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Kristin S. Simac

Publications and source records attributed to Kristin S. Simac.

18 recordsLinked to original sources
USGS2021

Survival and abundance of polar bears in Alaska’s Beaufort Sea, 2001–2016

The Arctic Ocean is undergoing rapid transformation toward a seasonally ice-free ecosystem. As ice-adapted apex predators, polar bears ( Ursus maritimus ) are challenged to cope with ongoing habitat degradation and changes in their prey base driven by food-web response to climate warming. Knowledge of polar bear response to environmental change is necessary to understand ecosystem dynamics and inform conservation decisions. In the southern Beaufort Sea (SBS) of Alaska and western Canada, sea ice extent has declined since satellite observations began in 1979 and available evidence suggests that the carrying capacity of the SBS for polar bears has trended lower for nearly two decades. In this study, we investigated the population dynamics of polar bears in Alaska's SBS from 2001 to 2016 using a multistate Cormack–Jolly–Seber mark–recapture model. States were defined as geographic regions, and we used location data from mark–recapture observations and satellite-telemetered bears to model transitions between states and thereby explain heterogeneity in recapture probabilities. Our results corroborate prior findings that the SBS subpopulation experienced low survival from 2003 to 2006. Survival improved modestly from 2006 to 2008 and afterward rebounded to comparatively high levels for the remainder of the study, except in 2012. Abundance moved in concert with survival throughout the study period, declining substantially from 2003 and 2006 and afterward fluctuating with lower variation around an average of 565 bears (95% Bayesian credible interval [340, 920]) through 2015. Even though abundance was comparatively stable and without sustained trend from 2006 to 2015, polar bears in the Alaska SBS were less abundant over that period than at any time since passage of the U.S. Marine Mammal Protection Act. The potential for recovery is likely limited by the degree of habitat degradation the subpopulation has experienced, and future reductions in carrying capacity are expected given current projections for continued climate warming.

Alaska↗
USGS2021

Long-term variation in polar bear body condition and maternal investment relative to a changing environment

In the Arctic, warming air and ocean temperatures have resulted in substantial changes to sea ice, which is primary habitat for polar bears ( Ursus maritimus ). Reductions in extent, duration, and thickness have altered sea ice dynamics, which influences the ability of polar bears to reliably access marine mammal prey. Because nutritional condition is closely linked to population vital rates, a progressive decline in access to prey or an increase in the energetic cost of accessing prey has the potential to adversely affect polar bear population dynamics. We examined long-term (1983–2015) patterns of spring body condition (indexed using residual body mass) and maternal investment (i.e., litter mass of cubs-of-the-year and yearlings; COY and YRL) of polar bears from Alaska’s southern Beaufort Sea to evaluate potential relationships with regional- and circumpolar-scale sea ice conditions and atmospheric patterns. The length of the summer open-water (OW) season (i.e., the period of time the sea ice is mostly absent from the continental shelf) increased at a rate of 18 days decade -1 over the study period. However, the OW season duration was not a strong determinant of spring residual body mass or litter mass. Residual body mass of independent (i.e., subadults and adults) female bears varied relative to age class, reproductive status, and the strength of the prior winter’s Arctic Oscillation (i.e., a circumpolar-scale mode of climate variability driven by long-term atmospheric patterns). Spring residual mass of independent males varied with age class and variation in wind speed (i.e., regional-scale short-term atmospheric patterns) during the winter of the year preceding capture. Over the study period, mean annual body mass of adult females unaccompanied by COY declined by 4 kg/ decade -1 , while no temporal trends were evident in the mean annual body mass of adult females with COY, adult males, and subadults. Litter mass of COY varied relative to capture date, maternal age class and mass, litter size, and year of capture. Litter mass of YRL varied with capture date, maternal age class and mass, litter size, variation in winter wind speed (the year of and year preceding capture), and the strength of the prior winter’s Arctic Oscillation. Mean annual litter mass of COY decreased at a rate of 2.6 kg decade -1 and declined 0.68 kg for every 10 kg reduction in maternal mass. No trend was evident in the mean annual litter mass of yearlings. These findings suggest a nuanced response of the southern Beaufort Sea polar bears to environmental change, where some demographic groups (e.g., adult males and subadults) are presently more resilient than others to changes in the Arctic marine ecosystem.

Alaska↗
USGS2020

Analyses on subpopulation abundance and annual number of maternal dens for the U.S. Fish and Wildlife Service on polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska

The long-term persistence of polar bears ( Ursus maritimus ) is threatened by sea-ice loss due to climate change, which is concurrently providing an opportunity in the Arctic for increased anthropogenic activities including natural resource extraction. Mitigating the risk of those activities, which can adversely affect the population dynamics of the southern Beaufort Sea (SBS) subpopulation, is an emerging challenge as polar bears become more reliant on land and come into more frequent contact with humans. The Marine Mammal Protection Act and Endangered Species Act require the U.S. Fish and Wildlife Service to determine whether industrial activities will have a negligible impact on the SBS subpopulation. Information important to making that determination includes estimates of subpopulation abundance and the number of maternal dens likely to be present in areas where industrial activities occur. We analyzed mark-recapture data collected from SBS polar bears sampled in Alaska during 2001–16 using multistate Cormack-Jolly-Seber models. Estimated survival rates were relatively high during 2001–03, lower during 2004–08, then higher during 2009–15 except for 2012. Estimated abundance in the Alaska part of the SBS was consistent with the estimated survival rates, declining from about 1,300 bears in 2003 to 525 bears in 2006 and then remaining generally stable during 2006–15. The point estimate for the Alaska part of the SBS in 2015, the last year in which abundance could be estimated, was 573 bears (95-percent credible interval = 232, 1,140 bears). To estimate the expected number of terrestrial dens likely to be present in a given region in a given year, we used a Bayesian modeling approach based on calculations derived from SBS demographic and denning data. We estimated that the entire SBS subpopulation produced 123 dens per year (median; 95-percent credible interval = 69, 198 dens), 66 (median; 95-percent credible interval = 35, 110 dens) of which were land-based. Most land-based dens were located between the Colville and Canning Rivers (which includes the Prudhoe Bay-Kuparuk industrial footprint), followed by the 1002 Area of the Arctic National Wildlife Refuge and the National Petroleum Reserve-Alaska.

Alaska↗
USGS2020

Identifying reliable indicators of fitness in polar bears

Animal structural body size and condition are often measured to evaluate individual health, identify responses to environmental change and food availability, and relate food availability to effects on reproduction and survival. A variety of condition metrics have been developed but relationships between these metrics and vital rates are rarely validated. Identifying an optimal approach to estimate the body condition of polar bears is needed to improve monitoring of their response to decline in sea ice habitat. Therefore, we examined relationships between several commonly used condition indices (CI), body mass, and size with female reproductive success and cub survival among polar bears ( Ursus maritimus ) measured in two subpopulations over three decades. To improve measurement and application of morphometrics and CIs, we also examined whether CIs are independent of age and structural size–an important assumption for monitoring temporal trends—and factors affecting measurement precision and accuracy. Maternal CIs and mass measured the fall prior to denning were related to cub production. Similarly, maternal CIs, mass, and length were related to the mass of cubs or yearlings that accompanied her. However, maternal body mass, but not CIs, measured in the spring was related to cub production and only maternal mass and length were related to the probability of cub survival. These results suggest that CIs may not be better indicators of fitness than body mass in part because CIs remove variation associated with body size that is important in affecting fitness. Further, CIs exhibited variable relationships with age for growing bears and were lower for longer bears despite body length being related to cub survival and female reproductive success. These results are consistent with findings from other species indicating that body mass is a useful metric to link environmental conditions and population dynamics.

PLoS ONE↗
USGS2019

Reference intervals for blood-based biochemical analytes of southern Beaufort Sea polar bears

Accurate reference intervals (RI) for commonly measured blood-based analytes are essential for health monitoring programs. Baseline values for a panel of analytes can be used to monitor physiologic and pathophysiologic processes such as organ function, electrolyte balance, and protein catabolism. Our reference population includes 651 serum samples from polar bears (Ursus maritimus) from the southern Beaufort Sea subpopulation sampled in Alaska, USA, between 1983 - 2016. To establish RI for 13 biochemical analytes, we defined specific criteria for characterizing the reference population and relevant subgroups. To account for differences in seasonal life history characteristics, we determined separate RI for the spring and fall seasons, when prey availability and energetic requirements of bears differ. We established RI for five subgroups in spring based on sex, age class, and denning status, and three subgroups in fall based on sex and age class in females. Alkaline phosphatase activities were twice as high in subadult as in adult polar bears in spring (zmales = 4.08, Pmales < 0.001, zfemales = 3.90, Pfemales < 0.001), and did not differ between seasons. Denning females had significantly higher glucose concentrations than non-denning females (z = 4.94, P < 0.001), possibly reflecting differences in energy expenditure during lactation. Ten of the 13 analytes differed significantly between seasons in either males or females; however, the physiologic importance of these differences may be minimal. Establishing these RI allows for temporal monitoring of polar bear health in the southern Beaufort Sea and may prove useful for assessing and monitoring additional polar bear subpopulations in a changing Arctic environment.

Alaska↗
USGS2017

Spring fasting behavior in a marine apex predator provides an index of ecosystem productivity

The effects of declining Arctic sea ice on local ecosystem productivity are not well understood but have been shown to vary inter-specifically, spatially, and temporally. Because marine mammals occupy upper trophic levels in Arctic food webs, they may be useful indicators for understanding variation in ecosystem productivity. Polar bears ( Ursus maritimus ) are apex predators that primarily consume benthic and pelagic-feeding ice-associated seals. As such, their productivity integrates sea ice conditions and the ecosystem supporting them. Declining sea ice availability has been linked to negative population effects for polar bears but does not fully explain observed population changes. We examined relationships between spring foraging success of polar bears and sea ice conditions, prey productivity, and general patterns of ecosystem productivity in the Beaufort and Chukchi Seas (CSs). Fasting status (≥7 days) was estimated using serum urea and creatinine levels of 1,448 samples collected from 1,177 adult and subadult bears across three subpopulations. Fasting increased in the Beaufort Sea between 1983–1999 and 2000–2016 and was related to an index of ringed seal body condition. This change was concurrent with declines in body condition of polar bears and observed changes in the diet, condition and/or reproduction of four other vertebrate consumers within the food chain. In contrast, fasting declined in CS polar bears between periods and was less common than in the two Beaufort Sea subpopulations consistent with studies demonstrating higher primary productivity and maintenance or improved body condition in polar bears, ringed seals, and bearded seals despite recent sea ice loss in this region. Consistency between regional and temporal variation in spring polar bear fasting and food web productivity suggests that polar bears may be a useful indicator species. Furthermore, our results suggest that spatial and temporal ecological variation is important in affecting upper trophic-level productivity in these marine ecosystems.

Global Change Biology↗
USGS2017

Human-polar bear interactions in a changing Arctic: Existing and emerging concerns

The behavior and sociality of polar bears ( Ursus maritimus ) have been shaped by evolved preferences for sea ice habitat and preying on marine mammals. However, human behavior is causing changes to the Arctic marine ecosystem through the influence of greenhouse gas emissions that drive long-term change in ecosystem processes and via the presence of in situ stressors associated with increasing human activities. These changes are making it more difficult for polar bears to reliably use their traditional habitats and maintain fitness. Here, we provide an overview of how human activities in the Arctic are likely to change a polar bear’s behavior and to influence their resilience to environmental change. Developing a more thorough understanding of polar bear behavior and their capacity for flexibility in response to anthropogenic disturbances and subsequent mitigations may lead to successful near-term management interventions.

Book chapter↗
USGS2014

An experimental investigation of chemical communication in the polar bear

The polar bear ( U rsus maritimus ), with its wide-ranging movements, solitary existence and seasonal reproduction, is expected to favor chemosignaling over other communication modalities. However, the topography of its Arctic sea ice habitat is generally lacking in stationary vertical substrates routinely used for targeted scent marking in other bears. These environmental constraints may have shaped a marking strategy, unique to polar bears, for widely dispersed continuous dissemination of scent via foot pads. To investigate the role of chemical communication, pedal scents were collected from free-ranging polar bears of different sex and reproductive classes captured on spring sea ice in the Beaufort and Chukchi seas, and presented in a controlled fashion to 26 bears in zoos. Results from behavioral bioassays indicated that bears, especially females, were more likely to approach conspecific scent during the spring than the fall. Male flehmen behavior, indicative of chemosignal delivery to the vomeronasal organ, differentiated scent donor by sex and reproductive condition. Histologic examination of pedal skin collected from two females indicated prominent and profuse apocrine glands in association with large compound hair follicles, suggesting that they may produce scents that function as chemosignals. These results suggest that pedal scent, regardless of origin, conveys information to conspecifics that may facilitate social and reproductive behavior, and that chemical communication in this species has been adaptively shaped by environmental constraints of its habitat. However, continuously distributed scent signals necessary for breeding behavior may prove less effective if current and future environmental conditions cause disruption of scent trails due to increased fracturing of sea ice.

Journal of Zoology↗
USGS2014

Effects of capturing and collaring on polar bears: findings from long-term research on the southern Beaufort Sea population

Context: The potential for research methods to affect wildlife is an increasing concern among both scientists and the public. This topic has a particular urgency for polar bears because additional research is needed to monitor and understand population responses to rapid loss of sea ice habitat. Aims: This study used data collected from polar bears sampled in the Alaska portion of the southern Beaufort Sea to investigate the potential for capture to adversely affect behaviour and vital rates. We evaluated the extent to which capture, collaring and handling may influence activity and movement days to weeks post-capture, and body mass, body condition, reproduction and survival over 6 months or more. Methods: We compared post-capture activity and movement rates, and relationships between prior capture history and body mass, body condition and reproductive success. We also summarised data on capture-related mortality. Key results: Individual-based estimates of activity and movement rates reached near-normal levels within 2–3 days and fully normal levels within 5 days post-capture. Models of activity and movement rates among all bears had poor fit, but suggested potential for prolonged, lower-level rate reductions. Repeated captures was not related to negative effects on body condition, reproduction or cub growth or survival. Capture-related mortality was substantially reduced after 1986, when immobilisation drugs were changed, with only 3 mortalities in 2517 captures from 1987–2013. Conclusions: Polar bears in the southern Beaufort Sea exhibited the greatest reductions in activity and movement rates 3.5 days post-capture. These shorter-term, post-capture effects do not appear to have translated into any long-term effects on body condition, reproduction, or cub survival. Additionally, collaring had no effect on polar bear recovery rates, body condition, reproduction or cub survival. Implications: This study provides empirical evidence that current capture-based research methods do not have long-term implications, and are not contributing to observed changes in body condition, reproduction or survival in the southern Beaufort Sea. Continued refinement of capture protocols, such as the use of low-impact dart rifles and reversible drug combinations, might improve polar bear response to capture and abate short-term reductions in activity and movement post-capture.

Wildlife Research↗
USGS2013

Mapping polar bear maternal denning habitat in the National Petroleum Reserve -- Alaska with an IfSAR digital terrain model

The National Petroleum Reserve–Alaska (NPR-A) in northeastern Alaska provides winter maternal denning habitat for polar bears ( Ursus maritimus ) and also has high potential for recoverable hydrocarbons. Denning polar bears exposed to human activities may abandon their dens before their young are able to survive the severity of Arctic winter weather. To ensure that wintertime petroleum activities do not threaten polar bears, managers need to know the distribution of landscape features in which maternal dens are likely to occur. Here, we present a map of potential denning habitat within the NPR-A. We used a fine-grain digital elevation model derived from Interferometric Synthetic Aperture Radar (IfSAR) to generate a map of putative denning habitat. We then tested the map’s ability to identify polar bear denning habitat on the landscape. Our final map correctly identified 82% of denning habitat estimated to be within the NPR-A. Mapped denning habitat comprised 19.7 km2 (0.1% of the study area) and was widely dispersed. Though mapping denning habitat with IfSAR data was as effective as mapping with the photogrammetric methods used for other regions of the Alaskan Arctic coastal plain, the use of GIS to analyze IfSAR data allowed greater objectivity and flexibility with less manual labor. Analytical advantages and performance equivalent to that of manual cartographic methods suggest that the use of IfSAR data to identify polar bear maternal denning habitat is a better management tool in the NPR-A and wherever such data may be available.

Alaska↗
USGS2012

Long-distance swimming by polar bears (Ursus maritimus) of the southern Beaufort Sea during years of extensive open water

Polar bears ( Ursus maritimus Phipps, 1774) depend on sea ice for catching marine mammal prey. Recent sea-ice declines have been linked to reductions in body condition, survival, and population size. Reduced foraging opportunity is hypothesized to be the primary cause of sea-ice-linked declines, but the costs of travel through a deteriorated sea-ice environment also may be a factor. We used movement data from 52 adult female polar bears wearing Global Positioning System (GPS) collars, including some with dependent young, to document long-distance swimming (>50 km) by polar bears in the southern Beaufort and Chukchi seas. During 6 years (2004-2009), we identified 50 long-distance swims by 20 bears. Swim duration and distance ranged from 0.7 to 9.7 days (mean = 3.4 days) and 53.7 to 687.1 km (mean = 154.2 km), respectively. Frequency of swimming appeared to increase over the course of the study. We show that adult female polar bears and their cubs are capable of swimming long distances during periods when extensive areas of open water are present. However, long-distance swimming appears to have higher energetic demands than moving over sea ice. Our observations suggest long-distance swimming is a behavioral response to declining summer sea-ice conditions.

Canadian Journal of Zoology↗
USGS2006

Development of a murre (Uria spp.) egg control material

The Seabird Tissue Archival and Monitoring Project (STAMP) is a collaborative Alaska-wide effort by the US Fish and Wildlife Service's Alaska Maritime National Wildlife Refuge (USFWS/AMNWR), the US Geological Survey's Biological Resources Division (USGS/BRD), the Bureau of Indian Affairs Alaska Region Subsistence Branch (BIA/ARSB), and the National Institute of Standards and Technology (NIST) to monitor long-term (decadal) trends in environmental contaminants using seabird eggs. To support this effort, a matrix- (seabird egg) and concentration-specific control material was needed to ensure quality during analytical work. Although a herring gull egg quality assurance (HGQA) material is available from Environment Canada (EC), contaminant concentrations in this material tended to be higher than those observed in Alaskan murre (Uria spp.) eggs. Therefore, to prepare a more appropriate control material, a total of 12 common murre (U. aalge) and thick-billed murre (U. lomvia) eggs from four Bering Sea and Gulf of Alaska nesting locations were cryohomogenized to create 190 aliquots each containing approximately 6 g. This new control material was analyzed by different methods at NIST and EC facilities for the determination of concentrations and value assignment of 63 polychlorinated biphenyl (PCB) congeners, 20 organochlorine pesticides, and 11 polybrominated diphenyl ether (PBDE) congeners. The total PCB concentration is approximately 58 ng g -1 wet mass. Results obtained for analytes not listed on the certificates of analysis of the previously used control materials, HGQA and NIST's Standard Reference Material (SRM) 1946 Lake Superior Fish Tissue, are also presented. [Figure not available: see fulltext.]. ?? Springer-Verlag 2007.

Conference Paper↗
USGS2005

Murre eggs ( Uria aalge and Uria lomvia ) as indicators of mercury contamination in the Alaskan marine environment

Sixty common murre ( Uria aalge ) and 27 thick-billed murre ( Uria lomvia ) eggs collected by the Seabird Tissue Archival and Monitoring Project (STAMP) in 1999−2001 from two Gulf of Alaska and three Bering Sea nesting colonies were analyzed for total mercury (Hg) using isotope dilution cold vapor inductively coupled mass spectrometry. Hg concentrations (wet mass) ranged from 0.011 μg/g to 0.357 μg/g (relative standard deviation = 76%), while conspecifics from the same colonies and years had an average relative standard deviation of 33%. Hg levels in eggs from the Gulf of Alaska (0.166 μg/g ± 0.011 μg/g) were significantly higher ( p < 0.0001) than in the Bering Sea (0.047 μg/g ± 0.004 μg/g). Within the Bering Sea, Hg was significantly higher ( p = 0.0007) in eggs from Little Diomede Island near the arctic than at the two more southern colonies. Although thick-billed and common murres are ecologically similar, there were significant species differences in egg Hg concentrations within each region ( p < 0.0001). In the Bering Sea, eggs from thick-billed murres had higher Hg concentrations than eggs from common murres, while in the Gulf of Alaska, common murre eggs had higher concentrations than those of thick-billed murres. A separate one-way analysis of variance on the only time−trend data currently available for a colony (St. Lazaria Island in the Gulf of Alaska) found significantly lower Hg concentrations in common murre eggs collected in 2001 compared to 1999 ( p = 0.017). Results from this study indicate that murre eggs may be effective monitoring units for detecting geographic, species, and temporal patterns of Hg contamination in marine food webs. The relatively small intracolony variation in egg Hg levels and the ability to consistently obtain adequate sample sizes both within and among colonies over a large geographic range means that monitoring efforts using murre eggs will have suitable statistical power for detecting environmental patterns of Hg contamination. The potential influences of trophic effects, physical transport patterns, and biogeochemical processes on these monitoring efforts are discussed, and future plans to investigate the sources of the observed variability are presented.

Environmental Science & Technology↗
USGS2004

Using Forward Looking Infrared (FLIR) imagery to detect polar bear maternal dens: Operations manual

Recent research has shown that Forward Looking Infia-Red (FLIR) imagery can detect polar bear dens despite total snow cover over their deming habitat. FLIR imagers detect a AT or difference in temperature between objects in the imager's field of view. During the Arctic winter, the groundlsnow surface is typically cold, providing a dark background in the FLIR imager. Sources of heat appear as lighter or white areas. Dens, in particular, appear as small bright "hotspots", usually with kzy boundaries (Appendix 1). Most commonly, since bears chose deep snow drifts for deming, dens can be distinguished from the normally dark (cold) band of drifted snow surrounding them. This innovation has the potential to prevent human activities fiom disturbing deming polar bears by allowing managers to discover dens before potentially disruptive activities begin. This is important because expanding resource extraction in Alaska's Arctic regions may threaten the welfare of polar bears and their habitat. In recent years, exploration and development activities have expanded east and west of the original oil fields of Prudhoe Bay. Hydrocarbon extraction is now occurring or planned along much of the central Beaufort Sea coast. As development continues into the National Petroleum Reserve, the scope of expansion could include 213 of the northern coastal region of Alaska. Industrial activities are a potential threat to polar bears, especially as they might disturb bears in maternal dens (Lentfer and Hensel 1980, Stirling 1990, Stirling and Andriashek 1992, Amstrup 1993, Amstrup and Gardner 1994). As the number of humans and their activities have increased in recent years, there has been a concurrent increase in the number of female polar bears deming on land (Amstrup and Gardner 1994). Therefore, the probability of disrupting maternal deming can be expected to increase in the future. Using FLIR surveys to detect bears in dens could reduce or eliminate that probability. The purpose of this manual is to provide agency and private sector land managers with the information necessary to perform effective FLIR surveys to detect maternal dens. A list of personnel who can provide additional information is provided in Appendix 2.

BOEM↗
USGS2003

Seabird tissue archival and monitoring project: Egg collections and analytical results 1999-2002

In 1998, the U.S. Geological Survey Biological Resources Division (USGS-BRD), the U.S. Fish and Wildlife Service (USFWS) Alaska Maritime National Wildlife Refuge (AMNWR), and the National Institute of Standards and Technology (NIST) began the Seabird Tissue Archival and Monitoring Project (STAMP) to collect and cryogenically bank tissues from seabirds in Alaska for future retrospective analysis of anthropogenic contaminants. The approach of STAMP was similar to that of the Alaska Marine Mammal Tissue Archival Project (AMMTAP). AMMTAP was started in 1987 by NIST and the National Oceanic and Atmospheric Administration (NOAA) as part of the Outer Continental Shelf Environmental Assessment Program sponsored by the Minerals Management Service. Presently sponsored by the USGS-BRD, AMMTAP continues its work as part of a larger national program, the Marine Mammal Health and Stranding Response Program. AMMTAP developed carefully designed sampling and specimen banking protocols. Since 1987, AMMTAP has collected tissues from marine mammals taken in Alaska Native subsistence hunts and has cryogenically banked these tissues at the NIST National Biomonitoring Specimen Bank (NBSB). Through its own analytical work and working in partnership with other researchers both within and outside Alaska, AMMTAP has helped to develop a substantial database on contaminants in Alaska marine mammals. In contrast, data and information is limited on contaminants in Alaska seabirds, which are similar to marine mammals in that they feed near the top of the food chain and have the potential for accumulating anthropogenic contaminants. During its early planning stages, STAMP managers identified the seabird egg as the first tissue of choice for study by the project. There is a relatively long history of using bird eggs for environmental monitoring and for investigating the health status of bird populations. Since 1998, protocols for collecting and processing eggs, and cryogenically banking egg samples have been developed by STAMP (see York et al. 2001). Eggs are being collected on an annual basis for several species at nesting colonies throughout Alaska. Aliquots of these egg samples are being analyzed on a regular basis for persistent organic pollutants and mercury. Results of this work have been published in scientific journals (Christopher et al. 2002) and in conference proceedings (Kucklick et al. 2002; Vander Pol et al. 2002a, 2002b). The intent of this report is to provide an up-to-date description of STAMP. The report contains the most recent egg collection inventory, analytical data, preliminary interpretations based on these data, and a discussion of possible future directions of the project.

Report↗
USGS2003

Detecting denning polar bears with forward looking infra-red imagery (FLIR)

Polar bears give birth in snow dens in mid winter, and remain in dens until early spring. Survival and development of neonates is dependent on the stable environment within the maternal den. Petroleum related activities currently span approximately 200 km of the Alaskan Beaufort Sea coastal area. New and proposed developments are expected to dramatically expand the area influenced by petroleum activities. These activities are a potential threat to polar bears, especially as they might disturb denning females. In order to help manage and mitigate potential disruptions of polar bear denning, we tested whether we could detect heat, rising through the roofs of maternal dens, with forward-looking infrared (FLIR) viewing devices. We tested detectability of dens by flying transects, over habitats known to hold dens, with FLIR equipped aircraft. We recorded flight and weather conditions at each observation and tallied whether or not the den was detected.

Conference Paper↗
USGS2001

Seabird tissue archival and monitoring project: Protocol for collecting and banking seabird eggs

Archiving biological and environmental samples for retrospective analysis is a major component of systematic environmental monitoring. The long-term storage of carefully selected, representative samples in an environmental specimen bank is an important complement to the real-time monitoring of the environment. These archived samples permit: The use of subsequently developed innovative analytical technology that was not available at the time the samples were archived, for clear state-of-art identification an~ quantification of analytes of interest, The identification and quantification of analytes that are of subsequent interest but that were not of interest at the time the samples were archived, and The comparison of present and past analytical techniques and values, providing continued credibility of past analytical values, and allowing flexibility in environmental monitoring programs. Seabirds, including albatrosses, pelicans, cormorants, terns, kittiwakes, murres, guillemots, and puffins spend most of their lives at sea and have special adaptations for feeding in the marine environment, including the ability to excrete the excess salt obtained from ingesting seawater. Many species nest in dense groups (colonies) on steep, precipitous sea-cliffs and headlands. Seabirds are long-lived and slow to mature. They occupy high positions in the marine food web and are considered sensitive indicators for the marine environment (prey includes krill, small fish, and squid). Breeding success, timing of nesting, diets, and survival rates may provide early indications of changing environmental conditions (e.g., see Hatch et aI., 1993). Chemical analysis of seabird tissues, including egg contents, can be particularly useful in determining whether contaminants (and potential biological effects) associated with human industrial activities, such as offshore petroleum and mineral exploration and development, are accumulating in marine environments. The collection and archival of seabird tissues over a period of several years will be a resource for future analyses, providing samples that can be used to determine historical baseline contaminant levels.

Report↗