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George G Esslinger

Using new technologies to study ecosystems; sea otter ecology; geographic information systems; population estimation; predator/prey interactions.

Professional Experience

  • 1998 - Present    Zoologist, USGS, Alaska Biological Science Center Anchorage, Alaska

  • 1995 - 1998         Fish and Wildlife Biologist, USGS, Alaska Biological Science Center Anchorage, Alaska

  • 1993 - 1995         Biological Science Technician, U.S. Fish & Wildlife Service, Alaska Fish & Wildlife Research Center Anchorage, Alaska

  • 1989 - 1993         Biological Science Technician, U.S. Fish & Wildlife Service, Migratory Bird Management Anchorage, Alaska

Education and Certifications

  • M.S.   2011    University of Alaska, Anchorage, AK      Biological Sciences

  • B.S.    1993    Humboldt State University Arcata, CA    Wildlife

Science and Products

link
USGS

SeeOtter: Improving software for AI-assisted processing of imagery for wildlife surveys

Expanding documentation, accessibility, and flexibility of a powerful AI tool for wildlife aerial photo-survey processing
By
Community for Data Integration (CDI)
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SeeOtter: Improving software for AI-assisted processing of imagery for wildlife surveys

Expanding documentation, accessibility, and flexibility of a powerful AI tool for wildlife aerial photo-survey processing
Learn More
link
A juvenile female sea otter eating small green urchins in the intertidal. Glacier Bay near Geikie Inlet, Alaska

Nearshore Marine Ecosystem Research

Nearshore ecosystems include many resources that are of high ecological, recreational, subsistence, and economic value. They also are subject to influences from a wide variety of natural and human-caused perturbations, which can originate in terrestrial or oceanic environments. Our research is designed to evaluate sources of variation in the nearshore and how they influence resources of high...
By
Ecosystems Mission Area, Species Management Research Program, Alaska Science Center
link

Nearshore Marine Ecosystem Research

Nearshore ecosystems include many resources that are of high ecological, recreational, subsistence, and economic value. They also are subject to influences from a wide variety of natural and human-caused perturbations, which can originate in terrestrial or oceanic environments. Our research is designed to evaluate sources of variation in the nearshore and how they influence resources of high...
Learn More
link
A view of the R/V Alaskan Gyre with a glacier in the background in Harriman Fjord in Prince William Sound, Alaska

USGS Research Vessel Alaskan Gyre

The R/V Alaskan Gyre is a 50-foot fiberglass seiner that has been converted into a versatile research vessel to provide USGS scientists and collaborators with access to remote marine areas of Alaska and serve as a mobile laboratory. The vessel was built by Ledford Marine of Marysville, Washington in 1989 and is named after the Alaskan Gyre, a series of wind driven currents that rotate counter...
By
Alaska Science Center
link

USGS Research Vessel Alaskan Gyre

The R/V Alaskan Gyre is a 50-foot fiberglass seiner that has been converted into a versatile research vessel to provide USGS scientists and collaborators with access to remote marine areas of Alaska and serve as a mobile laboratory. The vessel was built by Ledford Marine of Marysville, Washington in 1989 and is named after the Alaskan Gyre, a series of wind driven currents that rotate counter...
Learn More
Filter Total Items: 16

Sea Otter Aerial Survey Data from lower Cook Inlet and the outer Kenai Penisula, Alaska, 2002

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in lower Cook Inlet and the outer Kenai Peninsula, Alaska, based on data collected during a series of aerial surveys from May-Aug 2002. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transect
By
Alaska Science Center

Sea Otter Aerial Survey Data from Western Prince William Sound, Alaska, 2022

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in western Prince William Sound, Alaska, based on data collected during a series of population-wide aerial surveys in June 2022. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transects, and
By
Alaska Science Center

Glacier Bay National Park and Preserve Sea Otter Forage Data, 1993-2019

These data describe observations of sea otter foraging behavior in Glacier Bay National Park and Preserve. Data consist of dive and surface times, success in prey retrieval, prey item, prey quantity, and size. Additionally, location of observations, and age class, sex, and pup status of the focal sea otter were also recorded.
By
Alaska Science Center

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 downloaded
By
Alaska Science Center

Intertidal 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 mi
By
Alaska Science Center

Intertidal and Subtidal Sea Otter Prey Sampling in Mixed Sediment Habitat in Glacier Bay National Park and Preserve, Alaska, 1998 to 2011

This dataset provides clam species abundance and size data from intertidal and subtidal mixed sediment habitats in Glacier Bay National Park and Preserve (GBNPP). Data are provided for all observed clams, horse mussels, or urchins 14 mm or larger. Sampling involved excavating 25 cm of substrate from quadrats (approximately 0.25 sq meter) along transects at random and selected sites, 10 quadrats at
By
Alaska Science Center

Sea Otter Aerial Survey Data from Lower Cook Inlet, Alaska, 2017

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in lower Cook Inlet, Alaska, based on data collected during a series of population-wide aerial surveys in May 2017. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transects, and (3) Transect
By
Alaska Science Center

Sea Otter Aerial Survey Data from Western Prince William Sound, Alaska, 2017

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in western Prince William Sound, Alaska, based on data collected during a series of population-wide aerial surveys in June 2017. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transects, and
By
Alaska Science Center

Sea Otter Aerial Survey Data from the outer Kenai Peninsula, Alaska, 2019

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) near the outer Kenai Peninsula, Alaska, based on data collected during a series of population-wide aerial surveys in June 2019. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transects, and (
By
Alaska Science Center

Sea Otter Aerial Survey Data from Northern and Eastern Prince William Sound, Alaska, 2014

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in northern and eastern Prince William Sound, Alaska, based on data collected during a series of population-wide aerial surveys in June 2014. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the tr
By
Alaska Science Center

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 per-capita a
By
Western Ecological Research Center (WERC)

Morphometric and Reproductive Status Data for Sea Otters Collected or Captured in Alaska

This dataset includes morphometric measurements and pregnancy / dependency status from sea otters captured or collected (experimental harvests or recovered after the Exxon Valdez Oil Spill) in Alaska, 1947-2019 by the U.S. Geological Survey (USGS) and the U.S. Fish and Wildlife Service (USFWS). Data collected include total body length, tail length, body mass, axillary girth, paw width, canine diam
By
Alaska Science Center
Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.
Distribution map of sea otters in southcentral Alaska
Distribution map of sea otters in southcentral Alaska
Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

Distribution map of sea otters in southcentral Alaska

Distribution map of sea otters in southcentral Alaska

Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

By
Alaska Science Center, Alaska Science Center
Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

Distribution map of sea otters in southcentral Alaska

Distribution map of sea otters in southcentral Alaska

Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

By
Alaska Science Center, Alaska Science Center
Figure of density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.
Density estimate of sea otters in southcentral Alaska
Density estimate of sea otters in southcentral Alaska
Figure of density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

Density estimate of sea otters in southcentral Alaska

Density estimate of sea otters in southcentral Alaska

Density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019. Sea otters in southcentral Alaska are the northernmost stock of sea otters and a keystone predator because they are known for structuring nearshore marine ecosystems through their feeding habits.  Biologists with the USGS and USFWS conducted aerial

By
Alaska Science Center, Alaska Science Center
Figure of density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

Density estimate of sea otters in southcentral Alaska

Density estimate of sea otters in southcentral Alaska

Density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019. Sea otters in southcentral Alaska are the northernmost stock of sea otters and a keystone predator because they are known for structuring nearshore marine ecosystems through their feeding habits.  Biologists with the USGS and USFWS conducted aerial

By
Alaska Science Center, Alaska Science Center
A layout diagram of the R/V Alaskan Gyre
A layout diagram of the R/V Alaskan Gyre
A layout diagram of the R/V Alaskan Gyre
A layout diagram of the R/V Alaskan Gyre

A layout diagram of the R/V Alaskan Gyre

A layout diagram of the R/V Alaskan Gyre

A layout illustration of the R/V Alaskan Gyre deck.

By
Alaska Science Center
A layout diagram of the R/V Alaskan Gyre

A layout diagram of the R/V Alaskan Gyre

A layout diagram of the R/V Alaskan Gyre

A layout illustration of the R/V Alaskan Gyre deck.

By
Alaska Science Center
The R/V Alaskan Gyre in Katmai National Park, Alaska
A view of the R/V Alaskan Gyre in Katmai National Park, Alaska
A view of the R/V Alaskan Gyre in Katmai National Park, Alaska
The R/V Alaskan Gyre in Katmai National Park, Alaska

A view of the R/V Alaskan Gyre in Katmai National Park, Alaska

A view of the R/V Alaskan Gyre in Katmai National Park, Alaska

The  R/V Alaskan Gyre in Katmai National Park, Alaska

By
Alaska Science Center
The R/V Alaskan Gyre in Katmai National Park, Alaska

A view of the R/V Alaskan Gyre in Katmai National Park, Alaska

A view of the R/V Alaskan Gyre in Katmai National Park, Alaska

The  R/V Alaskan Gyre in Katmai National Park, Alaska

By
Alaska Science Center
Filter Total Items: 36

The dynamics of sea otter prey selection under population growth and expansion

Sea otters (Enhydra lutris) were extirpated from much of their range in the North Pacific by the early 1900s but have made a remarkable recovery in Southeast Alaska. Sea otter populations have been particularly successful in Glacier Bay, Alaska, a protected tidewater glacier fjord with a diverse and productive nearshore habitat. Collection of sea otter foraging observations in Glacier Bay began in
Authors
Clint Leach, Ben Weitzman, Jim Bodkin, Daniel Esler, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Jamie N. Womble, Mevin B. Hooten
By
Alaska Science Center

Understanding sea otter population change in southeast Alaska

IntroductionThe Southeast Alaska (SE) stock of northern sea otters (Enhydra lutris kenyoni) ranges from Cape Yakataga on the north to the Dixon Entrance on the south. During the maritime fur trade, sea otters were commercially harvested to near extinction in SE for their pelts and were presumed unlikely to naturally repopulate the region.
Authors
Joseph Michael Eisaguirre, Toshio D. Matsuoka, George G. Esslinger, Benjamin P Weitzman, Paul A. Schuette, Jamie N. Womble
By
Alaska Science Center

Informing management of recovering predators and their prey with ecological diffusion models

The reintroduction and recovery of predators can be ecologically beneficial as well as socially and economically controversial. However, the growth and expansion of predator populations, and thus their ecological, social, and economic impacts, are not static but rather they vary in space and time. We propose a spatiotemporal statistical modeling framework based on ecological diffusion to better in
Authors
Joseph Michael Eisaguirre, Perry J. Williams, Xinyi Lu, Michelle L. Kissling, Paul A Schutte, Benjamin P Weitzman, William S. Beatty, George G. Esslinger, Jamie N. Womble, Mevin B. Hooten
By
Alaska Science Center

Nearshore ecosystems in the Gulf of Alaska

Nearshore ecosystem monitoring in western Prince William Sound, Kenai Fjords National Park, Kachemak Bay, and Katmai National Park and Preserve has been conducted as a single Nearshore Component of the Gulf Watch Alaska program over the past five years (2017-2021). This program builds on the previous five years and continues, in many cases, decades of preceding research and monitoring. During the
Authors
Heather A. Coletti, Daniel Esler, Brenda Ballachey, Jim Bodkin, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Brian H. Robinson, Sarah Beth Traiger, Katrin Iken, Brenda Konar, Tom Dean, Mandy Lindeberg, Ben Weitzman
By
Alaska Science Center

Revealing 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 monitoring
Authors
Clinton B. Leach, Benjamin P. Weitzman, James L. Bodkin, Daniel Esler, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Jamie N. Womble, Mevin B. Hooten
By
Alaska Science Center

Northern Sea Otter (Enhydra lutris kenyoni) population abundance and distribution across the southeast Alaska stock, summer 2022

In the summer of 2022, the U.S. Fish & Wildlife Service and partners successfully completed the first single-year, aerial photo survey of sea otters across the entire Southeast stock of northern sea otters. This document presents the latest findings from the 2022 Southeast Alaska Sea Otter Survey, providing up-to-date information regarding occupancy, abundance and carrying capacity. We collected t
Authors
Paul Schuette, Joseph Michael Eisaguirre, Benjamin P Weitzman, Collin Power, Evan Wetherington, Jenipher Cate, Jamie N. Womble, Linnea Pearson, Daniel Melody, Chelsea Merriman, Kat Hanks, George G. Esslinger
By
Alaska Science Center

Where 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 mar
Authors
Heather Coletti, Grant Hilderbrand, James L. Bodkin, Brenda E. Ballachey, Joy Erlenbach, George G. Esslinger, Michael P. Hannam, Kimberly A. Kloecker, Buck Mangipane, Amy Miller, Daniel Monson, Benjamin Pister, K. Griffin, K. Bodkin, Tom Smith
By
Ecosystems Mission Area, Alaska Science Center

Abundance and distribution of sea otters (Enhydra lutris) in the southcentral Alaska stock, 2014, 2017, and 2019

The Southcentral Alaska (SCAK) sea otter (Enhydra lutris) stock is the northernmost stock of sea otters, a keystone predator known for structuring nearshore marine ecosystems. We conducted aerial surveys within the range of the SCAK sea otter stock to provide recent estimates of sea otter abundance and distribution. We defined three survey regions: (1) Eastern Cook Inlet (2017), (2) Outer Kenai Pe
Authors
George G. Esslinger, Brian H. Robinson, Daniel H. Monson, Rebecca L. Taylor, Daniel Esler, Ben P. Weitzman, Joel Garlich-Miller
By
Ecosystems Mission Area, Alaska Science Center

Diffusion modeling reveals effects of multiple release sites and human activity on a recolonizing apex predator

BackgroundReintroducing predators is a promising conservation tool to help remedy human-caused ecosystem changes. However, the growth and spread of a reintroduced population is a spatiotemporal process that is driven by a suite of factors, such as habitat change, human activity, and prey availability. Sea otters (Enhydra lutris) are apex predators of nearshore marine ecosystems that had declined n
Authors
Joseph M. Eisaguirre, Perry J. Willliams, Xinyi Lu, Michelle L. Kissling, William S. Beatty, George G. Esslinger, Jamie N. Womble, Mevin Hooten
By
Ecosystems Mission Area, Alaska Science Center, Fort Collins Science Center

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

Authors
M. 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. Estes
By
Ecosystems Mission Area, Alaska Science Center, Western Ecological Research Center (WERC)

Trends 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 compile
Authors
M. Tim Tinker, Verena A. Gill, George G. Esslinger, James L. Bodkin, Melissa Monk, Marc Mangel, Daniel Monson, Wendel W. Raymond, Michelle Kissling
By
Ecosystems Mission Area, Alaska Science Center

The rise of an apex predator following deglaciation

AimSea otters (Enhydra lutris) are an apex predator of the nearshore marine community and nearly went extinct at the turn of the 20th century. Reintroductions and legal protection allowed sea otters to re‐colonize much of their former range. Our objective was to chronicle the colonization of this apex predator in Glacier Bay, Alaska, to help understand the mechanisms that governed their successful
Authors
Mevin Hooten, George G. Esslinger
By
Ecosystems Mission Area, Water Resources Mission Area, Cooperative Research Units, Alaska Science Center, Fort Collins Science Center

Science and Products

link
USGS

SeeOtter: Improving software for AI-assisted processing of imagery for wildlife surveys

Expanding documentation, accessibility, and flexibility of a powerful AI tool for wildlife aerial photo-survey processing
By
Community for Data Integration (CDI)
link

SeeOtter: Improving software for AI-assisted processing of imagery for wildlife surveys

Expanding documentation, accessibility, and flexibility of a powerful AI tool for wildlife aerial photo-survey processing
Learn More
link
A juvenile female sea otter eating small green urchins in the intertidal. Glacier Bay near Geikie Inlet, Alaska

Nearshore Marine Ecosystem Research

Nearshore ecosystems include many resources that are of high ecological, recreational, subsistence, and economic value. They also are subject to influences from a wide variety of natural and human-caused perturbations, which can originate in terrestrial or oceanic environments. Our research is designed to evaluate sources of variation in the nearshore and how they influence resources of high...
By
Ecosystems Mission Area, Species Management Research Program, Alaska Science Center
link

Nearshore Marine Ecosystem Research

Nearshore ecosystems include many resources that are of high ecological, recreational, subsistence, and economic value. They also are subject to influences from a wide variety of natural and human-caused perturbations, which can originate in terrestrial or oceanic environments. Our research is designed to evaluate sources of variation in the nearshore and how they influence resources of high...
Learn More
link
A view of the R/V Alaskan Gyre with a glacier in the background in Harriman Fjord in Prince William Sound, Alaska

USGS Research Vessel Alaskan Gyre

The R/V Alaskan Gyre is a 50-foot fiberglass seiner that has been converted into a versatile research vessel to provide USGS scientists and collaborators with access to remote marine areas of Alaska and serve as a mobile laboratory. The vessel was built by Ledford Marine of Marysville, Washington in 1989 and is named after the Alaskan Gyre, a series of wind driven currents that rotate counter...
By
Alaska Science Center
link

USGS Research Vessel Alaskan Gyre

The R/V Alaskan Gyre is a 50-foot fiberglass seiner that has been converted into a versatile research vessel to provide USGS scientists and collaborators with access to remote marine areas of Alaska and serve as a mobile laboratory. The vessel was built by Ledford Marine of Marysville, Washington in 1989 and is named after the Alaskan Gyre, a series of wind driven currents that rotate counter...
Learn More
Filter Total Items: 16

Sea Otter Aerial Survey Data from lower Cook Inlet and the outer Kenai Penisula, Alaska, 2002

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in lower Cook Inlet and the outer Kenai Peninsula, Alaska, based on data collected during a series of aerial surveys from May-Aug 2002. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transect
By
Alaska Science Center

Sea Otter Aerial Survey Data from Western Prince William Sound, Alaska, 2022

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in western Prince William Sound, Alaska, based on data collected during a series of population-wide aerial surveys in June 2022. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transects, and
By
Alaska Science Center

Glacier Bay National Park and Preserve Sea Otter Forage Data, 1993-2019

These data describe observations of sea otter foraging behavior in Glacier Bay National Park and Preserve. Data consist of dive and surface times, success in prey retrieval, prey item, prey quantity, and size. Additionally, location of observations, and age class, sex, and pup status of the focal sea otter were also recorded.
By
Alaska Science Center

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 downloaded
By
Alaska Science Center

Intertidal 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 mi
By
Alaska Science Center

Intertidal and Subtidal Sea Otter Prey Sampling in Mixed Sediment Habitat in Glacier Bay National Park and Preserve, Alaska, 1998 to 2011

This dataset provides clam species abundance and size data from intertidal and subtidal mixed sediment habitats in Glacier Bay National Park and Preserve (GBNPP). Data are provided for all observed clams, horse mussels, or urchins 14 mm or larger. Sampling involved excavating 25 cm of substrate from quadrats (approximately 0.25 sq meter) along transects at random and selected sites, 10 quadrats at
By
Alaska Science Center

Sea Otter Aerial Survey Data from Lower Cook Inlet, Alaska, 2017

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in lower Cook Inlet, Alaska, based on data collected during a series of population-wide aerial surveys in May 2017. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transects, and (3) Transect
By
Alaska Science Center

Sea Otter Aerial Survey Data from Western Prince William Sound, Alaska, 2017

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in western Prince William Sound, Alaska, based on data collected during a series of population-wide aerial surveys in June 2017. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transects, and
By
Alaska Science Center

Sea Otter Aerial Survey Data from the outer Kenai Peninsula, Alaska, 2019

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) near the outer Kenai Peninsula, Alaska, based on data collected during a series of population-wide aerial surveys in June 2019. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the transects, and (
By
Alaska Science Center

Sea Otter Aerial Survey Data from Northern and Eastern Prince William Sound, Alaska, 2014

This dataset consists of three tables related to abundance and distribution of northern sea otters (Enhydra lutris kenyoni) in northern and eastern Prince William Sound, Alaska, based on data collected during a series of population-wide aerial surveys in June 2014. The dataset consists of: (1) sea otter counts along strip transects, (2) sea otter counts in Intensive Search Unit (ISU) within the tr
By
Alaska Science Center

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 per-capita a
By
Western Ecological Research Center (WERC)

Morphometric and Reproductive Status Data for Sea Otters Collected or Captured in Alaska

This dataset includes morphometric measurements and pregnancy / dependency status from sea otters captured or collected (experimental harvests or recovered after the Exxon Valdez Oil Spill) in Alaska, 1947-2019 by the U.S. Geological Survey (USGS) and the U.S. Fish and Wildlife Service (USFWS). Data collected include total body length, tail length, body mass, axillary girth, paw width, canine diam
By
Alaska Science Center
Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.
Distribution map of sea otters in southcentral Alaska
Distribution map of sea otters in southcentral Alaska
Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

Distribution map of sea otters in southcentral Alaska

Distribution map of sea otters in southcentral Alaska

Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

By
Alaska Science Center, Alaska Science Center
Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

Distribution map of sea otters in southcentral Alaska

Distribution map of sea otters in southcentral Alaska

Distribution map of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

By
Alaska Science Center, Alaska Science Center
Figure of density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.
Density estimate of sea otters in southcentral Alaska
Density estimate of sea otters in southcentral Alaska
Figure of density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

Density estimate of sea otters in southcentral Alaska

Density estimate of sea otters in southcentral Alaska

Density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019. Sea otters in southcentral Alaska are the northernmost stock of sea otters and a keystone predator because they are known for structuring nearshore marine ecosystems through their feeding habits.  Biologists with the USGS and USFWS conducted aerial

By
Alaska Science Center, Alaska Science Center
Figure of density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019.

Density estimate of sea otters in southcentral Alaska

Density estimate of sea otters in southcentral Alaska

Density estimate of sea otters in southcentral Alaska from aerial surveys flown in 2014, 2017, and 2019. Sea otters in southcentral Alaska are the northernmost stock of sea otters and a keystone predator because they are known for structuring nearshore marine ecosystems through their feeding habits.  Biologists with the USGS and USFWS conducted aerial

By
Alaska Science Center, Alaska Science Center
A layout diagram of the R/V Alaskan Gyre
A layout diagram of the R/V Alaskan Gyre
A layout diagram of the R/V Alaskan Gyre
A layout diagram of the R/V Alaskan Gyre

A layout diagram of the R/V Alaskan Gyre

A layout diagram of the R/V Alaskan Gyre

A layout illustration of the R/V Alaskan Gyre deck.

By
Alaska Science Center
A layout diagram of the R/V Alaskan Gyre

A layout diagram of the R/V Alaskan Gyre

A layout diagram of the R/V Alaskan Gyre

A layout illustration of the R/V Alaskan Gyre deck.

By
Alaska Science Center
The R/V Alaskan Gyre in Katmai National Park, Alaska
A view of the R/V Alaskan Gyre in Katmai National Park, Alaska
A view of the R/V Alaskan Gyre in Katmai National Park, Alaska
The R/V Alaskan Gyre in Katmai National Park, Alaska

A view of the R/V Alaskan Gyre in Katmai National Park, Alaska

A view of the R/V Alaskan Gyre in Katmai National Park, Alaska

The  R/V Alaskan Gyre in Katmai National Park, Alaska

By
Alaska Science Center
The R/V Alaskan Gyre in Katmai National Park, Alaska

A view of the R/V Alaskan Gyre in Katmai National Park, Alaska

A view of the R/V Alaskan Gyre in Katmai National Park, Alaska

The  R/V Alaskan Gyre in Katmai National Park, Alaska

By
Alaska Science Center
Filter Total Items: 36

The dynamics of sea otter prey selection under population growth and expansion

Sea otters (Enhydra lutris) were extirpated from much of their range in the North Pacific by the early 1900s but have made a remarkable recovery in Southeast Alaska. Sea otter populations have been particularly successful in Glacier Bay, Alaska, a protected tidewater glacier fjord with a diverse and productive nearshore habitat. Collection of sea otter foraging observations in Glacier Bay began in
Authors
Clint Leach, Ben Weitzman, Jim Bodkin, Daniel Esler, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Jamie N. Womble, Mevin B. Hooten
By
Alaska Science Center

Understanding sea otter population change in southeast Alaska

IntroductionThe Southeast Alaska (SE) stock of northern sea otters (Enhydra lutris kenyoni) ranges from Cape Yakataga on the north to the Dixon Entrance on the south. During the maritime fur trade, sea otters were commercially harvested to near extinction in SE for their pelts and were presumed unlikely to naturally repopulate the region.
Authors
Joseph Michael Eisaguirre, Toshio D. Matsuoka, George G. Esslinger, Benjamin P Weitzman, Paul A. Schuette, Jamie N. Womble
By
Alaska Science Center

Informing management of recovering predators and their prey with ecological diffusion models

The reintroduction and recovery of predators can be ecologically beneficial as well as socially and economically controversial. However, the growth and expansion of predator populations, and thus their ecological, social, and economic impacts, are not static but rather they vary in space and time. We propose a spatiotemporal statistical modeling framework based on ecological diffusion to better in
Authors
Joseph Michael Eisaguirre, Perry J. Williams, Xinyi Lu, Michelle L. Kissling, Paul A Schutte, Benjamin P Weitzman, William S. Beatty, George G. Esslinger, Jamie N. Womble, Mevin B. Hooten
By
Alaska Science Center

Nearshore ecosystems in the Gulf of Alaska

Nearshore ecosystem monitoring in western Prince William Sound, Kenai Fjords National Park, Kachemak Bay, and Katmai National Park and Preserve has been conducted as a single Nearshore Component of the Gulf Watch Alaska program over the past five years (2017-2021). This program builds on the previous five years and continues, in many cases, decades of preceding research and monitoring. During the
Authors
Heather A. Coletti, Daniel Esler, Brenda Ballachey, Jim Bodkin, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Brian H. Robinson, Sarah Beth Traiger, Katrin Iken, Brenda Konar, Tom Dean, Mandy Lindeberg, Ben Weitzman
By
Alaska Science Center

Revealing 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 monitoring
Authors
Clinton B. Leach, Benjamin P. Weitzman, James L. Bodkin, Daniel Esler, George G. Esslinger, Kimberly A. Kloecker, Daniel Monson, Jamie N. Womble, Mevin B. Hooten
By
Alaska Science Center

Northern Sea Otter (Enhydra lutris kenyoni) population abundance and distribution across the southeast Alaska stock, summer 2022

In the summer of 2022, the U.S. Fish & Wildlife Service and partners successfully completed the first single-year, aerial photo survey of sea otters across the entire Southeast stock of northern sea otters. This document presents the latest findings from the 2022 Southeast Alaska Sea Otter Survey, providing up-to-date information regarding occupancy, abundance and carrying capacity. We collected t
Authors
Paul Schuette, Joseph Michael Eisaguirre, Benjamin P Weitzman, Collin Power, Evan Wetherington, Jenipher Cate, Jamie N. Womble, Linnea Pearson, Daniel Melody, Chelsea Merriman, Kat Hanks, George G. Esslinger
By
Alaska Science Center

Where 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 mar
Authors
Heather Coletti, Grant Hilderbrand, James L. Bodkin, Brenda E. Ballachey, Joy Erlenbach, George G. Esslinger, Michael P. Hannam, Kimberly A. Kloecker, Buck Mangipane, Amy Miller, Daniel Monson, Benjamin Pister, K. Griffin, K. Bodkin, Tom Smith
By
Ecosystems Mission Area, Alaska Science Center

Abundance and distribution of sea otters (Enhydra lutris) in the southcentral Alaska stock, 2014, 2017, and 2019

The Southcentral Alaska (SCAK) sea otter (Enhydra lutris) stock is the northernmost stock of sea otters, a keystone predator known for structuring nearshore marine ecosystems. We conducted aerial surveys within the range of the SCAK sea otter stock to provide recent estimates of sea otter abundance and distribution. We defined three survey regions: (1) Eastern Cook Inlet (2017), (2) Outer Kenai Pe
Authors
George G. Esslinger, Brian H. Robinson, Daniel H. Monson, Rebecca L. Taylor, Daniel Esler, Ben P. Weitzman, Joel Garlich-Miller
By
Ecosystems Mission Area, Alaska Science Center

Diffusion modeling reveals effects of multiple release sites and human activity on a recolonizing apex predator

BackgroundReintroducing predators is a promising conservation tool to help remedy human-caused ecosystem changes. However, the growth and spread of a reintroduced population is a spatiotemporal process that is driven by a suite of factors, such as habitat change, human activity, and prey availability. Sea otters (Enhydra lutris) are apex predators of nearshore marine ecosystems that had declined n
Authors
Joseph M. Eisaguirre, Perry J. Willliams, Xinyi Lu, Michelle L. Kissling, William S. Beatty, George G. Esslinger, Jamie N. Womble, Mevin Hooten
By
Ecosystems Mission Area, Alaska Science Center, Fort Collins Science Center

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

Authors
M. 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. Estes
By
Ecosystems Mission Area, Alaska Science Center, Western Ecological Research Center (WERC)

Trends 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 compile
Authors
M. Tim Tinker, Verena A. Gill, George G. Esslinger, James L. Bodkin, Melissa Monk, Marc Mangel, Daniel Monson, Wendel W. Raymond, Michelle Kissling
By
Ecosystems Mission Area, Alaska Science Center

The rise of an apex predator following deglaciation

AimSea otters (Enhydra lutris) are an apex predator of the nearshore marine community and nearly went extinct at the turn of the 20th century. Reintroductions and legal protection allowed sea otters to re‐colonize much of their former range. Our objective was to chronicle the colonization of this apex predator in Glacier Bay, Alaska, to help understand the mechanisms that governed their successful
Authors
Mevin Hooten, George G. Esslinger
By
Ecosystems Mission Area, Water Resources Mission Area, Cooperative Research Units, Alaska Science Center, Fort Collins Science Center
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