2008 Graduate Student Research Award - Top Five Ph.D. applicants
Applicant: Mary Hunsicker, University of Washington
Project Title: Evaluating the trophic role of the commander squid, Berryteuthis magister, and the
factors regulating squid abundance in the eastern Bering Sea continental slope ecosystem
Abstract: Squid are a key component of marine food webs, providing sustenance for fishes,
seabirds, and marine mammals worldwide. Despite their potential to influence the dynamics of
commercial and conservation species through trophic pathways, there are critical gaps in our
understanding of the role of squid in marine ecosystems. The proposed work will begin to these
address these gaps by evaluating the role of the commander squid, Berryteuthis magister, in the
eastern Bering Sea (EBS) continental slope ecosystem. The first component of this project will
examine the trophic position and feeding ecology of B. magister using stomach content and stable
isotope analyses. Particular attention will be paid to how feeding habits vary with body size and
season, and whether ontogenetic shifts in trophic position can be detected from the isotopic
signatures in B. magister eye lens layers. The second component of this project will examine the
potential physical factors regulating the abundance of B. magister by modeling the relationship
between the spatio-temporal patterns of squid by-catch in the mid-water pollock fishery and
environmental conditions in the EBS. Better knowledge of trophic interactions and the factors
regulating pelagic forage species is needed to effectively manage fisheries in the EBS and to
develop hypotheses concerning the impact of changing climate conditions on this ecosystem.
Applicant: Markus Janout, University of Alaska Fairbanks
Project Title: Atmospheric and Oceanic Contributions on Ocean Temperatures in the Northern
Gulf of Alaska
Abstract: The objective of this project is to quantify the processes controlling temperature on the
northern Gulf of Alaska (GOA) shelf. In particular, I propose to assess the relative contributions
of atmosphere and oceanic heat advection to the northern GOA’s heat budget, examine crossshelf gradients and interannual variability in heat fluxes, and hindcast shelf temperatures back to
1948. The results will enhance our understanding of the physical environment of the northern
GOA shelf and how this marine ecosystem may respond to a changing climate. The northern
GOA shelf supports important fisheries, with great commercial and traditional value for Alaska.
Ocean temperatures influence most aspects of an ecosystem, from physiology and behavior of
individual species to their physical environment and food production. The 1976/77 “regime shift”
marked a period of sudden warming of northern GOA waters and the beginning of a sharp
transition from a shrimp/crab dominated ecosystem to one governed by pelagic fishes. This
(possibly temperaturecontrolled) ecosystem shift had significant economic consequences for the
GOA fishing industry and imposed new strains on management agencies. Successful ecosystem
management requires understanding how ocean temperatures might evolve under a changing
climate. This, however, requires understanding the processes controlling ocean temperature.
Since the 1970’s, temperatures in the GOA have increased by ~0.8ºC. Ocean-atmosphere
circulation models predict warmer and wetter winters for the subarctic North Pacific, leading to
ocean warming through decreased winter ocean-atmosphere heat fluxes. The warming of GOA
waters could potentially be amplified by increased oceanic heat advection by the Alaska Coastal
Current, with uncertain consequences for GOA and Bering Sea fish stocks.
2008 Graduate Student Research Award - Top Five Ph.D. applicants
Applicant: Briana Witteveen, University of Alaska Fairbanks/University of Central
Florida
Project Title: Using Stable Isotopes to Assess Population Structure and Feeding Ecology of
North Pacific Humpback Whales (Megaptera novaeangliae)
Abstract: North Pacific humpback whales are a migratory species known to have a complex
population structure on both feeding and breeding grounds. This project uses techniques in stable
isotope ecology to explore this population structure. Specifically, this project evaluates the utility
in using stable carbon (δ13C) and stable nitrogen (δ15N) isotope ratios of skin collected from
free-ranging humpback whales as a means for describing aspects of their distribution, migration
patterns, foraging habits, and prey preferences. Skin from biopsy samples collected as a part of
the Structure of Populations, Levels of Abundance, and Status of Humpback whales (SPLASH)
project from all known seasonal feeding and breeding areas throughout the North Pacific have
been analyzed for δ15N and δ13C. Additional samples analyzed were collected near Kodiak
Island, Alaska as a part of the ongoing efforts of the Gulf Apex Predator prey (GAP) project
conducted through the University of Alaska Fairbanks. The methodologies utilized in this project
are being used to determine humpback whale migratory destinations without requiring
photographs of individuals on both feeding and breeding grounds. In addition, this project
provides essential data regarding relative trophic positions and relationships of humpback whales
to their prey in various regions throughout the North Pacific. Such information can be used to
evaluate the potential for resource competition between humpback whales and other marine
predators and improve upon predator-prey interaction models. Further, techniques of this project
can be applied to other species allowing for direct comparison of isotopic signatures of species
that may co-occur temporally and spatially. Overall, this project represents a rare opportunity for
broad spatial and temporal exploration of a marine mammal population and for comprehensive
application of stable isotope ecology.
Applicant: Jamie Womble, Oregon State University
Project Title: Intra-population variation in over-winter movement strategies of harbor seals
(Phoca vitulina richardii) from a glacial fjord system in the Gulf of Alaska
Abstract: The objectives of this study are to use satellite telemetry, remotely-sensed
oceanographic data, and individual-based models to quantitatively assess intra-population
variation in non-breeding season movement strategies and habitat use of juvenile harbor seals
from a glacial fjord system in Glacier Bay National Park (GBNP) in southeastern Alaska. GBNP
has historically supported one of the largest breeding populations of harbor seals in Alaska;
however, the number of seals has declined by up to 75% since 1992. The magnitude and rate of
the decline exceed all reported declines of harbor seals in Alaska, with the exception of that at
Tugidak Island. Approximately 2/3 of the harbor seal population in GBNP relies on glacial ice
emanating from an active tidewater glacier as a pupping and resting substrate; however, little is
known regarding basic ecology and movement patterns of seals using glacial ice sites. Rapid
deglaciation of over 100km in the past 225 years in GBNP is one of the most rapid on record and
may have demographic consequences for harbor seals that are dependent upon glacial ice as a
haulout substrate. This project represents the first effort to quantify spatially explicit nonbreeding season space use patterns of harbor seals from a glacial fjord system relative to
biophysical parameters. The nonbreeding season may be the most energetically challenging
period for juvenile harbor seals, thus understanding individual variability in movement tactics
relative to biophysical variables is critical. Ultimately, this project will contribute to our
2008 Graduate Student Research Award - Top Five Ph.D. applicants
knowledge of the ecology of harbor seals that occupy glacial fjord systems and will have
implications for the conservation and management of harbor seals stocks throughout Alaska.
Applicant: Rebecca Young, University of Alaska Fairbanks
Project Title: Development of molecular techniques for monitoring demographic structure of
Bering Sea seabird populations
Abstract: Demographic information is crucial to our understanding of the population dynamics
of toppredators in the Bering Sea. Persistent stress and low productivity due to climate- or
human-induced changes in food availability may result in drastic differences in the age structure
of declining and increasing populations of seabirds. The survival and reproductive performance
of long-lived seabirds are age-dependent, which in turn may affect their population responses to
environmental changes. However, we lack current information on the age structure of different
species at major seabird colonies, and our ability to monitor numerical trajectories of seabirds
breeding in the Bering Sea is also limited. There is an urgent need to develop a cost-effective tool
to monitor demographic changes in seabirds. The goal of this proposed study is to develop a new
tool for estimating the age of free-living Least Auklets (Aethia pusilla) and Thick-billed Murres
(Uria lomvia) –the most abundant species of seabirds breeding in the south-eastern Bering Sea.
We propose to use known-age captive populations in order to develop a tool for assessing the age
of a bird using a molecular technique. Specifically, we will measure the length of telomere
fragment in the red blood cells of known-age individuals. We will create an “age-dependent
telomere loss” profile for each species, showing the initial length of telomeres (in neonates) and
the age-dependent rate of telomere loss (in adults). These profiles will allow us to establish a
relationship between telomere length and age of auklets and murres. Once we developed this tool
for the focal species, we plan to use it to characterize changes in seabird demography at the
Pribilof Islands and other colonies in the Bering Sea as related to effects of climate change and
the fisheries industry.