Population biology and ecology of marine mammals, population estimation, predator/prey relations, carnivora, coastal marine ecology, marine conservation.
Professional Experience
2013 - Present Research Wildlife Biologist Emeritus, USGS, Alaska Science Center, Anchorage, Alaska
1990 - 2013 Research Wildlife Biologist, USGS, Alaska Science Center, Anchorage, Alaska
1989 - 1990 Wildlife Biologist, U.S. Fish & Wildlife Service, Koyukuk Wildlife Refuge, Galena, AK
1986 - 1989 Fish and Wildlife Biologist, National Ecology Research Center, Santa Cruz, CA
Education and Certifications
M.S. 1986 California Polytechnical University, San Luis Obispo, CA Biology
B.S. 1975 California State University, Long Beach, CA Wildlife Biology
Affiliations and Memberships*
Society for Conservation Biology
American Society of Mammalogy
Society for Marine Mammalogy
The Wildlife Society
Science and Products
Primary Production Sources and Bottom-up Limitations in Nearshore Ecosystems
Intertidal Temperature Data from Kachemak Bay, Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
Intertidal Mussel (Mytilus) Data from Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
Sea Otter Survey Data, Carcass Recovery Data, and Blood Chemistry Data from Southwest Alaska
Data for Gene Transcription Patterns in Response to Low Level Petroleum Contaminants in Mytilus trossulus from Field Sites and Harbors in Southcentral Alaska
Gulf Watch Alaska Nearshore Component: Monitoring Site Locations from Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
Lack of strong responses to the Pacific marine heatwave by benthivorous marine birds indicates importance of trophic drivers
Gene expression and wildlife health: Varied interpretations based on perspective
Revealing the extent of sea otter impacts on bivalve prey through multi-trophic monitoring and mechanistic models
Brown bear–sea otter interactions along the Katmai coast: Terrestrial and nearshore communities linked by predation
Where land and sea meet: Brown bears and sea otters
Evidence of increased mussel abundance related to the Pacific marine heatwave and sea star wasting
Sea otter foraging behavior
Translocations maintain genetic diversity and increase connectivity in sea otters, Enhydra lutris
Sea otter population collapse in southwest Alaska: Assessing ecological covariates, consequences, and causal factors
Sea otter (Enhydra lutris) populations in southwest Alaska declined substantially between about 1990 and the most recent set of surveys in 2015. Here we report changes in the distribution and abundance of sea otters, and covarying patterns in reproduction, mortality, body size and condition, diet and foraging behavior, food availability, health profiles, and exposure to environmental contaminants
Ecosystem response persists after a prolonged marine heatwave
Spatial epidemiological patterns suggest mechanisms of land-sea transmission for Sarcocystis neurona in a coastal marine mammal
Trends and carrying capacity of sea otters in Southeast Alaska
Science and Products
- Science
Primary Production Sources and Bottom-up Limitations in Nearshore Ecosystems
Kelp forests are among the world’s most productive habitats, but recent evidence suggests that production is highly variable. - Data
Intertidal Temperature Data from Kachemak Bay, Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
These data are part of the Gulf Watch Alaska (GWA) long-term monitoring program. This dataset consists of date, time, and temperature measurements from intertidal rocky sampling sites, including predicted tide height at the time of the reading, which is used to distinguish air from water temperature readings. The data are provided as comma separated values (.csv) files derived from data downloadedIntertidal Mussel (Mytilus) Data from Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
These data are part of the Gulf Watch Alaska (GWA) long-term monitoring program and describe mussel sampling and observations conducted in the northern Gulf of Alaska. This dataset consists of six comma separated files (.csv): 1) mussel sampling site layout information, 2) mussel counts for mussels greater than 20 millimeters in a quadrat, 3) mussel size measurements for mussels greater than 20 miSea Otter Survey Data, Carcass Recovery Data, and Blood Chemistry Data from Southwest Alaska
Three data sets are included here to aid in assessment of the sea otter population collapse in southwest Alaska. One data set consists of results of sea otter surveys conducted between 1959 and 2015 at Bering Island, Russia and a selection of western Aleutian Islands in Alaska. Sea otter counts are reduced to a comparable value of otters per linear kilometer. Another data set consists per-capita aData for Gene Transcription Patterns in Response to Low Level Petroleum Contaminants in Mytilus trossulus from Field Sites and Harbors in Southcentral Alaska
Marine mussels are a ubiquitous and crucial component of the nearshore environment, and new genomic technologies exist to quantify molecular responses of individual mussels to stimuli, including exposure to polycyclic aromatic hydrocarbons (PAHs). We used gene-based assays of exposure and physiological function to assess lingering oil damage from the 1989 Exxon Valdez oil spill using the Pacific bGulf Watch Alaska Nearshore Component: Monitoring Site Locations from Prince William Sound, Katmai National Park and Preserve, and Kenai Fjords National Park
These data are part of the Gulf Watch Alaska (GWA) long term monitoring program, nearshore monitoring component. Specifically, these data describe site locations for rocky intertidal, mussel sampling, soft sediment bivalve sampling, and eelgrass bed sampling in the northern Gulf of Alaska within the GWA program. The dataset consists of two comma separated files exported from a Microsoft Excel work - Publications
Filter Total Items: 136
Lack of strong responses to the Pacific marine heatwave by benthivorous marine birds indicates importance of trophic drivers
The Pacific marine heatwave (PMH) of 2014-2016 was an intense, long-lasting environmental disturbance expressed throughout the north Pacific. While dramatic consequences of the PMH on pelagic food webs have been well documented, effects on nearshore food webs, i.e., those based on macroalgae primary productivity, benthic invertebrate intermediate consumers, and specialized benthivorous top predatoAuthorsBrian H. Robinson, Heather A. Coletti, Brenda Ballachey, James L. Bodkin, Kimberly A. Kloecker, Sarah Beth Traiger, Daniel EslerGene expression and wildlife health: Varied interpretations based on perspective
We evaluated wildlife population health from the perspective of statistical means vs. variances. We outlined the choices necessary to provide the framework for our study. These consisted of spatial and temporal boundaries (e.g., choice of sentinel species, populations, time frame), measurement techniques (molecular to population level), and appropriate statistical analyses. We chose to assess theAuthorsLizabeth Bowen, Julie L. Yee, James L. Bodkin, Shannon C. Waters, Michael J. Murray, Heather Coletti, Brenda E. Ballachey, Daniel Monson, A. Keith MilesRevealing the extent of sea otter impacts on bivalve prey through multi-trophic monitoring and mechanistic models
Sea otters are apex predators that can exert considerable influence over the nearshore communities they occupy. Since facing near extinction in the early 1900s, sea otters are making a remarkable recovery in Southeast Alaska, particularly in Glacier Bay, the largest protected tidewater glacier fjord in the world. The expansion of sea otters across Glacier Bay offers both a challenge to monitoringAuthorsClinton B. Leach, Benjamin P. Weitzman, James L. Bodkin, Daniel Esler, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Jamie N. Womble, Mevin B. HootenBrown bear–sea otter interactions along the Katmai coast: Terrestrial and nearshore communities linked by predation
Sea otters were extirpated throughout much of their range by the maritime fur trade in the 18th and 19th centuries, including the coast of Katmai National Park and Preserve in southcentral Alaska. Brown bears are an important component of the Katmai ecosystem where they are the focus of a thriving ecotourism bear-viewing industry as they forage in sedge meadows and dig clams in the extensive tidalAuthorsDaniel Monson, Rebecca L. Taylor, Grant Hilderbrand, Joy Erlenbach, Heather Coletti, James L. BodkinWhere land and sea meet: Brown bears and sea otters
In Katmai National Park, Alaska, USA, we have seen changes in the number of brown bears and sea otters. The number of animals of a species a habitat can support is called carrying capacity. Even though bears live on land and sea otters live in the ocean, these two mammals share coastal habitats. Bears eat salmon, other fish, plants, clams, and beached whales. Sea otters feed on clams and other marAuthorsHeather Coletti, Grant Hilderbrand, James L. Bodkin, Brenda E. Ballachey, Joy Erlenbach, George G. Esslinger, Michael Hannam, Kimberly A. Kloecker, Buck Mangipane, Amy Miller, Daniel Monson, Benjamin Pister, K. Griffin, K. Bodkin, Tom SmithEvidence of increased mussel abundance related to the Pacific marine heatwave and sea star wasting
Mussels occupy a key middle trophic position in nearshore food webs linking primary producers to predators. Climate-related environmental changes may synergistically combine with changes in predator abundance to affect intertidal ecosystems. We examined the influence of two major events on mussel (Mytilus trossulus) abundance in the northern Gulf of Alaska: the recent Pacific marine heatwave (PMH,AuthorsSarah Beth Traiger, James L. Bodkin, Heather Coletti, Brenda Ballachey, Dean Thomas, Daniel Esler, Katrin Iken, Brenda Konar, Mandy Lindeberg, Daniel Monson, Brian H. Robinson, Robert M. Suryan, Ben WeitzmanSea otter foraging behavior
Sea otters are marine specialists but diet generalists, which feed primarily on benthic mega-invertebrates (i.e., body dimension >1 cm). They locate and capture epibenthic and infaunal prey with their forepaws by relying on vision and tactile sensitivity during short-duration dives (generally <2 min) in shallow waters (routine dives <30 m and maximum dive depth ~100 m) of the littoral zone. Sea otAuthorsRandall W. Davis, James L. BodkinTranslocations maintain genetic diversity and increase connectivity in sea otters, Enhydra lutris
Sea otters, Enhydra lutris, were once abundant along the nearshore areas of the North Pacific. The international maritime fur trade that ended in 1911 left 13 small remnant populations with low genetic diversity. Subsequent translocations into previously occupied habitat resulted in several reintroduced populations along the coast of North America. We sampled sea otters between 2008 and 2011 throuAuthorsShawn E. Larson, Roderick B. Gagne, James L. Bodkin, Michael J. Murray, Katherine Ralls, Lizabeth Bowen, Raphael Leblois, Sylvain Piry, Maria Cecilia Penedo, M. Tim Tinker, Holly B. ErnestSea otter population collapse in southwest Alaska: Assessing ecological covariates, consequences, and causal factors
Sea otter (Enhydra lutris) populations in southwest Alaska declined substantially between about 1990 and the most recent set of surveys in 2015. Here we report changes in the distribution and abundance of sea otters, and covarying patterns in reproduction, mortality, body size and condition, diet and foraging behavior, food availability, health profiles, and exposure to environmental contaminants
AuthorsM. Tim Tinker, James L. Bodkin, Lizabeth Bowen, Brenda Ballachey, Gena Bentall, Alexander Burdin, Heather Coletti, George G. Esslinger, Brian B. Hatfield, Michael C. Kenner, Kimberly A. Kloecker, Brenda Konar, A. Keith Miles, Daniel Monson, Michael J. Murray, Ben Weitzman, James A. EstesEcosystem response persists after a prolonged marine heatwave
Some of the longest and most comprehensive marine ecosystem monitoring programs were established in the Gulf of Alaska following the environmental disaster of the Exxon Valdez oil spill over 30 years ago. These monitoring programs have been successful in assessing recovery from oil spill impacts, and their continuation decades later has now provided an unparalleled assessment of ecosystem responseAuthorsRobert M. Suryan, Mayumi L. Arimitsu, Heather A. Coletti, Russell R. Hopcroft, Mandy Lindeberg, Steven J. Barbeaux, Sonia Batten, William J. Burt, Mary Anne Bishop, James L. Bodkin, R. Brenner, Robert W. Campbell, Daniel A. Cushing, Seth L. Danielson, Martin W. Dorn, Brie Drummond, Daniel Esler, Thomas S. Gelatt, Dana H. Hanselman, Katrin Iken, David B. Irons, Scott A. Hatch, Stormy Haught, Kris Holderied, David G. Kimmel, Brenda H. Konar, Kathy J. Kuletz, Arthur B. Kettle, Benjamin J. Laurel, John M. Maniscalco, Daniel Monson, Craig O. Matkin, Caitlin McKinstry, John Moran, D. Olsen, John F. Piatt, Wayne A. Palsson, W. Scott Pegau, Lauren A. Rogers, Nora A. Rojek, Anne Schaefer, Ingrid B. Spies, J.M. Straley, Suzanne L. Strom, Marysia Szymkowiak, Ben P. Weitzman, Kathryn L. Sweeney, Ellen M. Yasumiishi, Stephanie ZadorSpatial epidemiological patterns suggest mechanisms of land-sea transmission for Sarcocystis neurona in a coastal marine mammal
Sarcocystis neurona was recognised as an important cause of mortality in southern sea otters (Enhydra lutris nereis) after an outbreak in April 2004 and has since been detected in many marine mammal species in the Northeast Pacific Ocean. Risk of S. neurona exposure in sea otters is associated with consumption of clams and soft-sediment prey and is temporally associated with runoff events. We examAuthorsTristan Burgess, M. Tim Tinker, Melissa A. Miller, Woutrina A. Smith, James L. Bodkin, Michael J. Murray, Linda M. Nichol, Justin A. Saarinen, Shawn E. Larson, Joseph A. Tomoleoni, Patricia A. Conrad, Christine K. JohnsonTrends and carrying capacity of sea otters in Southeast Alaska
Sea otter populations in Southeast Alaska (SEAK) have increased dramatically from fewer than 500 translocated animals in the late 1960s. The recovery of sea otters to ecosystems from which they had been absent has affected coastal food webs, including commercially important fisheries, and thus information on expected growth and equilibrium abundances can help inform resource management. We compileAuthorsM. Tim Tinker, Verena A. Gill, George G. Esslinger, James L. Bodkin, Melissa Monk, Marc Mangel, Daniel Monson, Wendel W. Raymond, Michelle Kissling - News
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government