased significantly with decreased pH.  This decreased activity of LDH could be detrimental to physiological processes that require anaerobic metabolism.  In fact, increased mortality was observed in crabs that were acclimated to pH 7.5, pH 7.0 and pH 6.5 and exposed to hypoxia for 24 hours when compared with control crabs held at pH 8.0.  It is likely that there is an energetic cost to crabs associated with ocean acidification and that this cost could have a negative impact on energetically costly physiological processes such as growth and reproduction.

HABITAT PREFERENCES OF JUVENILE RED KING CRAB (PARALITHODES CAMTSCHATICUS)

Jennifer E. Granneman1, Ginny Eckert2, and Jodi Pirtle3

1 University of Alaska Southeast, REU 2007 Student and California State University Long Beach
2 REU Student Mentor, Department of Natural Sciences, University of Alaska Southeast 
3 University of Alaska Fairbanks, School of Fisheries and Ocean Sciences

ABSTRACT
The behavior of juvenile red king crabs, Paralithodes camtschaticus, especially regarding preferred habitat, is not well understood.  The association of juvenile P. camtshcaticus with structurally complex invertebrates has been repeatedly observed in the field.  Structure forming invertebrates are thought to act as a nursery habitat by providing red king crabs protection from predation and perhaps increasing foraging success.  We hypothesized that juvenile P. camtschaticus significantly prefer structurally complex biogenic habitat more than complex physical substrate and habitat lacking any structure, especially when in the presence of a predator.  A habitat preferences experiment was conducted by placing juvenile P. camtschaticus approximately 1-1.5 years old into aquaria with each half of the aquaria devoted to one of the following experimental treatments: cobble, shell hash, tube worms (Serpula columbiana), anemones (Anthopleura artemisia), sand, kelp (Agarum clathratum), and dish scrubbers.  All possible combinations between these experimental treatments were tested in the presence and absence of a predator and the preferred position of the crab in the aquarium recorded after two hours.  In the experimental lab manipulations there was a significant difference in habitat preference of juvenile P. camtschaticus among the experimental treatments (p<0.001), but no significant effect of predator presence on habitat choice (p>0.05).  Juvenile red king crab associated preferentially with kelp, tube worms, and anemones respectively with sand being the least preferred substrate.  Surveys of the nearshore environment at nine sites in Juneau and Sitka were conducted by SCUBA divers at 20-40ft to determine the distribution and preferred habitat of juvenile P. camtschaticus.  Only two juvenile red king crab which were associated with kelp were observed, likely because P. camtschaticus juveniles are cryptic and in low density.  In conclusion, red king crab juveniles significantly prefer structurally complex biogenic habitat such as kelp more than low complexity habitat.

COMPARING KELP COMMUNITIES ON THE INNER AND OUTER COASTS OF SOUTHEAST ALASKA

Sonia N. Ibarra1 and Jodi L. Pirtle 2

1 University of Alaska Southeast, REU 2007 Student and Humboldt State University, Arcata, CA
2  REU Co-mentor, University of Alaska Fairbanks, School of Fisheries & Ocean Sciences, Juneau,AK

REU Mentor: Dr. Ginny Eckert, Natural Sciences, University of Alaska Southeast

ABSTRACT
Variation in physical and biological processes in coastal ecosystems determines kelp productivity and influences community structure. Identifying regional patterns of community structure is necessary to interpret coastal ecosystem response to climate change. We compared kelp communities on the inside coast of southeast Alaska near Juneau, and the outer coast near Sitka. Greater seawater exchange and reduced freshwater runoff at the outer coast may result in greater kelp abundance, density, and diversity; however kelp communities have not been comparatively studied between subregions of southeast Alaska. Kelp communities were surveyed at nine sites in each location using SCUBA transects at 6 m and 12 m depths to characterize physical habitats, and quantify kelps. Water quality parameters were measured using a CTD. Kelp abundance was greater at 6 m in both locations, but there was no significant difference in kelp abundance or density between locations. Species richness and diversity were greater on the outer coast, although community evenness was similar between locations. Patterns of kelp community structure are evident within and between these coastal subregions of southeast Alaska.

Modeling Glacial Runoff: Case Study of Lemon Glacier

Joshua Jones University of Alaska SE, REU 2007 Student and UAS Biology MajorREU Mentors: Drs. Eran Hood and Matt Heavner, Natural Sciences, University of Alaska Southeast

ABSTRACT
Glacial runoff is important in many areas of the world as a water resource; thus modeling runoff is an important tool for managing water resources.  In this study, a temperature index melt model that includes direct radiation was employed to simulate Lemon Glacier's contribution to the discharge of Lemon Creek near Juneau, Alaska.  This model was set to run in daily time steps on an indexed temperature gradient incorporating topographical shading calculations derived from a digital elevation model (DEMs).  The inputs required for the melt model include: continuous data for temperature and precipitation during the time of the model run, a digital elevation model of the glacier watershed, including the glacier surface area itself,  and information about the initial surface conditions such as depth of initial snow cover in water equivalent.  The model output include: discharge information given as daily totals and split as daily totals from the firn, snow, and ice reservoirs; mass balance data distributed over the whole glacier and at specified ablation stake coordinates; images of surface condition changes on a daily time scale; daily amounts of snow and ice melt images in millimeters; and depth of snow cover remaining in water equivalent for each time step.  The information output by the model has several useful applications.  One of these is calculating the contributions of snow melt and glacial runoff to discharge in Lemon Creek.  The volume of supra-glacial lakes on Lemon Glacier can also be estimated after outburst events by subtracting the modeled discharge from the measured discharge during the time of the outburst.  in the future, we hope to apply the melt model to other Juneau-area glaciers, couple the model with glacial recession models as the model does not currently account for changes in glacial surface area, and combine data from climate change models with the melt model for predicting the effects of a changing climate on glacial runoff.

ESTIMATING ABUNDANCE AND FACTORS AFFECTING SURVIVAL OF SCULPIN IN AUKE CREEK

Erik Lokensgard1, Andrew Whiteley2, and David Tallmon3

1 University of Alaska Southeast REU Student, 2007 and University of Chicago, Illinois
2 REU Student Mentor, Natural Sciences Division, University of Alaska SE,
International Polar Year (IPY) Post-doc
3 REU Student Mentor, Natural Sciences Division, University of Alaska Southeast

ABSTRACT
Polar areas are rapidly changing and survival of some species may depend upon rapid adaptation. Knowing whether a species is adapting - and if so, determining the rate of adaptation - will help to forecast extinction or to determine conservation efforts necessary to conserve biodiversity. As glaciers recede, streams form and may be colonized by sculpin, which exhibit phenotypic plasticity in matching the color of substrate. We hypothesized that substrate matching in cryptic sculpin is an adaptive trait, correlated with survival. We initiated a mark-recapture study in Auke Creek on two species of sculpin, Cottus asper and Cottus aleuticus, to test whether survival was influenced by certain covariates in addition to substrate matching: species, down vs. upstream, length, and color. We captured, PIT tagged, and photographed sculpin on a control substrate to obtain covariate measurements.  The results from one capture session and two recapture sessions confirmed previous literature that C. asper is significantly larger than C. aleuticus and is more abundant downstream. We found evidence of constant survival [0.82 (reservations); SE: 0.02; 95% CI: 0.78-0.85] and detection  (0.87; SE: 0.02; 95% CI: 0.83-0.91) probabilities across species and reaches, and no support for models that included an effect of the covariates on sculpin survival. However, a one-way ANOVA revealed a significant difference (p=0.024) in mean Euclidean distance between C. asper (27.23; SE: 1.05; 95% CI: 25.15-29.31) and C. aleuticus (23.65; SE: 1.11; 95% CI: 21.46-25.85) across reaches. Thus, the two species either have different substrate matching abilities or different mean coloration. The Auke Creek study will continue to better determine the effect of covariates on survival. By noting a potentially adaptive trait of a particular species, monitoring survival in relation to the trait, and determining if adaptation is presently occurring, this study will enable us to better understand a species' response to a changing environment.

EFFECTS OF GLACIAL RUNOFF ON STREAM ECOSYSTEMS IN SOUTHEAST ALASKA  

Holly Moeller University of Alaska Southeast, REU 2007 Student and Rutgers, New Brunswick, NJ

REU Mentors:  Drs. Eran Hood and Matt Heavner, Environmental Sciences, University of Alaska Southeast, Juneau, AK

ABSTRACT
Southeast Alaskan glaciers are experiencing some of the largest recession rates on earth.  To understand how pro-glacial streams will change as earth's climate warms and glaciers recede and contribute less to streamflow, physical and biological characteristics were measured in streams with differing glacier coverage.  Physical characteristics were measured along longitudinal transects in glacial and non-glacial streams.  These surveys showed that glacially fed streams are colder and less conductive near the glacier and become progressively warmer and more conductive downstream due to additional non-glacial runoff and tributary inputs.  Visualization of these data using Google Earth reveals that non-glaciated streams have less extreme temperature and conductivity gradients than their glaciated counterparts. Across a series of three watersheds varying in glacier coverage from 0-25%, streamwater temperature and conductivity decreased as percent glacier coverage increased.  Biological characteristics were also measured, indicating that pelagic photosynthesis was undetectable, but pelagic respiration was uniform across watersheds (0.5 mg O2 L-1 d-1).  Benthic communities became less productive with increasing glacial coverage, with chlorophyll concentration (g/m2) and ash free dry mass (AFDM, mg/m2) decreasing as glacial coverage increased.  While invertebrate density decreased with increasing glacial coverage, the number of individuals increased.  However, in an inter-watershed comparison of Lemon Creek (25% glacial coverage) and nonglaciated tributary Canyon Creek, benthic chlorophyll and AFDM were higher in Lemon Creek but invertebrate population and diversity were greater in Canyon Creek.  This suggests the complexity of interactions in stream ecosystems, where invertebrate populations may suppress accumulation of benthic biomass and in turn be suppressed by other factors not considered in this study.  To promote transmission of these data to a global audience and allow scientists to visually compare watershed characteristics from remote locations, data displays from this study are being designed for the virtual earth tool Google Earth.

KELP CULTURE FOR ECOLOGICAL STUDIES

Michael Pantalos, University of Alaska SE, REU 2007 and University of New Brunswick, Canada
REU Mentor:  Dr. Ginny Eckert, University of Alaska Southeast, Juneau, AK

ABSTRACT
Small mesograzers may influence structural foundations of an ecosystem by grazing on microscopic kelp recruits.  This study attempted to estimate grazing impact based on observed densities of the archaeogastropod Margarites pupillus and its calculated per capita interaction strength on microscopic Agarum clathratum sporophytes.  Methods were planned for culture of A. clathratum to microscopic sporophytes, exposure to M. pupillus, and sampling for density determination.  Although initial trials showed rapid copious spore release, few spores were obtained from sori used for the study.  Sori immaturity was suspected, and spore release from sloughing and non-sloughing sori was compared.  No difference in spore densities released from the two sori conditions was found, and significant spore densities did not appear until several days after release induction.  Small quantities of spores were used to compare settlement between surface orientations, and significantly more gametophytes were found on horizontal than on vertical surfaces.  The challenges of variable spore release and accounting for differential settlement will need to be addressed in future studies of grazing effects on spores.

HABITAT ASSESSMENT OF THE COASTAL RIVER OTTER

Kat Sever1, Brett Addis2, and Sanjay Pyare3

1 REU Student 2007 University of Alaska SE, and Oklahoma State University, Stillwater, OK
2 REU Student 2007 University of Alaska SE and Whitman College, Walla Walla, WA
3 REU Mentor, University of Alaska Southeast, Natural Sciences Deptartment, AK

ABSTRACT
Populations of the coastal river otter (Lontra canadensis) could be more effectively monitored as an environmental indicator species if otter occurrence and habitat associations were better understood.  We, therefore, studied river otters near Juneau, Alaska to test the predictive capability of a large scale habitat suitability index (HSI) model and to better understand the microhabitat characteristics that river otters select for.  A HSI model was created using a geographic information system (GIS), and we selected random sites (n=24) and high probability sites (>95% HSI scores, n=21) at which to conduct surveys. We surveyed for latrine presence, shoreline topography (e.g. slope, aspect, substrate, distance to freshwater), and vegetation (e.g. overstory, understory, successional stage) along a 300 m-transect at each site.  We found that 19% of high probability sites contained latrines compared to 4% of the random sites and a latrine density of .635/km at high probability sites and .139/km at random sites.  A logistic regression using a forward stepwise selection procedure was conducted to identify any microhabitat variables (p≤0.05) that differed significantly between high probability and random locations.  Results imply that the HSI did discriminate fine scale habitat differences between 2 types of sites. Common topographic characteristics among found latrine sites (n=5) were large rock, bedrock, convex shoreline, steep slope (>40%), and adjacency to ocean.  Collectively, these results suggest that ground-based latrine surveys should be focused in areas associated with these characteristics and that future river otter habitat models could benefit from including these variables.

HABITAT ASSESSMENT OF THE COASTAL RIVER OTTER IN JUNEAU, ALASKA

Brett Addis1, Katherine Sever2, and Sanjay Pyare3

1 REU Student 2007 University of Alaska SE, and Oklahoma State University, Stillwater, OK
2 REU Student 2007 University of Alaska SE and Whitman College, Walla Walla, WA
3 REU Mentor, Department of Natural Sciences, University of Alaska Southeast, Juneau, AK

ABSTRACT
Very little is known about the habitat of the coastal river otter (Lontra canadensis) in Juneau, Alaska. As an indicator species, the population status of the coastal river otter has the potential to reflect the health of its associated ecosystem, and as such, information regarding its habitat is useful for ecological monitoring and land management efforts. In this study, we surveyed randomly selected and high probability shoreline transects in the Juneau area for otter latrine sites. We determined high probability latrine locations from a predictive High Suitability Index (HSI) model generated in ArcGIS from 9 microhabitat variables. Topographical and vegetative characteristics were measured at the midpoint of each 300-m transect, as well as at latrine locations. Because river otters transport marine-derived nutrients to terrestrial ecosystems, it is possible that the plant community composition at latrine sites may differ from nonlatrine sites. Therefore, we also recorded the dominant overstory and understory vegetation, forest successional stage and Diameter at Breast Height (DBH) of a random selection of 10 trees in order to determine which vegetative characteristics otters select for and possible differences in plant community composition between latrine and nonlatrine locations. Logistic regression with a forward stepwise procedure revealed that the HSI model was successful in discriminating at least 3 microhabitat characteristics between high probability and random sites: substrate type, shoreline configuration, and aspect. There were no significant differences in vegetation between random and high probability sites, so future survey efforts need to incorporate more detailed information regarding vegetation into the HSI model.

Effect of Methyl Farnesoate on Female Cancer magister Y-organs

Lindsey S. Smith1 and Sherry Tamone2

1 University of Alaska Southeast, REU Summer 2007
2 REU Student Mentor, Natural Sciences Division, University of Alaska SE, Juneau, AK

ABSTRACT
Methyl Farnesoate (MF) was incubated with Y-organs from female Dungeness crabs(Cancer magister) from Southeast Alaska. These females are in the uppermost limits of the species' population range and exhibit temporally separated molting and ovarian maturation unlike those living in the lower ranges which couple these processes.  The purpose of this study was to determine the effects that MF would have on y-organ ecdysteroid (molting hormone) secretion from crabs in reproductive and non-reproductive stages. Reproductive staged females were classified by orange colored ovaries, in contrast to the white color seen in non-reproductive females.  Ecdysteroid levels from culture and hemolymph samples were analyzed using an enzyme linked immunosorbent assay (ELISA).  We found that no significant difference in ecdysteroid secretion between the control and MF treated groups.  Significant differences in ecdysteroid secretion were observed between the two control groups, reproductive and non-reproductive.  This may imply that y-organs could be responding differently to neuroendocrine hormones based on reproductive state.   This study can serve as a pilot study for future work investigating the effects of neuroendocrine hormones on female y-organs to gain more understanding of the factors controlling reproduction and molting.  In addition, this study shows that ecdysteroid levels found in hemolymph can serve as an indicator of which reproductive phase a female crab is in, providing a non-lethal method of analyzing populations of female Dungeness crabs.

BAT ABUNDACE AND PREY AVAILABILITY IN TIMBER HARVEST FORESTS OF SE ALASKA

Alan Hall, UAS REU Summer 2006 Student
REU Mentor: Dr. Matt Heavner, University of Alaska Southeast

ABSTRACT
Advances in bioacoustical monitoring techniques may allow estimations of population density and reveal other characteristics of bat populations. Previous research has shown bats in southeast Alaska may have been negatively affected by clear-cut logging practices. There is also an expressed need from bat researchers for an enhanced understanding of how prey availability affects habitat use. An attempt was made to elucidate the ecology of the insectivorous bats in Alaska through monitoring insect availability and correlating this to local bat abundance. Furthermore, this correlation was evaluated at study sites located in old growth and clear-cut sections of forest to reveal differences in habitat use.
The study was conducted at Prince of Wales Island in southeast Alaska. Eight total study sites, four in old growth and four in clear-cut, were chosen to account for variables of karst terrain, a bridge, and elevation (250 m), and two other sites with none of these variables were included for control. Bat population estimates were attempted using bioacoustical survey techniques involving a high frequency sound detector recording to a laptop computer. Insect availability was measured by using a black light trap.
Due to technical complications in determining bat abundance, final results are not available about the correlation between bats and insects in old growth and clear-cut forests. However, final data from the insect collector suggest that old growth forests have a higher availability of prey-sized insects.
For further research it is suggested that insect samples should be collected every hour to show peak times of insect availability so possible correlations can be drawn between bat presence and prey availability throughout the night.

The Influence of Changing Glacier Coverage on the Physical Hydrology and Hydrochemistry
of Coastal Watersheds in Southeastern Alaska

Logan Berner1, 2 and Eran Hood3

1 NSF, REU Student, Summer 2006, University of Alaska Southeast, Juneau
2 University of Alaska Southeast, Environmental Science Program, Juneau
3 REU Mentor, University of Alaska Southeast, Environmental Science Program, Juneau

ABSTRACT
Glaciers in southeastern Alaska are particularly sensitive to climate change because they have large areas of ice at low elevation. Currently, glaciers in this region are experiencing extremely high rates of ice loss as a result of rapid thinning and retreat. The purpose of this study is to examine how changes in glacial area are affecting the physical hydrology and hydrochemistry of coastal watersheds in and around the Juneau Icefield in southeastern Alaska. Our study area includes six adjacent watersheds that range in area from 30 km2 to 220 km2 and in glacier coverage from 0% to 59%. Three of our six study watersheds are continuously gaged by the U.S. Geological Survey. During the summer and fall of 2006, we sampled weekly for physical and hydrochemical parameters in all six watersheds. Physical measurements included: temperature, suspended sediment, and conductivity; and hydrochemical parameters included: total nitrogen, dissolved organic carbon, sulfate, and orthophosphate.
Glacial coverage exerted a strong influence on the physical characteristics of streamwater. Streamwater temperature and conductivity were negatively correlated with glacier coverage, while suspended sediment loads were positively correlated with glacial coverage. Glacial coverage also affected streamwater nutrient concentrations. For example, there was a significant negative correlation between glacier coverage and both total nitrogen and dissolved organic carbon concentrations. These results suggest that glacial recession within a watershed mediates a predictable transition from a cold, turbid, nutrient-poor stream to a warmer, clear-water stream that contains higher concentrations of carbon and nitrogen.
Percent glacial coverage also strongly explained watershed yields of water and nutrients. Area-weighted water yields decreased with decreasing glacier coverage. Additionally, the timing of water and nutrient fluxes varied among the watersheds, reflecting differences in the dominant controls on discharge. In heavily glaciated watersheds, discharge was strongly correlated with air temperature because streamflow is dominated by glacier melt. In watersheds with lower glacial coverage, discharge was more tightly tied to frontal precipitation events, resulting in water and nutrient fluxes being more pulsed rather than seasonal. Taken together, these findings suggest that the timing and magnitude of fresh water and nutrients delivered to near-shore marine systems will change substantially as glaciers continue to recede in coastal watersheds in southeastern Alaska.

Pilot Study of Pacific Sleeper Sharks (Somniosus pacificus) in Northern Southeastern Alaska

Steven Hsiao1,2, Suzie Teerlink1,3, and Elizabeth A. Mathews4

1 NSF, REU Students, Summer 2006, University of Alaska Southeast, Juneau
2 Mount San Antonio College, Walnut, CA
3 University of Alaska Southeast, Biology Program, Juneau, AK
4 REU Mentor, University of Alaska Southeast, Natural Sciences Dept., Juneau, AK

ABSTRACT
Pacific sleeper sharks (Somniosus pacificus) are most commonly known for scavenging on whale carcasses and more recently have also been documented to capture fast swimming prey such as salmon and squid. Since the early 1990s, there has been a decrease of more than 3,500 harbor seals (Phoca vitulina) (64-75%) in Glacier Bay National Park in southeastern Alaska (Mathews and Pendleton 2006). In the Gulf of Alaska, numbers of Pacific sleeper sharks increased between 1984 and 1996 (Mueter and Norcross 2002). Sleeper sharks (Somniosus spp.) have been documented to either actively prey on harbor seals or scavenge dead harbor seals. Increasing sleeper shark numbers and reports of seal remains in the stomachs of sleeper sharks caught as bycatch inspired us to investigate if sleeper sharks were playing a role in harbor seal declines. As a first step toward refining our research methods, we sampled sleeper sharks in Taku Inlet by longling. From the 450 hooks we set with an approximate soak time of 2 hours we captured 10 sleeper sharks. Samples from the sleeper sharks were archived for future analyses. Our necropsies of 6 of the captured sleeper sharks confirmed that sleeper sharks at this site were preying on salmon that were most likely alive when eaten. We found whole salmon and squid beaks inside the stomachs of several sleeper sharks. We did not find obvious remains of harbor seals in the stomachs of necropsied sharks, but the area we sampled was not near seal concentrations and such remains were not expected.

GROWTH AND DISTRIBUTION OF JUVENILE DUNGENESS CRAB, CANCER MAGISTER, NEAR JUNEAU, ALASKA

Matt S. Morris1,2, Mistee Vinzant3, Dani Morgan4, 5, and Ginny L. Eckert6

1 NSF, REU Student, Summer 2006, University of Alaska Southeast, Juneau
2 Oregon State University, Corvallis, Oregon
3 University of Alaska Southeast, Biology Program, Juneau
4 NSF, REU Student, Summer 2005, University of Alaska Southeast, Juneau
5 College of William and Mary, Williamsburg,
6 REU Mentor, University of Alaska Southeast, Natural Sciences Dept., Juneau, AK

Dungeness crab, Cancer magister, is a commercially important species ranging from California to Unalaska Island, and few studies have examined early life history stages in the northern range. In the summers of 2005 and 2006, we examined the density and distribution of juveniles and molts at intertidal beaches accessible by road in Juneau. Molts and/or live juveniles on beaches with suitable habitat were surveyed by visually scanning and/or raking the top 10 cm of substrate in a 50 m by 2 m transect at MLLW. Juvenile or molt carapace width (CW) and carapace length (CL) were measured to the nearest 0.1 mm. Density of molts and juveniles ranged from 0 to 7 per square m. Size frequency distributions indicate that settlement occurs in late summer/fall at approximately 7 mm CW, crabs molt a few times from September through May reaching 14 mm CW in May, 19 mm in June, and 25 mm in July. Growth of first-year Dungeness crab in Juneau resembles that in Puget Sound and is slower than growth in Grays Harbor or San Francisco Bay.

THE RELATIONSHIP BETWEEN WETLAND MICROHABITAT CHARACTERISTICS AND BOREAL TOAD BREEDING

Michel Ohmer1,2 and Sanjay Pyare3

1 REU Student, Summer 2006, University of Alaska Southeast, Juneau, AK
2 Biology Program, Cornell University, Ithaca, NY
3 REU Mentor, University of Alaska Southeast, Natural Sciences Dept., Juneau, AK

ABSTRACT
Current conservation efforts for the declining boreal toad (Bufo boreas) would be improved if breeding habitat needs were better understood. Therefore, as a part of a large-scale toad inventory and monitoring effort, we analyzed toad breeding occurrence with respect to 18 microhabitat characteristics. Data pertaining to both on-site (e.g. pH, water temperature, and percent emergent vegetation) and around-site (e.g. wetland area, elevation, and percent forested) variables were collected for 70 randomly selected high and low potential breeding sites at three geographic areas in Southeast Alaska in 2005 and 2006. After variables were screened to prevent model overfitting, multivariate logistic regression was performed to determine the group of characteristics that best distinguished breeding from non-breeding wetlands. We found that the combination of higher water temperature (p=0.004) and a lower percentage of shallow water in a wetland (p=0.002) had the most predictive power in determining toad breeding habitat. These results suggest that toads prefer the shallows of larger, deeper water bodies, as such wetlands potentially provide greater permanence, the option for predator escape, and deep areas of nighttime warm water refuge for tadpoles. There appears to be an important gradient of microhabitat variables for B. boreas wetland selectivity, and we recommend that these variables be considered when developing conservation initiatives concerning toad habitat protection in Southeast Alaska.

Breeding Site Fidelity and Philopatry in Ringed Seals (Phoca hispida)

Micaela Ponce, NSF, REU Student, Summer 2006, University of Alaska Southeast

REU Mentor: Dr. Brendan Kelly, Dean of Arts and Sciences, University of Alaska Southeast, Juneau

ABSTRACT
To predict the impacts that accelerated Arctic climate change will have on ice-inhabiting ringed seals, their population structure must be understood. Adult ringed seals demonstrate inter-annual fidelity to breeding sites; suggestive of philopatry. If ringed seals are philopatric, then what was once thought to be a few panmictic ringed seal populations may actually be comprised of many genetically isolated populations. In the 2005 and 2006 breeding seasons, 25 seals were tagged with a satellite transmitter. Of 13 seals tagged in Peard Bay, AK in 2005, four of them had satellite transmissions that carried over into the 2006 breeding season. Each of them returned to the same breeding site in 2006. The movement of three of these seals continues to be monitored as well as twelve additional seals tagged in 2006. Microsatellite and mitochondrial DNA markers are being analyzed from tissue samples that have been gathered in the field and from specimens at the University of Alaska Museum of the North. The combination of satellite tracking and genetic analysis will bring about a firm understanding of the population structure of ringed seals, which is essential in the planning of conservation and management of this subsistence species.

Landscape Connectivity Associated with Habitat Selection by Bufo boreas

Maria Santiago, University of Alaska Southeast, REU Summer 2006 Student;
Portland State University, Portland, Oregon

REU Mentor: Sanjay Pyare, University of Alaska Southeast, Juneau, Alaska

ABSTRACT
We studied landscape connectivity associated with the occurrence of the boreal toad, Bufo boreas, using information and data collected in 2005 and 2006 during an amphibian occurrence study in three different regions of southeast Alaska. B. boreas occurs in metapopulations defined as separate patches of populations that are ultimately linked by some level of migration or gene flow. Connectivity of patch wetlands may have a direct link to selection of habitat. A geographical information system (GIS) was used to estimate several different measures of connectivity within a 1.5km radius of 469 wetland patches. Measurements included structural, geographical, and functional aspects of connectivity and were estimated in terms of distance to other habitat, density of potential habitat, and migratory energy costs within a 1.5km radius of each potential habitat site. We found that 2 measures, mean Euclidean distance from utilized habitat to the nearest high potential habitat patch and the total energy cost to travel within a 1.5km radius of each site, were positively and significantly related to the presence of B. boreas. These findings support that certain aspects of landscape connectivity are important for habitat selection by Bufo boreas. More studies should be done to better understand the effects of habitat fragmentation and land use around wetland habitat.

The Effect of Mussel Density on the Survival of Nucella lima

Amber Stubler University of Alaska Southeast, REU Summer 2006 Student
SUNY Stony Brook, Stony Brook, NY

REU Mentor: David Tallmon, University of Alaska Southeast, Juneau, AK

ABSTRACT
During the late 1980's, Auke Bay, AK experienced a local extinction of a predatory gastropod, Nucella lima, due to tributlytin-induced imposex. Since then N. lima has begun to recolonize areas of the bay, however other areas remain unpopulated. I examined the interactions between the mussels (Mytilus edulis) and N. lima to determine whether the density of mussels in any given area affects the survival of recolonizing N. lima. Nucella lima preys on mussels and barnacles and therefore lives in areas of the intertidal zone dominated by these prey items. The mussels use their byssal threads as a predatory defense mechanism in order to capture N. lima and prevent being preyed upon. Using the program MARK, I looked at the difference in survival rates of N.lima in areas of low mussel density and areas of high mussel density. The results show that there is not a significant difference in survival between the varying mussel densities. This implies that although the mussels' defenses are successful sometimes, they do not have an adverse effect on the overall survival of N. lima. Other factors affecting recolonization should be investigated for more clues why N. lima is not successfully moving into areas it once populated.

PACIFIC SLEEPER SHARK: A POTENTIAL PREDATOR OR SCAVENGER OF HARBOR SEALS

Suzie Teerlink1, 2, Steven Hsiao1,3, and Elizabeth A. Mathews4

1 REU Student, Summer 2006, University of Alaska Southeast, Juneau, AK
2 University of Alaska Southeast, Biology Program, Juneau, AK
3 Mount San Antonio College, Walnut, CA
4 REU Mentor, University of Alaska Southeast, Natural Sciences Dept., Juneau, AK

ABSTRACT
In northern southeast Alaska, harbor seal (Phoca vitulina) numbers have declined, in some areas by more than 65%. The cause of this decline is unknown, although one hypothesis is that Pacific sleeper sharks (Somniosus pacificus) may be preying on or in competition for food with declining seal populations. The goal of this project was to better understand sleeper shark distribution relative to harbor seal pupping areas and to assess the possibility that sleeper sharks may be preying on harbor seals. The study region was focused on Yakutat, Alaska, a community near a tidewater glacial fjord where seal declines have been reported. Because sleeper sharks are commonly caught as bycatch on longline commercial fishing gear, we created a standardized and structured survey and interviewed 14 fishermen from Yakutat. The intention of this survey was to gather perceived sleeper shark distribution and concentrations relative to fishing efforts. Also, we worked as crew on a commercial halibut longlining expedition to; 1) to gain direct experience with sleeper sharks, 2) collect stomach contents and tissue samples, 3) to improve our interviewing skills through a hands-on fishing experience. From the 430 hooks set while fishing, 10 sleeper sharks were caught as bycatch, 6 of which were necropsied. No obvious seal remains were found in the shark stomachs; however, we were not fishing near known harbor seal concentrations. Fishermen in Yakutat reported the highest concentration of sleeper shark bycatch near the tidewater glacial fjord used by ~1,000 breeding harbor seals. This suggests a correlation between the distribution of sharks and harbor seals. Furthermore, 3 of the fishermen interviewed had cut open sleeper shark stomachs, 2 of which reported finding harbor seal remains indicating that sleeper sharks either preyed on or scavenged harbor seals. A proposal for a direct test of the predation hypothesis has been submitted for work in summer 2007.

 A Mark and Recapture Study Investigating Nucella lima Recolonization and Survival
after a Local Extinction

Sarah Wood1, 2 and David Tallmon3

1 REU Student, Summer 2006, University of Alaska Southeast, Juneau, AK
2 Humboldt State University, Department of Biological Sciences, Arcata, CA 95521
3 REU Mentor, University of Alaska Southeast, Natural Sciences Dept., Juneau, AK

ABSTRACT
Nucella lima, an intertidal snail, went locally extinct in Auke Bay Marina, Alaska, due to imposex (female genitalia modified to the point of dysfunction) caused by Tri-bulty-tin (TBT) in antifouling paints used on boat hulls. TBT contamination in the intertidal zone of the marina was found to be higher than in peripheral areas. Antifouling paints have been banned, and TBT levels are now extremely low in most of Auke Bay. However, snails have failed to recolonize much of their former habitat around Auke Bay Marina. We assessed factors limiting re-colonization success of N. lima by monitoring movement and survival using mark-recapture. Snails were captured and then separated into two groups. One group was relocated to Auke Bay Marina and the other group was returned to the collection (control) site. A suite of Cormack-Jolly-Seber models was used to estimate parameters of survival and capture probability. Microhabitat had a much greater impact on survival than release site, as survival did not differ between the formerly TBT-impacted marina and the control site. The results suggest that snails could persist in Auke Bay Marina if immigration increases or translocations are employed.

Predicting Suitability of Trees for Nesting by Marbled Murrelets in Southeast Alaska

Oscar Villafane1, 2 and Matt Kirchhoff 3

1 University of Alaska Southeast, REU Summer 2006 Student and
2 Florida State University, Tallahassee, Florida
3 REU MentorAlaska Department of Fish and Game, Juneau, Alaska

ABSTRACT
I measured a variety of characteristics of coniferous trees at three sites in southeastern Alaska to determine the relationship between these variables and the abundance of suitable nest platforms for Marbled Murrelets (Brachyramphus marmoratus)-a seabird that occurs along the coast of the Pacific Northwest and southern Alaska. To compute an index of suitable nest platforms, I took a digital photograph of each tree, counted the number of pixels representing the visible moss platforms, and converted those pixel counts to biomass. Only those platforms found within the canopy in the top half of the tree were considered suitable for Marbled Murrelet nests (Hamer and Nelson 1995*). Other variables measured include tree species, tree height, trunk diameter at breast height (dbh), stand basal area, proportion of live crown ratio, and tree age. Linear regression analyses show that tree height and trunk diameter are positively related to biomass of suitable moss platforms (N = 39 trees, P < 0.05). Old-growth trees (> 150 years) had significantly more suitable moss biomass than younger trees (P < 0.02). Tree species, stand basal area, and crown ratio were not significantly correlated with suitable moss biomass. My findings in this study are consistent with Marbled Murrelet studies in the Pacific Northwest and Canada that show preferential use of older, taller, larger diameter trees for nesting (Hamer and Nelson 1995). Marbled Murrelets are listed as a threatened species in California, Oregon, Washington, and British Columbia, with population declines linked to declining old-growth forest habitat. In Alaska, efforts to conserve remaining stands of older, larger-sized trees should benefit nesting Marbled Murrelets.
* Hamer, Thomas E., and Kim Nelson. USDA Forest Service. Characteristics of Marbled Murrelet Nest Trees. 1995. <http://www.fs.fed.us/psw/publications/documents/gtr-152/chap6.pdf>.

FORAGING PATTERNS OF BATS IN SOUTHEAST ALASKA

Mallott, Elizabeth K.1, and Matt Heavner2

1. University of Alaska Southeast, NSF, REU Summer 2005 Student;
Department of Biology, Grinnell College
2. REU student mentor, Department of Natural Sciences, University of Alaska Southeast

ABSTRACT
Five species of bats are found in Southeast Alaska (Parker, 1996). However, little is known about these populations and bioacoustics may be an effective way to learn more. We used acoustics to study the nightly activity of bats at two riparian areas (Turn Creek and Thorne River) on Prince of Wales Island, Alaska by leaving an Anabat II detector overnight. Three nights of recordings for each site were analyzed for presence of bats, activity patterns, foraging activity and total activity, using the number of pulses per ten minute period as a measurement of activity. We were not able to distinguish bat passes from each other because of the high density of pulses in the recordings. This suggests an uncommonly large number of bats at these two study sites. No discernable nightly activity pattern was found at either site, however there were differences in activity patterns between sites. The recordings at Turn Creek showed greater concentrations of activity, however recordings at Thorne River showed a higher mean level of activity. We found no significant differences in foraging activity or total activity between the two sites. A long term study is needed to address nightly activity patterns as the shortened periods of darkness in Alaska may be causing variations in behavior between Alaskan bat populations and bat populations in the rest of North America.

DOES SIZE MATTER?

Laurinda Marcello1, Dr. Nicola Hillgruber2 and Carl Reese2

1 2005 NSF, REU Student, Summer 2005, University of Alaska Southeast;
Lewis and Clark College
2 University of Alaska Fairbanks, School of Fisheries & Ocean Sciences

ABSTRACT
In recent years, the Alaska Department of Fish and Game (ADF&G) has noted a decline in the average daily commercial catch of fall-run chum salmon in the Taku Inlet, near Juneau, Alaska. This decline coincides with an increased number of juvenile chum salmon released the nearby Douglas Island Pink and Chum hatchery (DIPAC). The reason for this decline is unclear as there have been no industrial changes to the Taku River, nor have similar population changes occurred in other areas of Southeast Alaska. Since hatchery salmon juveniles are larger than their wild counterparts upon release, it is possible that feeding competition between the two groups may contribute to the decline. Our study examined whether sized-based feeding competition among juvenile chum salmon occurs. This initial pilot study was conducted solely with hatchery fish of different sizes. We conducted experiments in a flow-through tank at DIPAC. We varied both fish density (low density - LD, high density - HD) and food amount (low food - LF, high food - HF), resulting in four treatment types (LD/LF, LD/HF, HD/LF, HD/HF), each with four replicates. For each fish, we measured fork length (FL), weighed stomach content mass, and recorded the number of prey items eaten. For the data analysis, we divided the fish into two size classes: $<$ 54mm and $>$=55mm in FL. Our results indicate that juvenile chum salmon were food limited in the low food treatments. Large fish ate more prey items in high fish density situations than in low fish density situations, possibly suggesting that schooling may aid foraging success in large fish. Importantly, large fish ate more food by mass than did small fish. Small fish also tended to eat the least food in high density, low food conditions. In summary, the results of this pilot study indicated a potential for size-based feeding competition between chum salmon juveniles in the wild. In addition, we recommend a follow up study further examining feeding competition between chum salmon juveniles of both hatchery and wild origin.

INFERENCES FROM FISH-HOLDING BEHAVIOR OF MARBLED MURRELETS IN SOUTHEAST ALASKA

Christopher Millow, NSF, REU Student, Summer 2005, University of Alaska Southeast;
University of Delaware, Newark, DE

REU Mentor: Matt Kirchhoff, Alaska Department of Fish and Game, Juneau, AK

ABSTRACT
The Marbled Murrelet (Brachyramphus marmoratus) is a seabird that nests in coastal old-growth forests from northern California to Alaska. They forage on small schooling fish and can be seen on the water holding fish in their bills, presumably awaiting optimal conditions to deliver the prey to their nestling. During July 2005, I studied fish-holding behavior of the Marbled Murrelet in Port Snettisham near Juneau, Alaska to determine how it related to breeding status, nesting chronology, and marine habitat use. I conducted 65 focal area scans and recorded the fish-holding status and abundance of birds relative to time of day and period of summer (N = 11,991 birds counted). After a focal area scan, I selected random fish-holding birds (N = 84), and observed them until they consumed the fish, left the area, or were lost from view. Bird abundance was highest (P < 0.05) in late morning and during mid-July. The proportion of birds holding fish was highest (P < 0.05) in evening, and fish-holding behavior peaked in late July as the hatching cycle progressed. Of birds holding fish, 28% left with the fish (likely to a nest), 21% ate the fish, and 51% were lost from view with the final outcome of the fish undetermined. The proportion of birds leaving with fish was highest in early morning, while the proportion of birds consuming fish was highest in late morning. I found large concentrations of murrelets foraging in Port Snettisham, with high proportions of those birds catching and holding fish. These data indicate large numbers of birds are being drawn in from outlying areas. By tracking the Marbled Murrelet's abundance and fish-holding behavior, one can make inferences about proportions of breeders within the population, peak timing of egg hatch, and proportions of local versus distant nesters.

METHODS OF SAMPLING JUVENILE DUNGENESS CRABS IN SE ALASKA

Dani Morgan, NSF, REU Student, Summer 2005, University of Alaska Southeast;

REU Mentor: Dr. Ginny Eckert, University of Alaska Southeast, Juneau, AK

ABSTRACT
Dungeness crabs, Cancer magister, are a commercially important species in Southeast Alaska. They exhibit a complex life cycle, though little is known of the specific characteristics of their growth in Alaskan waters. In this study, I compared different methods for collection of Dungeness crabs during their juvenile stage. Two methods were used, settlement bags and pitfall traps. Settlement bags consist of multiple layers of fine plastic mesh inside a bag of looser mesh, to mimic suitable habitat for the settlement of megalopal and early juvenile crabs and are commonly used in juvenile crab research. Pitfall traps are buckets buried in the substrate, which the juveniles fall into and are unable to remove themselves. Both methods were set up along a 100 meter transect at each of two sites north of Juneau. I visited one field site daily during negative tides, and sampled all pitfall traps and settlement bags for juvenile crabs. I found that pitfall traps collected larger numbers of crabs overall, and was the only method tested that was able to collect J5-J10 older juvenile crabs. The settlement bags were more efficient than the pitfall traps for J1-J2 early stage crabs, however. The results of this project will make it easier for future researchers to find the correct method for a particular project. I also worked on making improvements to the settlement bag itself. I devised a system for retrieving the settlement bag through the water column without losing its contents, allowing sampling to occur at times other than extreme low tides and possibly in a wider range of habitats. I also tried using different sizes of outer mesh on the bags, though this did not result in an increase in either the number or the growth stage of crabs captured

ENVIRONMENTAL INFLUENCES ON HARBOR PORPOISE DISTRIBUTION IN AUKE BAY, ALASKA

Jennifer Saulus1 and Elizabeth A. Mathews2

1 NSF, REU Student, Summer 2005, University of Alaska Southeast;
University of Alaska Southeast, Juneau, AK

2 REU Mentor, University of Alaska Southeast, Juneau, AK

ABSTRACT
The harbor porpoise inhabits sub-polar and cool temperate coastal waters of the Northern Hemisphere. Although the species is well-studied in the Atlantic Ocean, information on harbor porpoise distribution and behavior in Alaska is very limited. We investigated the use of nearshore habitat by conducting shore-based visual surveys of porpoises in Auke Recreation Cove, a subsection of Auke Bay near Juneau where previous surveys had indicated periodically high numbers of porpoises. We surveyed the study area by systematically conducting two-minute scans of 4-6 degree wide sectors with binoculars equipped with an internal compass and reticles; surveys took from 31-68 minutes. We examined the effects of tide, time of day, presence of a calf, and geographic location on porpoise distribution and experimented with the efficiency of the established survey method. Data on harbor porpoise group size, travel direction and behavior (e.g., travelling, milling, or leaping) as well as vessel type, route and travel behavior through the study area were also collected for future analysis. We compared a two-minute scan per sector (Taylor and Dawson, 1984) to a 1.5 minute scan and found that the longer interval detected significantly more porpoises (mean=3.4 vs. 1.8, n=8). In 2000 and 2005, the mean number of porpoises per session was higher in June (n=61) compared to July (n=89) (4.5 vs. 0.96, p<0.0001). During June-July 2005 (n=61 surveys), the number of porpoises observed did not vary with tidal cycle, nor during four, 3-hr blocks from 07:00 to 19:00, although there was a tendency for lower numbers later in the day. Porpoises occurred significantly more in sectors near the eastern boarder of the study area, and this is also where we observed the majority of calves. Characterizing prey distribution, bathymetry, and currents in these areas may illuminate reasons for seasonally high porpoise densities in Auke Bay.

DIVING BEHAVIOR OF MARBLED MURRELETS AND PIGEON GUILLEMOTS IN SOUTHEAST ALASKA

Rebecca Walling, NSF, REU Student, Summer 2005, University of Alaska Southeast;
Carleton College, Northfield, MN

REU Mentor: Matthew Kirchhoff, Alaska Department of Fish and Game, Juneau, AK

ABSTRACT
Marbled Murrelets (Brachyramphus marmoratus) and Pigeon Guillemots (Cepphus columba) are diving seabirds found in Southeast Alaska. Marbled Murrelets forage primarily on schooling fish found throughout the water column whereas Pigeon Guillemots forage primarily on solitary fish near the bottom. Because Marbled Murrelets feed on less predictable prey, I hypothesized that their underwater times would be more variable than those of Pigeon Guillemots and uncorrelated with depth. I was also interested in whether the birds' surface time between dives was more controlled by recovering from the previous dive or anticipating the next dive. During July and August 2005, I recorded underwater and intervening surface times for Marbled Murrelets and Pigeon Guillemots in Port Snettisham. At Port Amner, Pigeon Guillemots foraged in water 4-8 meters deep. At Sentinal Point, both Marbled Murrelets and Pigeon Guillemots foraged in water 14-24 meters deep. Observations were shore-based. Marbled Murrelet dive data from the previous summer (Point Bishop, water depth: 10 meters; Pontius, unpublished data) was used for further comparison. Pigeon Guillemots foraging at Sentinal Point had significantly (P<0.01) longer dive times (x=73.4s, N=53) than those foraging at shallower Point Amner (x=41.6s, N=87). As predicted, Marbled Murrelet dive times did not differ significantly (P<0.01) between sites. At Sentinal Point, where both species foraged, Marbled Murrelet dive times were more variable (CV=0.263) than those of Pigeon Guillemots (CV=0.162). A stronger correlation between the surface time and subsequent dive time (Marbled Murrelet=0.307, Pigeon Guillemot=0.602) indicates that these birds may be able to anticipate the oxygen needed to make their next dive successful.

IMPOSEX AND SURVIVAL OF AN INTERTIDAL SNAIL IN AUKE BAY, ALASKA

Teagan Ward, NSF, REU Student, University of Alaska Southeast, Juneau, AK Summer 2005;
Biology Department, Carleton College, Northfield, Minnesota.

REU Mentor: Dr. David Tallmon, UAS, Juneau, Alaska

ABSTRACT
Exposure of female Nucella lima to low concentrations of tributyltin (TBT) results in the development of imposex (the superimposition of male reproductive characteristics onto female snails). In a population affected by imposex, population expansion may be limited by reproductive stress as well as the survival of adults within a population. Variations in reproduction and survival of N. lima populations were studied at sites of varying distance from Auke Bay Harbor. Fifty snails were collected from eight sites around Auke Bay. Sex was determined and penis sizes were measured. Relative penis size (RPS) indices were calculated for all sites. Capture-mark-recapture (CMR) techniques were used to estimate survival probabilities at three sites in Auke Bay. There was evidence of variation in survival estimates between populations in the Auke Bay area. Lowest survival was estimated at sites closest to the affected TBT area near the Ferry Terminal site. Variation in the frequency of imposex females and RPS of imposex females was found in populations at different sites. The highest RPS indices were found at sites at and near the Ferry Terminal; however, there still appears to be evidence of recruitment in these areas. Survival and imposex both appear to be affecting the expansion of N. lima populations in the Auke Bay area.

THE ROLE OF PREDATION ON THE FECUNDITY OF TWO SUBTIDAL SNAILS WITH DIFFERING REPRODUCTIVE STRATEGIES

Kristina Sawyer, University of Alaska Southeast,
REU Summer 2005 Student Illinois Wesleyan University, Bloomington, IL

REU Mentor: Christopher Siddon, Ph.D, Research Associate Univeristy of Alaska Fairbanks School of Fisheries and Ocean Sciences, Juneau, AK

There is a great deal of diversity among reproductive strategies even among closely related organisms. Within the Class Gastropoda there are a variety of methods including broadcast spawning, release of planktonic or veliger larvae, and encapsulation of eggs. By comparing two similar subtidal snails, I was able to analyze the success of their two different reproductive strategies to a variety of potential predators. Fusitriton oregonensis lays a flat round egg mass that it then guards against potential predators for 7-8 weeks until the eggs hatch as planktonic veliger larvae. Neptunea lyrata, however, lays a tall cylindrical egg mass that it does not guard and the eggs will hatch in 8-12 months as crawl away larvae. The numbers of larvae released varies significantly between the two snails with around 900,000 larvae emerging from a single Fusitriton oregonensis egg mass and approximately 90 from a Neptunea lyrata egg mass. I tested the effects of predation by urchins (Strongylocentrotus droebachiensis), and two seastar species (Evasterias trochelii and Pycnopodia helianthoides) on these two different egg cases. I experimentally removed half of the adult snails from the F. oregonensis egg cases and exposed the unprotected egg masses to the predators. I found that none of the predators consumed any of the guarded egg cases. The urchins, however, had a significant impact on the unguarded egg cases. I calculated this effect to be a loss of 32 +/- 10.6 egg capsules per urchin in 24 hours. This amounted to a loss of around 125,000 eggs and a 14% decrease in the overall fecundity of the snail in just 24 hours. I performed the same experiment with the naturally unguarded N. lyrata egg cases. None of the predators consumed any of the egg cases in this experiment. Clearly, the guarding behavior of Fusitriton oregonensis is an important aspect of their reproductive method, whereas the Neptunea lyrata egg cases are effectively protected by other methods.

TEMPORAL AND WEATHER INFLUENCES ON HAUL-OUT BEHAVIOR OF RINGED SEALS, PHOCA HISPIDA

Waterhouse, Lynn1, Kelly, Brendan P.2

1 NSF, REU Student, Summer 2005, University of Alaska Southeast; University of Dayton, Dayton, OH

2 REU Student Mentor, Dean of Arts and Sciences and Associate Professor of Marine Biology, University of Alaska Southeast

ABSTRACT
In winter and early spring, ringed Seals (Phoca hispida) rest on the ice surface in snow caves (subnivean lairs). In late spring, they emerge from the lairs and rest in the open. Ringed seals can be counted during aerial surveys only after they have emerged from those lairs. We investigated the relationship between resting bouts on the ice and temporal and weather variables. From 1999 to 2003, sixty-six ringed seals were captured and tagged in Prudhoe Bay, Alaska. A VHF transmitter was attached to the back and/or hind flippers of each seal and time out of the water was recorded. Time and weather variables including air temperature, snow temperature, wind speed, wind direction, wind gust, wind gust direction, barometric pressure, percentage cloud cover, presence of fog, dew point, and relative humidity were recorded hourly. Univariate analysis showed no correlation between any of the factors and haul-out bout duration or actual occurrence. No correlations were found using multivariate analyses. The frequency of resting bouts in lairs for less than one hour was disproportionately high among females.

AT-SEA SURVEYS OF MARBLED MURRELETS: METHODOLOGICAL CONSIDERATIONS

Jennifer L. Carroll, UAS REU Summer 2004 Student
REU Mentor: Matt Kirchoff, Alaska Department of Fish and Game

ABSTRACT
Marbled murrelets (Brachyramphus marmoratus) are solitary nesters, and nest in the tops of old-growth trees. As a result, surveys are necessarily conducted on populations at sea. We evaluated the accuracy of alternative line transect methods, and described the spatial distribution and density of marbled murrelets in Stephen's Passage, Southeast Alaska. We used these results to develop an optimal survey design. We found that the perpendicular distance from the object to the transect centerline could be more accurately calculated by estimating radial distance and angle, than by estimating the perpendicular distance directly. Repeated boat surveys along 23 transects (range 5.4 - 12 km) were conducted in the study area using GPS to record all bird locations spatially. The information gathered from the survey produced density estimates of 41.3 murrelets/sq. km (95% CI =25.73 to 50.268) for June and 47.1 murrelets/sq. km (95% CI = 30.546 to 55.707) for July. Half of all murrelets occurred within 2.0 km of the shore, and peak density occurred 1.7 km from shore. Bird density varies greatly with distance from shore, therefore, the optimal survey design would orient transects perpendicular to shore and calculate density from line transects using radial distance estimates and measured angles.

SPECTROGRAPHIC ANALYSIS OF RECORDED BAT ECHOLOCATION CALLS FOR THE DEVELOPMENT OF A ROBUST BAT MONITORING SYSTEM IN SOUTHEAST ALASKA

Michael Glista, UAS REU Summer 2004 Student
REU Mentor: Dr. Matt Heavner, University of Alaska Southeast

ABSTRACT
The most recent and extensive effort to document the occurrence of bats in Alaska confirms that five species inhabit certain parts of the state for at least a portion of the year. However, much remains uncertain about the geographic range, seasonal distribution, and population size and dynamics of these northern bats. This project aims to clarify these uncertainties by building upon that which is already known about bats in Southeast Alaska. Within the next two years, the investigators will develop a robust, sophisticated bat sensor system capable of monitoring bat activity for extended periods of time. This bat detector array will employ a software program capable of automatically identifying bat calls. For this component of the study, in addition to the development of the bat detector system, bat calls recorded in Southeast Alaska by D. Parker et al. (1997) have been analyzed in order to determine what sounds are likely to be recorded during the bioacoustical monitoring of the region. In particular, the sounds on the tapes were investigated and classified, the different types of identified signals were processed and described, and a preliminary investigation of the parameters that can be used to identify different species of bats in Southeast Alaska by their echolocation calls was conducted. Two factors, duration and frequency of maximum power, were found to be useful in discriminating between sound types. Although measurement and consideration of these factors alone theoretically make automated call identification possible, further statistical analysis may be necessary to ensure more accurate sorting.

NEAR SHORE FORAGING BEHAVIOR OF MARBLED MURRELETS IN STEPHEN'S PASSAGE

Kira Pontius, UAS REU Summer 2004 Student
REU Mentor: Matt Kirchoff, Alaska Department of Fish and Game

ABSTRACT
The marbled murrelet is an alcid that nests in old growth forests and lives and forages at sea. I studied near shore diving behavior of marbled murrelets (Brachyramphus Marmoratus) in mid July, at Pont Bishop near Juneau Alaska. Birds were observed from land during all stages of tide and over all daylight hours on 3 days in mid July. I recorded 1964 behavioral observations on 177 birds, including 887 diving bouts. The mean dive time was 27.1s, sd=10.1s, and the mean surface time was 10.5s, sd= 8.4s. I found as tidal stage increased from low to high tide both surface and underwater time increased significantly (P < 0.05). Birds foraging in pairs spent more time under water (mean 31.1 s) compared with singles (mean = 26.1 s). Pairs also spent more time recovering on the surface in between dives than singles (14.4 s versus 9.7 s). All differences in up times and dive times were significant (P< 0.05). Average group size increased with increasing tides p=0.000. I also found birds that performed a pre-dive head dip spent significantly more time underwater (30.8 s) than birds that dove without a head dip (26.0s) (P= 0.00).

DECAPOD LARVAE HITCHHIKING ON CNIDARIANS IN GLACIER BAY

Cirse Gonzalez, UAS, REU Summer 2004 Student
REU Mentor: Dr. Ginny Eckert, University of Alaska Southeast

ABSTRACT
Interactions between planktonic crustacea and gelatinous zooplankton have long been noted by scientists. This study examined the association between the cnidarians Aurelia aurita and Cyanea capillata and decapod larvae in Glacier Bay National Park, Alaska. At eight, random locations in the east arm and lower bay, decapod larval abundance was surveyed both from jellyfish collected in horizontal trawls and vertical zooplankton tows. Decapod larvae from both samples were identified to species and stage. Both Chinoecetes tanneri and Cancer magister were found in greater numbers on the jellyfish than in the water column. Implications of this interaction could affect distribution of these commercially fished species. Consideration of this interaction is recommended for any future study surveying decapod larvae.

INFLUENCE OF PREDATION RISK ON THE MOVEMENT OF THE SUBTIDAL WHELK, NEPTUNIA LYRATA

Alison Gould, UAS REU Summer 2004 Student
REU Mentor: Dr. Chris Siddon

ABSTRACT
Movement is ecologically important in maintaining an organism's population, although often difficult to measure, especially for far ranging species. In such cases, model systems become a useful means for simplifying these larger, more complicated systems. We examined the Lyre Whelk (Neptunea lyrata) as a potential model system for studying movement. We first quantified the density, and the size frequency distribution (measured in shell length) of a subtidal population of N. lyrata along the northeastern coast of Admiralty Island in southeast Alaska. Whelk density at depths of 7, 10, 13, 15, and 20 meters were 0.3 + 0.5, 4.4 + 4.4, 3.2 + 3.1, 5.3 + 5.1, and 3.2 + 3.0 N. lyrata respectively (#/40 m2 + SD), and the average shell length was 99 mm, ranging between 60 and 140 mm. The effects of shell length and predation by the sea star, Pycnopodia helianthiodes on the movement of N. lyrata were studied in a series of individual mark and recapture (IMR) experiments in which tagged snails representing a range in shell length were placed into circular plots (20 meters in radius) both with and without the presence of predators. Individual moves were measured as a random walk over 6 hours (at 2 hour intervals) and the net squared displacement (D) was calculated for each N. lyrata. Trial one showed a significant relationship between the size of the snail and their displacement, in which smaller snails moved less than larger ones. In both trails two and three however, the size of the snails had no significant effect on their displacement; therefore, in combining the data from these trials there was a significant effect of the presence of predators, in which snails in the predator and non-predator treatments had average net squared displacements of 0.55 + 0.05 and 0.27 + 0.06, respectively (D + SE). These results support the hypothesis that both size and predation will effect the movement of N. lyrata.

KELP BEDS AS HABITAT AND NUTRIENTS FOR INVERTEBRATES IN SOUTHEAST ALASKA

Douglas Rasher1, Elizabeth Calvert2, and Michael Stekoll3

1 UAS, REU Summer 2004 Student, Lyman Briggs School, Michigan State University
2 Juneau Center School of Fisheries and Ocean Sciences, University of Alaska Fairbanks,
3 REU Mentor: Department of Natural Sciences, University of Alaska Southeast.

ABSTRACT
Kelp beds act as an important source of habitat for a variety of invertebrate species. In addition, certain algal species may be an essential source of food for invertebrates. To test the hypothesis that the presence of understory kelp species (Laminariales) alters invertebrate species abundances, a large scale manipulation study was conducted near Auke Bay, Alaska. In June 2004, study areas were selected and manipulations were performed in order to create two replicate kelp (600 m2) and control (600 m2) plots. In July and August 2004, visual quadrat surveys were performed to quantify, as well as algal composition and density at each site. Microinvertebrates were quantified using light traps deployed one meter from the surface and one meter from the substratum (surface and bottom locations), in both kelp and cleared sites, to test for the effects of location in the water column and presence of algal structure on microinvertebrate abundance. Visual quadrat data revealed that there were significantly greater abundances of combined shrimp species and Pycnopodia helianthoides in plots where understory kelps were present. In contrast, the abundance of combined snail species were greater in cleared plots. Light trap results indicated that species abundance of shrimps, cumaceans, amphipods, and snails were significantly greater in light traps located at the bottom of plots where understory kelps were present. These results indicate that the presence of understory kelps does alter invertebrate species abundance. The removal of these kelps may have profound effects on the ecological interactions present in kelp beds.

DETERMINING GROWTH POTENTIAL UTILIZING HORMONE LEVELS IN THE DEEP SEA CRAB, MACROREGONIA MACROCHIRA

Matt Richards1, Sherry Tamone2 and Thomas Shirley3

1 Department of Biology, Western Washington University, Bellingham, WA,
2 REU Mentor: Department of Biology, University of Alaska Southeast, Juneau, AK
3 School of Fisheries & Ocean Sciences University of Alaska Fairbanks

ABSTRACT
Macroregonia macrochira is a deep sea spider crab, which ranges from 900 to 3000 meters in depth. M. macrochira is a majid crab related to the commercially important Tanner and snow crabs. To gain a better understanding of the biology of deep-sea spider crab, morphometric measurements and hemolymph samples were required. The crabs were collected from depths of 900 to 3000 meters using crab traps. The traps were sent down in the Gulf of Alaska located over several seamounts. Measurements included shell length, width and chelae height. These measurements showed morphometrically mature males did not share the allometric growth changes associated with functional maturity as do the Tanner and snow crab. Functionally mature males had a longer chelae length compared to the immature male. The chelae length in mature males equaled the length of their first pair of walking appendages. 3ml of hemolymph was withdrawn from each crab. The hemolymph was analyzed by an enzyme-linked immunosorbent assay (ELISA). The ELISA specifically measured ecdysone (molting hormone) levels in order to determine growth potential. Elevated levels of ecdysteroid are good indicators of growth whereas low ecdyteroid levels can indicate a terminal molt. Ecdysone levels showed similar patterns compared to Tanner and snow crab. M. macrochira ecdysteroid levels were ten times higher in when compared to other majid crabs.

DETERMINING DIET AND FORAGING BEHAVIORS OF RINGED SEALS IN THE BEAUFORT SEA

Stephanie Sell, UAS REU Program Summer 2004
REU Mentor: Dr. Brendan Kelly, University of Alaska Southeast

ABSTRACT
We analyzed the feasibility of using an underwater camera system along with scat samples to determine the diet and foraging behavior of ringed seals under the shore-fast ice of the Beaufort Sea. In a pilot study, we attached an underwater digital video recorder (CRITTERCAM) to an adult female ringed seal. Scat samples were collected from that seal and two others. The camera recorded continuously for 2h directly after deployment. Underwater behaviors recorded by video were categorized and quantified. Distinguishable prey items in scat samples were identified to the lowest taxonomic level. Most (61%) of the seal's time was spent resting in one of approximately 9 breathing holes she used during the 2h recording period. The video record also included prey capture and other non-foraging behaviors. Prey identified in the scat samples mainly consisted of isopods (Saduria entomon, S.sabini), gammariid amphipods, and Arctic cod (Arctogadus glacialis). Underwater camera systems and scat analysis can extend our knowledge of ringed seal diet and foraging behaviors. We recommend programming the video recorder to sample for 12 minutes per hour (3min every 15min) and only when submerged below the ice to extend the record of foraging behavior.

HEAT SHOCK PROTEIN EXPRESSION IN ADULT ZEBRAFISH AFTER EXPOSURE TO OIL

Matthew Siegle, UAS REU Program Summer 2004
REU Mentor: Dr. Sherry Tamone, University of Alaska Southeast

ABSTRACT
Oil contains many different polycyclic aromatic hydrocarbons (PAHs), which are known to cause detrimental developmental abnormalities including cardiac dysfunction, edema, spinal curvature and reductions in craniofacial structures. In addition, PAHs have been shown to persist in near-shore sediment for a decade after an oil spill. This long-term exposure to sub-lethal PAH concentration influences population recruitment and multigenerational fitness, thus representing an important yet ambiguous part of the total impact of oil spills on biota. In environmental monitoring, the use of a biomarker is a very powerful tool. By using a physical, quantifiable characteristic of an organism, which is representative of physiological stress, one could look to that characteristic and, if physiological stress is observed, infer the existence of a harmful environmental "stressor". This study is aimed at characterizing hsp 70 (a heat shock protein known to be up regulated in vertebrate cells upon physiological perturbation) in zebrafish after they have been exposed to sub-lethal concentrations of crude oil. Hsp 70 concentration will be quantified in zebrafish gill and viscera tissues over a 32 h sampling period. Sampling will be done after 0, 1, 2, 4, 8, 16, and 32 h of exposure to the sub-lethal oil concentration. To date, I have been trouble shooting the western blot analysis (protein analysis technique). KODAK image analysis will be used to quantify hsp 70 concentrations in the respective tissues.

CIRCULATING ECDYSTEROIDS IN MATURE AND IMMATURE SNOW CRABS (CHIONOECETES OPILIO)

Timothy Baldwin, UAS, REU Summer Program 2003
North Carolina State University

ABSTRACT
Immature and mature male snow crabs were studied to compare the difference in circulating ecdysteroid concentrations (molting hormone). Crabs were collected from the Bering Sea and maintained at University of Alaska Southeast. Each crab's carapace width and cheliped height were measured and recorded. The crab was tagged and a hemolymph sample withdrawn then returned to its tank. Molt stage for juvenile male snow crabs were determined by setogenesis. The exopodite of the second maxilliped was removed and examined for cuticular changes. Ecdysteroid concentrations were measured using an established ELISA (Enzyme Linked Immunosorbent Assay. The sample was first extracted in 75% methanol, and then assayed using an Elisa to determine the molting hormone concentration. Molt stages were related to ecdysteroid concentration. It was found that the ecdysteroid concentration of immature males was significantly higher than that of mature snow crabs (p= 0.004). Ecdysteroid concentration in immature crabs was 5.74 ng/ml while the concentration in mature crabs was 1.85 ng/ml. All the juvenile crabs were found either to be in the premolt or intermolt stage. Ecdysteroid concentrations of premolt crab were not significantly different from ecdysteroid concentrations in the intermolt stage. Immature crabs were in the early part of the premolt molt stage, so that there is not a considerable difference in hormone levels between the two molt stages.

Predicting Lair Abandonment by Ringed Seals Based on Physical Properties of the Snowpack

J.E. Conway
Davidson College and UAS, REU Summer Program 2003

ABSTRACT
Poster Presented at the Institute of Arctic and Alpine Research (INSTAAR), 34th Annual International Arctic Workshop, Boulder Colorado, 11-13 March

Ringed seal (Phoca hispida) populations may be responding to habitat changes associated with industrial activity and climate change in the arctic. Population assessment, however, has relied on visual surveys of the extensive sea ice habitat, and interpretation of those surveys has proven difficult. Throughout most of the year, ringed seals are not visible because they are feeding underwater or resting in lairs excavated in the snow covering the ice. They are visible on the surface only in the window between the onset of snowmelt, when lairs are abandoned, in late spring and ice breakup in summer. Surveys are meant to take place during that window, but the relationship between the onset of snowmelt and the timing of lair abandonment is not well understood. We used radio-telemetry to determine when 16 seals abandoned their lairs and compared the timing of lair abandonment with changes in cold content of the local snowpack. Snowpack cold content is the amount of energy required to raise the average temperature of a snowpack to its melting point (0º C). Thus, cold content integrates average density, average temperature, and depth of the snowpack-all of which are directly related to the structural integrity of the snowpack. Our findings suggest that cold content is an accurate gauge of the structural integrity of ringed seal lairs. Cold content also was strongly correlated with snow temperature at the ice surface and that parameter may prove to be a more convenient predictor of lair abandonment. Predicting the timing of lair abandonment will allow for more accurate aerial surveys of ringed seal populations.

INFLUENCE OF PREDATION ON HABITAT SELECTION BY RINGED SEALS

Kyndall B.P. Hildebrandt and Brendan P. Kelly

ABSTRACT
Ringed seals create breathing holes each fall, when the ice begins to solidify, and maintain those holes through the winter by scratching at the ice with their claws. Where enough snow accumulates over a breathing hole, seals often excavate a snow cave above the hole. In the winter, seals rest and give birth on the ice, protected from the cold and predators by the snow cover. In the spring and early summer, seals resting on the ice are no longer under the protective snow cover. Basking in the sun allows seals to elevate their skin temperature and regenerate epidermal cells. Not being concealed under snow, however, makes them vulnerable to surface predators. Basking ringed seals alternate between lying flat and raising their heads to scan for predators. We hypothesized that ringed seals would select basking sites where snow depth does not inhibit their ability to see predators. We further hypothesized that breathing holes that had lairs associated with them would be surrounded by deeper snow and be less suitable for basking seals. From 1998 - 2003, dogs were used to locate lairs, breathing holes, and basking sites off the shore of Prudhoe Bay, Alaska. Snow depths at the seal holes were recorded using a snow probe. Snow depth remained constant over six years, and snow depth was deeper at lairs than at breathing holes. Seals basked at areas of lower snow depth and more often at breathing holes than at lairs. Thus, ringed seals selected basking sites that enhanced vigilance.

ARE DECLINES IN HARBOR SEAL NUMBERS NEAR SPIDER ISLAND IN GLACIER BAY RELATED TO HUMAN DISTURBANCE?

Kate Kanouse and Elizabeth A. Mathews

ABSTRACT
The number of harbor seals (Phoca vitulina) in Glacier Bay National Park have declined by 64-75% since 1992. Counts indicate that the population was relatively stable from 1992 to 1996 with declines most evident after 1996. In 11 of the summers from 1991 to 2003, counts and behavioral observations, including disturbances by potential marine mammal predators (killer whales and Steller sea lions) of harbor seals and by vessels (primarily kayakers) have been made near Spider Island, the largest terrestrial haulout in Glacier Bay. Two of several hypothesized causes of the declines are increased human disturbances and increased predation. We conducted an initial test of these hypotheses by comparing disturbance rates (number/observation hour) during the period of time before the decline (1991-1996) to those from after the decline became pronounced (1997-2003). We used Fisher's Exact tests to compare human-caused and predator-caused disturbances from the two time periods. Human disturbances were significantly lower in the 1997-2003 period compared to the earlier, non-decline period (16/83 hrs vs. 23/234 hrs; p = 0.3), suggesting that disturbances by humans are not a key factor in the declines at this site. In contrast, we found a non-significant increase (0/83 hrs vs. 7/234 hrs; p = 0.11) in disturbances by predators. Although the predator disturbance rate was not statistically significant, the increase may be biologically meaningful. We conclude that predation is a more likely factor than human disturbance in the decline in harbor seals, but further studies are needed to verify if predation may have increased mortality.

EFFECTS OF DENSITY ON MOVEMENT OF THE GIANT RED SEA CUCUMBER

Steve McMurray, UAS, REU Summer Program 2003
Hiram College

ABSTRACT
The Alaskan sea cucumber fishery was established in 1987 to meet an increased demand by Asian markets for the dried product beche-de-mer after the collapse of traditional Indo-Pacific fisheries. The target of this fishery, the giant red sea cucumber, Parastichopus californicus, is found off the west coast of North America from Baja California to the Gulf of Alaska. This fishery is currently managed via a surplus production model developed by the Alaskan Department of Fish and Game in 1990. However, managers have little information on the biology of P. californicus for making sound fishery decisions. Even basic knowledge about the movement patterns of this holothurian is lacking. This study determined how population density affects the rate of movement of P. californicus. In 10 x 10 m plots at two sites in Southeast Alaska, densities of P. californicus were manipulated by divers using SCUBA. Movement rates of P. californicus within these plots were then measured every twenty-four hours over the course of three, five day trials. We found no significant effect of density on movement rate. The limited results of this study indicate that cucumbers are not likely to migrate from more dense areas to less dense or cleared areas after fishing has occurred. Further studies are needed to provide information necessary to ensure a sustainable P. californicus fishery.

Bull Kelp, Nereocystis leutkeana, as recruitment habitat for juvenile fishes and invertebrates in southeast Alaska, determined by use of light traps

Erin Meyer, UAS, REU Summer Program 2003
Cook College, Rutgers

ABSTRACT
Canopy forming kelp, such as Macrocystis pyrifera and Nereocystis leutkeana, are becoming increasingly recognized as important habitat for both fishes and invertebrates. Off the coast of Juneau, Alaska, N. leutkeana is the dominating canopy forming kelp, and few studies have been conducted exploring its role as a habitat. This study used light traps to capture juvenile fishes and invertebrates from four sites within the Saginaw Channel. Two sites were cleared of N. leutkeana in order to isolate the role of canopy kelp from other biological factors, and two sites were unaltered. Two mooring lines were set up at each of the four sites, and two traps were attached to each of the mooring lines, one meter above the substrate and one meter below the surface. The light traps were deployed for 24 hours. A total of five trials were completed between July 8 and August 18, 2003. The mean invertebrate counts for the bottom light traps for the canopy present and canopy cleared sites are significantly different to one standard deviation. The mean invertebrate counts for the surface light traps for the canopy present and canopy cleared sites are not significantly different. The mean invertebrate counts for the bottom light traps were 100 times greater than for the surface light traps. No significant differences between the fish counts were found. Since only five trials were completed in this study, more trials and sampling methods need to be used in order to determine the importance of N. leutkeana as habitat for fishes and invertebrates.

PHYSICAL DISINTEGRATION OF FECAL PELLETS OF THE RED SEA CUCUMBER (PARASTICHOPUS CALIFORNICUS)AT DIFFERENT CURRENT VELOCITIES

Kevin Turner, UAS, REU Summer Program 2003

ABSTRACT
Fecal pellets of the giant red sea cucumber disintegrate rapidly under field conditions, but deteriorate more slowly when exposed to minimal or no current in laboratory conditions. Fecal pellets were monitored in the field at Amalga Harbor, and in lab in two different flow tanks set at a control speed of no current and at a "maximum" speed of 11.8 ± 0.7 (x ± s.d.) cm/sec, separately. Pellets in the control treatment first showed complete disintegration after 9 days, and several were still intact when the trial ended after 13 days. The max speed treatment had some pellets reaching complete disintegration beginning at 4 days, but the majority were still intact when the trial ended after 5 days. Pellets in the field completely disappeared after 2.4 ± 0.5 days (x ± s.d., n=7). Under the current forces experienced at Amalga Harbor, sea cucumber pellets are no longer visible after more than just a few days. However, at the presumably lower currents experienced in lab in the max and control treatments, disintegration is far slower.

The Effect of Tag Weight on Tanner Crab (Chionoecetes bairdi) Movement: Implications for Sonic Tagging Procedures

Lia Herron, Dr. S. James Taggart, Jennifer Mondragon

ABSTRACT
The USGS Glacier Bay Field Station is tracking sonic tagged Tanner crabs and red king crabs in the East Arm of Glacier Bay National Park. The goal of this research is to estimate the length of time breeding adults spend inside and outside of a marine reserve (transfer rate). Sonic tag weight is assumed to have an insignificant effect on crab movement, but this assumption has not been verified. If sonic tags reduce crab movement, transfer rate could be underestimated. Therefore, it is important to determine the effect of tag weight on crab movement. For this study, two G-Force loggers were used to record three-dimensional acceleration, due to gravity and movement, of adult male Tanner crabs. Lead weights were added to the loggers to simulate sonic tags of varying weights. Changes in crab movement between seven different tag weights (treatments zero through six) were then compared. The crab's movement in treatment one was similar to its movement in treatment zero-a neutrally buoyant logger used as the control-suggesting that treatment one had little effect on the crab. In contrast, when compared to treatment zero, treatment three and six reduced the crab's movement. These results demonstrated that heavy tags can affect Tanner crab movement. However, to determine the maximum weight a crab can carry without affecting its movement, treatments will need to be conducted on a finer scale.

Effects of Eyestalk Ablation on Ecdysteroid Levels of the Snow Crab, Chionoecetes opilio:
Indications for a Terminal Molt

Melissa Adams. 2002

ABSTRACT
Molting enables decapod crustaceans to confront the problem of growth within the confinement of an exoskeleton. Modes of hormonal regulation exhibit control of this process. Bilateral eyestalk-ablation of crustaceans results in the removal of the sinus gland, an endocrine gland responsible for the secretion of Molt Inhibiting Hormone (MIH). MIH inhibits the secretion of the molting hormones (ecdysteroids) and therefore the procedure of eyestalk -ablation, serves as a prime model for investigating crustacean endocrinology in a controlled laboratory setting. Crabs of the family Majidae are believed to undergo a terminal molt, after which they are no longer able to grow. Snow crabs belong to this family, yet it is unclear as to whether males actually undergo the terminal molt. The goal of this project is to quantify levels of circulating ecdysteroids in female snow crabs Chionoecetes opilio before and after eyestalk-ablation. Female snow crabs undergo a terminal molt as a function of reproductive maturity and will serve as a comparison for mature and juvenile male C.opilio. This is an important area of research in crustacean endocrinology not only due to a lack of knowledge of the molt cycle of Chionoecetes but also due to the commercial importance of snow crabs.

 
DISTRIBUTION AND RELATIVE ABUNDANCE OF LARVAL CRABS IN GLACIER BAY

Jeff Douglas, Ginny Eckert, James Taggart, Jennifer Mondragon, Gail Irvine. 2002.

Poster presentation: Aquatic Sciences Meeting. American Society of Limnology and Oceanography (ASLO). Salt Lake City, Utah. Feb. 8-14, 2003.

ABSTRACT
Glacier Bay National Park in southeast Alaska supported a commercial fishery for Dungeness crab, Cancer magister, until 1999. The recent fishery closure makes it a unique place to study the recovering crab population and test theories about marine reserves. The bay is a large (1,255 km2) recently deglaciated fjord estuarine system with many tidewater glaciers. Dungeness crabs have a complex life history that includes a planktonic larval stage. It is unknown whether crab larvae released in Glacier Bay are exported or retained within the reserve. We hypothesized that Dungeness crab larvae would not be found in the upper arms or the mouth of the bay, where adult populations tend not to occur. By placing light traps overnight at 10m depth, we effectively sampled Dungeness crab larvae throughout the bay. Understanding the relationship between larvae and adults is the first step in identifying how the establishment of a marine reserve may replenish stocks either within or outside the reserve.

DOES PROXIMITY TO POTENTIAL AMBUSH COVER AFFECT SELECTION OF BASKING SITE BY
THE RINGED SEAL (PHOCA HISPIDA)?

Amy Kamarainen 2002.


ABSTRACT
During the late spring and early summer months, ringed seals abandon their subnivean lairs and haul out on the surface of the ice where they are vulnerable to their most significant predator, the polar bear (Ursus maritimus). I tested the hypothesis that ringed seals preferentially bask at sites farther away from potential polar bear ambush cover.
Sixty-two ringed seal holes, located by trained Labrador retrievers in the southern Beaufort Sea, were categorized as lairs or breathing holes. The same sites were visited later in the season (late May and early June), and evidence of use as a basking site was recorded. The distance from the hole to the nearest hummock (i.e. potential ambush cover) was measured. Seals preferred to haul out at sites that had been used as breathing holes as opposed to those that were lairs. The mean distance to the nearest hummock was greater at sites that were breathing holes than sites that were lairs. It was not possible, however, to rule out differences in snow depth as a confounding factor in preferential basking at breathing holes opposed to lairs.

EFFECTS OF GLACIAL ICE ON HARBOR SEAL NUMBERS IN JOHNS HOPKINS INLET, GLACIER BAY

Elizabeth Mathews, Jeffrey LeBrun and Lindsay Martin 2002.


ABSTRACT
Harbor seal numbers in Johns Hopkins Inlet in Glacier Bay National Park, Alaska have declined by 75% since the mid 1990's for reasons that are not yet known. In this tidewater glacial fjord, harbor seals rest on floating ice from Johns Hopkins glacier during pupping (June), breeding (July), and molting (July-August), and a reduction in the quantity of glacial ice, at some level, will limit the number of seals that use this breeding area. To test the hypothesis that seal numbers are currently limited by the amount of drifting glacial ice, photographic panoramas of the inlet were taken during daily counts of seals made from 1995 to 2001. We divided each panorama into four subareas (Fig. 1) and ranked the percent ice cover in subareas from 0 to 4 (0 = <=5%, 1 = 6-25%, 2 = 26-50%, 3 = 51-75%, 4 = 76-100%). We then tested for a correlation between total seal counts (mean of 2 paired counts) and ice cover for all subareas together and by each subarea alone for 93 counts from 1995 to 2001. We found no correlation between seal counts and the overall percent ice cover (p = 0.56, r2 = 0.004), nor for any of the subareas alone. In subsequent analyses we recommend that counts of seals by subarea (rather than the total counts) be tested against corresponding ice cover zones, as this would provide a more sensitive test of the influence of ice habitat on numbers of seals. These results strongly suggest that seals in Johns Hopkins Inlet are not currently limited by the availability of resting substrate and that the decline is more likely due to other factors. We cannot be certain, however, that our percent ice cover estimates are a good proxy for what makes an ice berg good habitat for a seal.

Figure 1. Aerial view chart and lateral view photographic panorama of Johns Hopkins Inlet, Glacier Bay showing the subareas used to categorize ice cover.

Figure 2. Total counts of harbor seals (mean of paired counts, n = 93) compared to the overall percent ice cover (scored as one of 5 categorical values) in Johns Hopkins Inlet, 1995 - 2001. We found no relationship between overall ice cover (nor for any one subarea) and the total number of seals (Simple Regression: y = 2382.5 - 82.1x, r2 = 0.004, p = 0.56). Intermediate values of ice cover categories occur because we use the mean ice cover score from 4 subareas (Fig. 1).

A COMPARISON OF LIGHT TRAPS AND PLANKTON TOWS FOR SAMPLING CRAB LARVAE IN BARTLETT COVE, ALASKA

Stephanie Porter, Ginny Eckert, Carrie Byron, Jennifer Fisher 2002.

Abstract and Poster presented at the Society for Comparative Biology Conference, Toronto, Ontario. Jan. 4-8, 2003.


ABSTRACT
We compared the efficiency of light-aggregation devices (light traps) and plankton tows for sampling crab larvae off the dock in Bartlett Cove, Glacier Bay National Park, Alaska. Three 10 hour light trap samples and three 5 minute plankton tow samples were compared each night of the study during three days in July and August of 2001, and July, August and September of 2002. Both methods captured both early and late stage larvae for all five major crab taxa present in the cove. However, light traps collected brachyuran megalopae that were not collected by the plankton tows, which suggests that the megalopae may evade plankton nets. The light trap technique was faster to use in the field and its selective method of sampling made it easier to process samples in the lab. The major disadvantage of the light traps was that they did not yield a quantitative measure of abundance, because the volume of water they sample could not be determined. However, the light traps did yield a relative abundance that could be compared over space and/or time. This evaluation of light traps, a relatively novel marine sampling device for temperate marine invertebrate larvae, compared to plankton tows, a standardized method of collection, may aid future attempts to characterize the temporal and spatial distributions of planktonic crab larvae in Glacier Bay.

A Comparative Study on the Presence of Ecdysteroids in Invertebrates

Margaret Sexton 2002.

ABSTRACT
In order to grow, members of the Phylum Arthropoda must first shed their exoskeletons. This molting process is mediated by the steroid 20-hydroxyecdysone, a derivative of ecdysone, which is one of multiple ecdysteroids produced by the Y-organ in arthropods. The production and function of ecdysteroids have been studied with respect to their role in promoting molting in insects and crustaceans. However, ecdysteroids have also been identified in several other Phyla that contain groups of animals that don't molt. These phyla include Mollusca, Annelida, Nematoda, Platyhelminthes, and Nemertea . The presence of ecdysteroids in non-arthropod phyla may have evolutionary implications. The steroids produced in non-arthropod phyla are the same as those produced in arthropods. Ecdysteroids may be active in the reproduction, growth, and development of these phyla, though specific physiological roles have not yet been identified. By measuring ecdysteroids in a variety of phyla, this study attempts to define biochemical similarities among these groups of animals. This information may have implications in the areas of phylogeny and comparative endocrinology.

DIEL ACTIVITY PATTERNS AMONG INDIVIDUAL RINGED SEALS, PHOCA HISPIDA

Daniella Swenton 2002.

ABSTRACT
Population estimates of the ringed seal, Phoca hispida, are difficult to obtain, because the animal spends much of its time underwater and in lairs under snow cover. In order to estimate population size, the proportion of time seals are visible to surveyors must be quantified. We examined the diel rhythms of individuals as seals abandoned subnivean lairs and began resting in the open on the ice surface. We documented the haul-out behavior of 14 ringed seals over the 24-hour cycle. We radio tagged the seals and tracked them on the shorefast ice of the Beaufort Sea from May 2, 2002 through June 19, 2002. We determined their behavior by visual observation. Results indicate that haul-out time in lairs is highly variable among individuals. When seals haul-out to bask on the ice, however, their individual diel rhythms synchronize.

CAN FUNGAL PATCHES ON STELLER SEA LIONS BE USED AS IDENTIFYING MARKS?

Julie Wright, Karen Blejwas. 2002.

ABSTRACT
Mark-recapture experiments have been done with Steller sea lions by tagging, branding, or dyeing the animals, but these methods are invasive, potentially harmful, and require physically capturing the animals. One alternative to marking animals is to identify individuals based on their natural markings, such as pelage patterns, flipper shape, and scars. The most distinct marks on Steller sea lions are fungal patches. These patches are believed to be "scars" left by active fungal infections, although the species of the fungus at work is still unknown. Based on a survey of veterinary reports of skin fungal infections in captive sea lions, I determined that the most probable cause of the skin infections is the fungus Trichophyton mentagrophytes. In order to use fungal patches for identification purposes, it is important to determine when fungal patches appear in an individual's lifespan, how long they last, if they are affected by molting, and if the size or shape of the fungal patches changes over time. These factors were assessed using a photographic database of branded animals made available by the Alaska Department of Fish and Game Department. Out of 87 animals sighted in 2 or more years between 2000 and 2002, 13.7% had visible fungal patches on them. Fungal patches visible in one year were visible in subsequent years, although one patch appeared to fade over time. Fungal patches appear to be reliable marks for photographic identification, at least for short-term studies of up to three years.

Salt and Salmon: the Effects of Hard Water Ions on Fertilization

Pamela Brannock, Michael Stekoll, Barbi Failor, Ivan Wang. 2001.

Poster and Abstract from the Aquatic Sciences Meeting. American Society of Limnology and Oceanography. Hawaii.

ABSTRACT
Mine effluents contain a variety of ionic species that may be harmful to important organisms living in the discharge area. In this study the industrial effluent from the Red Dog Mine (near Kotzebue, AK) was modeled in the laboratory in order to determine the response of developing salmon to this specific effluent. Previous experiments demonstrated that an increase in total dissolved solids (TDS) in the simulated mine effluent caused a decrease in the fertilization rate of exposed salmon eggs. The current study attempted to determine which specific ionic species were responsible for this decrease in fertilization. Concentrations of K+, Ca+2, SO4=, and Mg+2 typical of their presence in a 2500 ppm mine simulation effluent were tested in a salmon egg fertilization experiment. Since previous experiments demonstrated that NaCl at the same osmotic equivalent as the 2500 ppm solution has no effect on salmon fertilization, counter ions were selected to be Na+ and Cl-. Compounds utilized in this experiment were Na2SO4, CaCl2, MgCl2, and KCl. A set of 24-hour assays was preformed on both king and pink salmon provided by Douglas Island Pink and Chum, Inc. (DIPAC) Macaulary Hatchery in Juneau, AK. Treatments consisted of the molar equivalents of the chemical species in the 2500 ppm TDS concentration, four times that amount, and ¼ that amount. A 2500ppm solution and process water from Salmon Creek (the water supply that feeds the hatchery) were run as controls. Assays illustrated that both CaCl2 and Na2SO4, had the greatest detrimental effect on egg fertilization. This result suggests that Ca+2 and SO4= are responsible for the main effect in the simulated mine effluent. But caution is advised due to the confounding effect of Na+and Cl- ions at such high concentrations.