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Fish & Wildlife Disease: Marine Mammals

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By Biological Threats and Invasive Species Research Program September 29, 2022

We are developing advanced tools for disease diagnosis, surveillance, risk assessment and control to support management of wildlife diseases.

Marine Mammal Disease Research

Sea otter Elkhorn Slough National Estuarine Research Reserve (WERC)

Population Biology and Behavior of Sea Otters

WERC's sea otter researchers are developing and utilizing a variety of methodological and analytical tools to understand the causes of biological and ecological trends in sea otter populations, and to predict the ecological consequences of management practices on these populations and their ecosystems.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Species Management Research Program, Western Ecological Research Center (WERC)
Population Biology and Behavior of Sea Otters

Population Biology and Behavior of Sea Otters

WERC's sea otter researchers are developing and utilizing a variety of methodological and analytical tools to understand the causes of biological and ecological trends in sea otter populations, and to predict the ecological consequences of management practices on these populations and their ecosystems.
Learn More
WERC Sea otter research in Big Sur, California

California Sea Otter Stranding Network

The California Sea Otter Stranding Network is part of the USGS effort to monitor southern sea otters (Enhydra lutris nereis) and provide data to the U.S. Fish and Wildlife Service. WERC's sea otter team works with multiple institutions and partners to report, recover, and examine stranded sea otters. In addition, instructions on how to report a stranded sea otter are included in this webpage.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Species Management Research Program, Western Ecological Research Center (WERC)
California Sea Otter Stranding Network

California Sea Otter Stranding Network

The California Sea Otter Stranding Network is part of the USGS effort to monitor southern sea otters (Enhydra lutris nereis) and provide data to the U.S. Fish and Wildlife Service. WERC's sea otter team works with multiple institutions and partners to report, recover, and examine stranded sea otters. In addition, instructions on how to report a stranded sea otter are included in this webpage.
Learn More

Explore our science using the data below.

Sea Otter Survey Data, Carcass Recovery Data, and Blood Chemistry Data from Southwest Alaska Sea 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...
By
Western Ecological Research Center (WERC)

Necropsy reference number and summary collection information for Washington state population of northern sea otters examined during 1989-2010 Necropsy reference number and summary collection information for Washington state population of northern sea otters examined during 1989-2010

Morbillivirus epidemics in marine mammals first gained prominence in 1988 when an outbreak of phocine distemper virus (PDV) occurred in European harbor seals (Phoca vitulina vitulina). Prior to 2001, all serosurveys for morbilliviruses in sea otters (Enhydra lutris) in California, Washington and Alaska documented a 0% seroprevalence. The first published serodetections of morbillivirus in...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center

Explore our science using the publications below.

Tool use increases mechanical foraging success and tooth health in southern sea otters (Enhydra lutris nereis) Tool use increases mechanical foraging success and tooth health in southern sea otters (Enhydra lutris nereis)

Although tool use may enhance resource utilization, its fitness benefits are difficult to measure. By examining longitudinal data from 196 radio-tagged southern sea otters (Enhydra lutris nereis), we found that tool-using individuals, particularly females, gained access to larger and/or harder-shelled prey. These mechanical advantages translated to reduced tooth damage during food...
Authors
Chris J. Law, M. Tim Tinker, Jessica A. Fujii, Teri Nicholson, Michelle M. Staedler, Joseph A. Tomoleoni, Colleen Young, Rita S. Mehta
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Gene expression and wildlife health: Varied interpretations based on perspective Gene 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...
Authors
Lizabeth Bowen, Julie L. Yee, James L. Bodkin, Shannon C. Waters-Dynes, Michael J. Murray, Heather Coletti, Brenda E. Ballachey, Daniel Monson, A. Keith Miles
By
Ecosystems Mission Area, Alaska Science Center, Western Ecological Research Center (WERC)

Divergent gene expression profiles in Alaskan sea otters: An indicator of chronic domoic acid exposure? Divergent gene expression profiles in Alaskan sea otters: An indicator of chronic domoic acid exposure?

An opportunistic investigation into ecosystem instability in Kachemak Bay (KBay), Alaska, has led us to investigate exposure to toxic algae in sea otters. We used gene expression to explore the physiological health of sea otters sampled in KBay in May 2019. We found altered levels of gene transcripts in comparison with reference sea otters from clinically normal, oil-exposed, and...
Authors
Lizabeth Bowen, Susan Knowles, Kathi Lefebvre, Michelle St Martin, Michael Murray, Kimberly A. Kloecker, Daniel Monson, Ben Weitzman, Brenda Ballachey, Heather Coletti, Shannon C. Waters-Dynes, C Cummings
By
Ecosystems Mission Area, Alaska Science Center, National Wildlife Health Center, Western Ecological Research Center (WERC)

Characterizing the oral and distal gut microbiota of the threatened southern sea otter (Enhydra lutris nereis) to enhance conservation practice Characterizing the oral and distal gut microbiota of the threatened southern sea otter (Enhydra lutris nereis) to enhance conservation practice

The southern sea otter (Enhydra lutris nereis) is a threatened sub-species in coastal ecosystems. To understand better the role of diet, monitor health, and enhance management of this and other marine mammal species, we characterized the oral (gingival) and distal gut (rectal and fecal) microbiota of 158 wild southern sea otters living off the coast of central California, USA, and 12...
Authors
Natasha K Dudek, Alexandra D Switzer, Elizabeth K Costello, Michael J. Murray, Joseph A. Tomoleoni, Michelle M. Staedler, M. Tim Tinker, David A Relman
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

New insights into dietary management of polar bears (Ursus maritimus) and brown bears (U. arctos) New insights into dietary management of polar bears (Ursus maritimus) and brown bears (U. arctos)

Although polar bears (Ursus maritimus) and brown bears (U. arctos) have been exhibited in zoological gardens for centuries, little is known about their nutritional needs. Multiple recent studies on both wild and captive polar bears and brown bears have found that they voluntarily select dietary macronutrient proportions resulting in much lower dietary protein and higher fat or digestible
Authors
Charles T. Robbins, Troy N Tollefson, Karyn D. Rode, Joy Erlenbach, Amanda J. Ardente
By
Ecosystems Mission Area, Alaska Science Center

An integrated population model for southern sea otters An integrated population model for southern sea otters

Southern sea otters (Enhydra lutris nereis) have recovered slowly from their near extinction a century ago, and their continued recovery has been challenged by multiple natural and anthropogenic factors. Development of an integrated population model (IPM) for southern sea otters has been identified as a management priority, to help in evaluating the relative impacts of known threats and...
Authors
M. Tim Tinker, Lilian P. Carswell, Joseph A. Tomoleoni, Brian B. Hatfield, Michael D. Harris, Melissa A. Miller, Megan E. Moriarty, Christine K. Johnson, Colleen Young, Laird A. Henkel, Michelle M. Staedler, A. Keith Miles, Julie L. Yee
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

We are developing advanced tools for disease diagnosis, surveillance, risk assessment and control to support management of wildlife diseases.

Marine Mammal Disease Research

Sea otter Elkhorn Slough National Estuarine Research Reserve (WERC)

Population Biology and Behavior of Sea Otters

WERC's sea otter researchers are developing and utilizing a variety of methodological and analytical tools to understand the causes of biological and ecological trends in sea otter populations, and to predict the ecological consequences of management practices on these populations and their ecosystems.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Species Management Research Program, Western Ecological Research Center (WERC)
Population Biology and Behavior of Sea Otters

Population Biology and Behavior of Sea Otters

WERC's sea otter researchers are developing and utilizing a variety of methodological and analytical tools to understand the causes of biological and ecological trends in sea otter populations, and to predict the ecological consequences of management practices on these populations and their ecosystems.
Learn More
WERC Sea otter research in Big Sur, California

California Sea Otter Stranding Network

The California Sea Otter Stranding Network is part of the USGS effort to monitor southern sea otters (Enhydra lutris nereis) and provide data to the U.S. Fish and Wildlife Service. WERC's sea otter team works with multiple institutions and partners to report, recover, and examine stranded sea otters. In addition, instructions on how to report a stranded sea otter are included in this webpage.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Species Management Research Program, Western Ecological Research Center (WERC)
California Sea Otter Stranding Network

California Sea Otter Stranding Network

The California Sea Otter Stranding Network is part of the USGS effort to monitor southern sea otters (Enhydra lutris nereis) and provide data to the U.S. Fish and Wildlife Service. WERC's sea otter team works with multiple institutions and partners to report, recover, and examine stranded sea otters. In addition, instructions on how to report a stranded sea otter are included in this webpage.
Learn More

Explore our science using the data below.

Sea Otter Survey Data, Carcass Recovery Data, and Blood Chemistry Data from Southwest Alaska Sea 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...
By
Western Ecological Research Center (WERC)

Necropsy reference number and summary collection information for Washington state population of northern sea otters examined during 1989-2010 Necropsy reference number and summary collection information for Washington state population of northern sea otters examined during 1989-2010

Morbillivirus epidemics in marine mammals first gained prominence in 1988 when an outbreak of phocine distemper virus (PDV) occurred in European harbor seals (Phoca vitulina vitulina). Prior to 2001, all serosurveys for morbilliviruses in sea otters (Enhydra lutris) in California, Washington and Alaska documented a 0% seroprevalence. The first published serodetections of morbillivirus in...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center

Explore our science using the publications below.

Tool use increases mechanical foraging success and tooth health in southern sea otters (Enhydra lutris nereis) Tool use increases mechanical foraging success and tooth health in southern sea otters (Enhydra lutris nereis)

Although tool use may enhance resource utilization, its fitness benefits are difficult to measure. By examining longitudinal data from 196 radio-tagged southern sea otters (Enhydra lutris nereis), we found that tool-using individuals, particularly females, gained access to larger and/or harder-shelled prey. These mechanical advantages translated to reduced tooth damage during food...
Authors
Chris J. Law, M. Tim Tinker, Jessica A. Fujii, Teri Nicholson, Michelle M. Staedler, Joseph A. Tomoleoni, Colleen Young, Rita S. Mehta
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

Gene expression and wildlife health: Varied interpretations based on perspective Gene 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...
Authors
Lizabeth Bowen, Julie L. Yee, James L. Bodkin, Shannon C. Waters-Dynes, Michael J. Murray, Heather Coletti, Brenda E. Ballachey, Daniel Monson, A. Keith Miles
By
Ecosystems Mission Area, Alaska Science Center, Western Ecological Research Center (WERC)

Divergent gene expression profiles in Alaskan sea otters: An indicator of chronic domoic acid exposure? Divergent gene expression profiles in Alaskan sea otters: An indicator of chronic domoic acid exposure?

An opportunistic investigation into ecosystem instability in Kachemak Bay (KBay), Alaska, has led us to investigate exposure to toxic algae in sea otters. We used gene expression to explore the physiological health of sea otters sampled in KBay in May 2019. We found altered levels of gene transcripts in comparison with reference sea otters from clinically normal, oil-exposed, and...
Authors
Lizabeth Bowen, Susan Knowles, Kathi Lefebvre, Michelle St Martin, Michael Murray, Kimberly A. Kloecker, Daniel Monson, Ben Weitzman, Brenda Ballachey, Heather Coletti, Shannon C. Waters-Dynes, C Cummings
By
Ecosystems Mission Area, Alaska Science Center, National Wildlife Health Center, Western Ecological Research Center (WERC)

Characterizing the oral and distal gut microbiota of the threatened southern sea otter (Enhydra lutris nereis) to enhance conservation practice Characterizing the oral and distal gut microbiota of the threatened southern sea otter (Enhydra lutris nereis) to enhance conservation practice

The southern sea otter (Enhydra lutris nereis) is a threatened sub-species in coastal ecosystems. To understand better the role of diet, monitor health, and enhance management of this and other marine mammal species, we characterized the oral (gingival) and distal gut (rectal and fecal) microbiota of 158 wild southern sea otters living off the coast of central California, USA, and 12...
Authors
Natasha K Dudek, Alexandra D Switzer, Elizabeth K Costello, Michael J. Murray, Joseph A. Tomoleoni, Michelle M. Staedler, M. Tim Tinker, David A Relman
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)

New insights into dietary management of polar bears (Ursus maritimus) and brown bears (U. arctos) New insights into dietary management of polar bears (Ursus maritimus) and brown bears (U. arctos)

Although polar bears (Ursus maritimus) and brown bears (U. arctos) have been exhibited in zoological gardens for centuries, little is known about their nutritional needs. Multiple recent studies on both wild and captive polar bears and brown bears have found that they voluntarily select dietary macronutrient proportions resulting in much lower dietary protein and higher fat or digestible
Authors
Charles T. Robbins, Troy N Tollefson, Karyn D. Rode, Joy Erlenbach, Amanda J. Ardente
By
Ecosystems Mission Area, Alaska Science Center

An integrated population model for southern sea otters An integrated population model for southern sea otters

Southern sea otters (Enhydra lutris nereis) have recovered slowly from their near extinction a century ago, and their continued recovery has been challenged by multiple natural and anthropogenic factors. Development of an integrated population model (IPM) for southern sea otters has been identified as a management priority, to help in evaluating the relative impacts of known threats and...
Authors
M. Tim Tinker, Lilian P. Carswell, Joseph A. Tomoleoni, Brian B. Hatfield, Michael D. Harris, Melissa A. Miller, Megan E. Moriarty, Christine K. Johnson, Colleen Young, Laird A. Henkel, Michelle M. Staedler, A. Keith Miles, Julie L. Yee
By
Ecosystems Mission Area, Western Ecological Research Center (WERC)
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