Drones for Science: Walrus Calf Scavenged by Polar Bear
Drones for Science: Walrus Calf Scavenged by Polar BearThis is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
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Applying wildlife biology tools, including satellite imagery interpretation and telemetry, to address Pacific walrus conservation problems.
2022 - Present Research Wildlife Biologist, USGS, Alaska Science Center, Anchorage, Alaska
2004 - 2022 Wildlife Biologist, USGS, Alaska Science Center, Anchorage, Alaska
2003 - 2004 Wildlife Biologist, U.S. Fish and Wildlife Service, Kodiak National Wildlife Refuge, Kodiak, Alaska
1999 - 2003 Wildlife Biologist, USGS, Alaska Biological Science Center, Anchorage, Alaska
1998 - 1999 Wildlife Biologist, Marine Mammals Management, U.S. Fish & Wildlife Service, Anchorage, Alaska
1997 - 1999 (summers) Volunteer Wildlife Biologist, Tongass Bat Habitat Project, U.S. Forest Service, Thorne Bay, Alaska
1995 - 1998 Biological Technician / Walrus Harvest Monitor, Marine Mammals Management, U.S. Fish & Wildlife Service, Anchorage, Alaska
1994 - 1995 Volunteer, Kenai National Wildlife Refuge, U.S. Fish & Wildlife Service, Soldotna, Alaska
M.A. 1994 University of Texas, Austin, TX Ecology
B.S. 1989 University of Wisconsin, Madison, WI Molecular Biology
Reviewer: BioScience, Arctic, Marine Mammal Science, Progress In Oceanography, Polar Biology
Contributor: R-sig-geo
1989-1990 Fulbright Scholar, Bayreuth, Germany
Orange drone with broad wing fit with two propellers and with two flaps at its base on beach. Female walking towards drone.
This is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
This is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
Sounds from a large herd of walruses resting on Alaskan shores of the Chukchi Sea recorded. Deep full barks and calls of individual walruses near the edge of the herd are audible over a continuous rhythmic humming sound that arises from the calls of tens of thousands of walrsues from deeper within the herd.
Sounds from a large herd of walruses resting on Alaskan shores of the Chukchi Sea recorded. Deep full barks and calls of individual walruses near the edge of the herd are audible over a continuous rhythmic humming sound that arises from the calls of tens of thousands of walrsues from deeper within the herd.
USGS uses small uncrewed aerial systems, also known as drones for science, to survey walrus herds and carcasses on remote Alaskan beaches. The USGS visual observer, Christina Ahlstrom, keeps her eyes on the survey drone while the remote pilot prepares it to survey the walrus herd that is visible in the distance behind her on the beach.
USGS uses small uncrewed aerial systems, also known as drones for science, to survey walrus herds and carcasses on remote Alaskan beaches. The USGS visual observer, Christina Ahlstrom, keeps her eyes on the survey drone while the remote pilot prepares it to survey the walrus herd that is visible in the distance behind her on the beach.
Orange drone on beach with several walrus carcasses near shoreline. Close up of dead young walrus on rocky sandy beach.
This is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
This is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
Aerial survey drone prepared for flight positioned on the beach near walrus calf carcasses. When sea ice retreats from large regions of the Chukchi Sea large herds of female and young walruses come to shore to rest.
Aerial survey drone prepared for flight positioned on the beach near walrus calf carcasses. When sea ice retreats from large regions of the Chukchi Sea large herds of female and young walruses come to shore to rest.
USGS is flying drones for science, small uncrewed areal systems (sUAS), to surveys walruses when they rest on shore. The sUAS makes minimal sound due it is broad wing and is flown high above the walrus herds to enables survey data collection with minimal risk to walruses.
USGS is flying drones for science, small uncrewed areal systems (sUAS), to surveys walruses when they rest on shore. The sUAS makes minimal sound due it is broad wing and is flown high above the walrus herds to enables survey data collection with minimal risk to walruses.
Two adult walrus carcasses on the beach observed during the summer after a large group of walruses had rested on shore. USGS is collaborating with the North Slope Borough Department of Wildlife Management to screen walruses for wildlife diseases and algal toxins. The University of Alaska Fairbanks is collaborating with USGS to validate drone survey metho
Two adult walrus carcasses on the beach observed during the summer after a large group of walruses had rested on shore. USGS is collaborating with the North Slope Borough Department of Wildlife Management to screen walruses for wildlife diseases and algal toxins. The University of Alaska Fairbanks is collaborating with USGS to validate drone survey metho
This is a community flyer for distribution in Point Lay, Alaska, to alert community members of USGS activities in the area. A collaborative team of USGS, the North Slope Borough, University of Alaska Fairbanks, and Point Lay residents will assist in surveys of walrus carcasses at a remote coastal haulout that has been used by hundreds of thousands of walruses e
This is a community flyer for distribution in Point Lay, Alaska, to alert community members of USGS activities in the area. A collaborative team of USGS, the North Slope Borough, University of Alaska Fairbanks, and Point Lay residents will assist in surveys of walrus carcasses at a remote coastal haulout that has been used by hundreds of thousands of walruses e
This image shows the estimated outline and area (in square meters) occupied by Pacific walrus at a large coastal haulout in Chukotka Russia in 2023 at Cape Serdtse Kamen. The image is derived from images in 2022 and 2023 from a variety of Earth observing satellite imagery sources collected at known walrus coastal haulouts in Alaska and Chukotka, Russia.
This image shows the estimated outline and area (in square meters) occupied by Pacific walrus at a large coastal haulout in Chukotka Russia in 2023 at Cape Serdtse Kamen. The image is derived from images in 2022 and 2023 from a variety of Earth observing satellite imagery sources collected at known walrus coastal haulouts in Alaska and Chukotka, Russia.
This image shows the estimated area (in square meters) occupied by Pacific walrus at eight coastal haulouts in northern Alaska and Chukotka Russia in 2023 (walrus were detected at two haulouts in 2023: Point Lay, Alaska and Cape Serdtse Kamen, Chukotka).
This image shows the estimated area (in square meters) occupied by Pacific walrus at eight coastal haulouts in northern Alaska and Chukotka Russia in 2023 (walrus were detected at two haulouts in 2023: Point Lay, Alaska and Cape Serdtse Kamen, Chukotka).
Figure showing two Capella Space Synthetic Aperture Radar (SAR) satellite images of a walrus haulout in Russia during and after walrus occupancy. USGS has found that SAR imagery can detect walruses when they rest on shore in large numbers and is pursuing studies to understand how satellite imagery can support improved management of the Pacific walrus.
Figure showing two Capella Space Synthetic Aperture Radar (SAR) satellite images of a walrus haulout in Russia during and after walrus occupancy. USGS has found that SAR imagery can detect walruses when they rest on shore in large numbers and is pursuing studies to understand how satellite imagery can support improved management of the Pacific walrus.
Figure comparing Synthetic Aperture Radar (SAR) satellite images of Pacific walruses on a terrestrial haulout near Point Lay, Alaska, as collected by four different SAR instruments possessing different spatial resolution capabilities (Sentinel-1, Radarsat-2, TerraSAR-X, and Capella Space).
Figure comparing Synthetic Aperture Radar (SAR) satellite images of Pacific walruses on a terrestrial haulout near Point Lay, Alaska, as collected by four different SAR instruments possessing different spatial resolution capabilities (Sentinel-1, Radarsat-2, TerraSAR-X, and Capella Space).
Sea World Orlando marine mammal trainers, Kelly Trotto, Josh Boepple and Matt Oddi, measure a healthy mature female walrus in support of a USGS study that seeks to develop methods to monitor walrus body condition from survey drones flown high above walruses where they rest on shore. With this new tool, USGS intends to examine the environmental factors that affe
Sea World Orlando marine mammal trainers, Kelly Trotto, Josh Boepple and Matt Oddi, measure a healthy mature female walrus in support of a USGS study that seeks to develop methods to monitor walrus body condition from survey drones flown high above walruses where they rest on shore. With this new tool, USGS intends to examine the environmental factors that affe
Indianapolis Zoo marine mammal trainers, Erika Allen and Sydney Pitts, measure a healthy female walrus in support of a USGS study that seeks to develop methods to monitor walrus body condition from survey drones flown high above walruses where they rest on shore. With this new tool, USGS intends to examine the environmental factors that affect walrus body condi
Indianapolis Zoo marine mammal trainers, Erika Allen and Sydney Pitts, measure a healthy female walrus in support of a USGS study that seeks to develop methods to monitor walrus body condition from survey drones flown high above walruses where they rest on shore. With this new tool, USGS intends to examine the environmental factors that affect walrus body condi
This is a graphical abstract for a publication by the USGS that evaluates satellite imagery for monitoring large Pacific walrus haulouts in northwestern Alaska.
This is a graphical abstract for a publication by the USGS that evaluates satellite imagery for monitoring large Pacific walrus haulouts in northwestern Alaska.
Aerial view of a large walrus haulout on the northwestern shores of Alaska. The image was taken using an unoccupied aerial system, commonly referred to as a survey drone. This survey was flown to collect imagery of walruses resting on shore for purposes of estimating the abundance of walruses that use the U.S. Chukchi Sea waters during the autumn.
Aerial view of a large walrus haulout on the northwestern shores of Alaska. The image was taken using an unoccupied aerial system, commonly referred to as a survey drone. This survey was flown to collect imagery of walruses resting on shore for purposes of estimating the abundance of walruses that use the U.S. Chukchi Sea waters during the autumn.
An adult female Pacific walrus resting on the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
An adult female Pacific walrus resting on the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
A young male Pacific walrus resting on the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
A young male Pacific walrus resting on the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
A young male Pacific walrus moving up the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
A young male Pacific walrus moving up the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
Aerial view of walruses crowded tightly on a thin strip of land surrounded by sea water.
When sea ice is absent in the Chukchi Sea region, walruses gather in large numbers along the northwestern coast of Alaska to rest on shore. USGS has worked with local communities and partners across the Bering Strait to develop methods to estimate regional abundance of walruses using these coastal haulouts and to understand the population consequences of resti
When sea ice is absent in the Chukchi Sea region, walruses gather in large numbers along the northwestern coast of Alaska to rest on shore. USGS has worked with local communities and partners across the Bering Strait to develop methods to estimate regional abundance of walruses using these coastal haulouts and to understand the population consequences of resti
Aerial view of the edge of a large walrus herd hauled out on the northwestern shores of Alaska. The image was taken using an unoccupied aerial system, commonly referred to as a survey drone that was flown to collect imagery of walruses resting on shore in 2018 and 2019 for estimating the abundance of walruses that use the U.S.
Aerial view of the edge of a large walrus herd hauled out on the northwestern shores of Alaska. The image was taken using an unoccupied aerial system, commonly referred to as a survey drone that was flown to collect imagery of walruses resting on shore in 2018 and 2019 for estimating the abundance of walruses that use the U.S.
Orange drone with broad wing fit with two propellers and with two flaps at its base on beach. Female walking towards drone.
This is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
This is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
Sounds from a large herd of walruses resting on Alaskan shores of the Chukchi Sea recorded. Deep full barks and calls of individual walruses near the edge of the herd are audible over a continuous rhythmic humming sound that arises from the calls of tens of thousands of walrsues from deeper within the herd.
Sounds from a large herd of walruses resting on Alaskan shores of the Chukchi Sea recorded. Deep full barks and calls of individual walruses near the edge of the herd are audible over a continuous rhythmic humming sound that arises from the calls of tens of thousands of walrsues from deeper within the herd.
USGS uses small uncrewed aerial systems, also known as drones for science, to survey walrus herds and carcasses on remote Alaskan beaches. The USGS visual observer, Christina Ahlstrom, keeps her eyes on the survey drone while the remote pilot prepares it to survey the walrus herd that is visible in the distance behind her on the beach.
USGS uses small uncrewed aerial systems, also known as drones for science, to survey walrus herds and carcasses on remote Alaskan beaches. The USGS visual observer, Christina Ahlstrom, keeps her eyes on the survey drone while the remote pilot prepares it to survey the walrus herd that is visible in the distance behind her on the beach.
Orange drone on beach with several walrus carcasses near shoreline. Close up of dead young walrus on rocky sandy beach.
This is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
This is B-roll video collected during the fall of 2024 on the Alaskan shores of the Chukchi Sea.
Aerial survey drone prepared for flight positioned on the beach near walrus calf carcasses. When sea ice retreats from large regions of the Chukchi Sea large herds of female and young walruses come to shore to rest.
Aerial survey drone prepared for flight positioned on the beach near walrus calf carcasses. When sea ice retreats from large regions of the Chukchi Sea large herds of female and young walruses come to shore to rest.
USGS is flying drones for science, small uncrewed areal systems (sUAS), to surveys walruses when they rest on shore. The sUAS makes minimal sound due it is broad wing and is flown high above the walrus herds to enables survey data collection with minimal risk to walruses.
USGS is flying drones for science, small uncrewed areal systems (sUAS), to surveys walruses when they rest on shore. The sUAS makes minimal sound due it is broad wing and is flown high above the walrus herds to enables survey data collection with minimal risk to walruses.
Two adult walrus carcasses on the beach observed during the summer after a large group of walruses had rested on shore. USGS is collaborating with the North Slope Borough Department of Wildlife Management to screen walruses for wildlife diseases and algal toxins. The University of Alaska Fairbanks is collaborating with USGS to validate drone survey metho
Two adult walrus carcasses on the beach observed during the summer after a large group of walruses had rested on shore. USGS is collaborating with the North Slope Borough Department of Wildlife Management to screen walruses for wildlife diseases and algal toxins. The University of Alaska Fairbanks is collaborating with USGS to validate drone survey metho
This is a community flyer for distribution in Point Lay, Alaska, to alert community members of USGS activities in the area. A collaborative team of USGS, the North Slope Borough, University of Alaska Fairbanks, and Point Lay residents will assist in surveys of walrus carcasses at a remote coastal haulout that has been used by hundreds of thousands of walruses e
This is a community flyer for distribution in Point Lay, Alaska, to alert community members of USGS activities in the area. A collaborative team of USGS, the North Slope Borough, University of Alaska Fairbanks, and Point Lay residents will assist in surveys of walrus carcasses at a remote coastal haulout that has been used by hundreds of thousands of walruses e
This image shows the estimated outline and area (in square meters) occupied by Pacific walrus at a large coastal haulout in Chukotka Russia in 2023 at Cape Serdtse Kamen. The image is derived from images in 2022 and 2023 from a variety of Earth observing satellite imagery sources collected at known walrus coastal haulouts in Alaska and Chukotka, Russia.
This image shows the estimated outline and area (in square meters) occupied by Pacific walrus at a large coastal haulout in Chukotka Russia in 2023 at Cape Serdtse Kamen. The image is derived from images in 2022 and 2023 from a variety of Earth observing satellite imagery sources collected at known walrus coastal haulouts in Alaska and Chukotka, Russia.
This image shows the estimated area (in square meters) occupied by Pacific walrus at eight coastal haulouts in northern Alaska and Chukotka Russia in 2023 (walrus were detected at two haulouts in 2023: Point Lay, Alaska and Cape Serdtse Kamen, Chukotka).
This image shows the estimated area (in square meters) occupied by Pacific walrus at eight coastal haulouts in northern Alaska and Chukotka Russia in 2023 (walrus were detected at two haulouts in 2023: Point Lay, Alaska and Cape Serdtse Kamen, Chukotka).
Figure showing two Capella Space Synthetic Aperture Radar (SAR) satellite images of a walrus haulout in Russia during and after walrus occupancy. USGS has found that SAR imagery can detect walruses when they rest on shore in large numbers and is pursuing studies to understand how satellite imagery can support improved management of the Pacific walrus.
Figure showing two Capella Space Synthetic Aperture Radar (SAR) satellite images of a walrus haulout in Russia during and after walrus occupancy. USGS has found that SAR imagery can detect walruses when they rest on shore in large numbers and is pursuing studies to understand how satellite imagery can support improved management of the Pacific walrus.
Figure comparing Synthetic Aperture Radar (SAR) satellite images of Pacific walruses on a terrestrial haulout near Point Lay, Alaska, as collected by four different SAR instruments possessing different spatial resolution capabilities (Sentinel-1, Radarsat-2, TerraSAR-X, and Capella Space).
Figure comparing Synthetic Aperture Radar (SAR) satellite images of Pacific walruses on a terrestrial haulout near Point Lay, Alaska, as collected by four different SAR instruments possessing different spatial resolution capabilities (Sentinel-1, Radarsat-2, TerraSAR-X, and Capella Space).
Sea World Orlando marine mammal trainers, Kelly Trotto, Josh Boepple and Matt Oddi, measure a healthy mature female walrus in support of a USGS study that seeks to develop methods to monitor walrus body condition from survey drones flown high above walruses where they rest on shore. With this new tool, USGS intends to examine the environmental factors that affe
Sea World Orlando marine mammal trainers, Kelly Trotto, Josh Boepple and Matt Oddi, measure a healthy mature female walrus in support of a USGS study that seeks to develop methods to monitor walrus body condition from survey drones flown high above walruses where they rest on shore. With this new tool, USGS intends to examine the environmental factors that affe
Indianapolis Zoo marine mammal trainers, Erika Allen and Sydney Pitts, measure a healthy female walrus in support of a USGS study that seeks to develop methods to monitor walrus body condition from survey drones flown high above walruses where they rest on shore. With this new tool, USGS intends to examine the environmental factors that affect walrus body condi
Indianapolis Zoo marine mammal trainers, Erika Allen and Sydney Pitts, measure a healthy female walrus in support of a USGS study that seeks to develop methods to monitor walrus body condition from survey drones flown high above walruses where they rest on shore. With this new tool, USGS intends to examine the environmental factors that affect walrus body condi
This is a graphical abstract for a publication by the USGS that evaluates satellite imagery for monitoring large Pacific walrus haulouts in northwestern Alaska.
This is a graphical abstract for a publication by the USGS that evaluates satellite imagery for monitoring large Pacific walrus haulouts in northwestern Alaska.
Aerial view of a large walrus haulout on the northwestern shores of Alaska. The image was taken using an unoccupied aerial system, commonly referred to as a survey drone. This survey was flown to collect imagery of walruses resting on shore for purposes of estimating the abundance of walruses that use the U.S. Chukchi Sea waters during the autumn.
Aerial view of a large walrus haulout on the northwestern shores of Alaska. The image was taken using an unoccupied aerial system, commonly referred to as a survey drone. This survey was flown to collect imagery of walruses resting on shore for purposes of estimating the abundance of walruses that use the U.S. Chukchi Sea waters during the autumn.
An adult female Pacific walrus resting on the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
An adult female Pacific walrus resting on the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
A young male Pacific walrus resting on the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
A young male Pacific walrus resting on the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
A young male Pacific walrus moving up the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
A young male Pacific walrus moving up the beach of the eastern shore of the Chukchi Sea (Photo taken during USGS research efforts permitted under US Fish and Wildlife Service Permit No. MA801652-7.)
Aerial view of walruses crowded tightly on a thin strip of land surrounded by sea water.
When sea ice is absent in the Chukchi Sea region, walruses gather in large numbers along the northwestern coast of Alaska to rest on shore. USGS has worked with local communities and partners across the Bering Strait to develop methods to estimate regional abundance of walruses using these coastal haulouts and to understand the population consequences of resti
When sea ice is absent in the Chukchi Sea region, walruses gather in large numbers along the northwestern coast of Alaska to rest on shore. USGS has worked with local communities and partners across the Bering Strait to develop methods to estimate regional abundance of walruses using these coastal haulouts and to understand the population consequences of resti
Aerial view of the edge of a large walrus herd hauled out on the northwestern shores of Alaska. The image was taken using an unoccupied aerial system, commonly referred to as a survey drone that was flown to collect imagery of walruses resting on shore in 2018 and 2019 for estimating the abundance of walruses that use the U.S.
Aerial view of the edge of a large walrus herd hauled out on the northwestern shores of Alaska. The image was taken using an unoccupied aerial system, commonly referred to as a survey drone that was flown to collect imagery of walruses resting on shore in 2018 and 2019 for estimating the abundance of walruses that use the U.S.
*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