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Loon Research

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By Alaska Science Center January 2, 2024

Scientists at the USGS Alaska Science Center have conducted research on Alaska’s three loon species since the late 1970s. Loons rely on freshwater lakes for nesting habitat and fish and invertebrates inhabiting lakes and marine ecosystems for food. All three loon species in Alaska occur within the National Petroleum Reserve-Alaska (NPR-A) on Alaska’s northern coast. Research by the USGS is informing distribution and abundance of loons in northern Alaska and how they may respond to environmental and human changes to the northern landscape.

Return to Ecosystems >> Terrestrial Ecosystems

A Red-throated Loon swimming in a small lake
Sources/Usage: Public Domain. View Media Details
A Red-throated Loon swimming in a small lake on the Colville River Delta.(Credit: Ryan Askren, USGS. Public domain.)

The main objectives of the USGS Alaska Science Center loon research program are to: 

  • Provide ecological and demographic information on Alaska’s three loon species.
  • Determine mechanisms for population trends, particularly for the Red-throated Loon (declines noted across much of Alaska) and the Yellow-billed Loon (a candidate species for listing as ‘threatened’ from 2009 to 2014).
  • Provide science information to Department of Interior management agencies and others for their decision-making regarding loons.

Below are other science projects associated with this project.

Below are data or web applications associated with this project.

No Result Found

Below are multimedia items associated with this project.

No results found.

Below are publications associated with this project.

Filter Total Items: 23

Size and retention of breeding territories of yellow-billed loons in Alaska and Canada

Yellow-billed Loons (Gavia adamsii) breed in lakes in the treeless Arctic and are globally rare. Like their sister taxa, the well-documented Common Loon (G. immer) of the boreal forest, Yellow-billed Loons exhibit strong territorial behavior during the breeding season. Little is known about what size territories are required, however, or how readily territories are retained from year to year. An u
Authors
Joel A. Schmutz, Kenneth G. Wright, Christopher R. DeSorbo, Jeff Fair, David C. Evers, Brian D. Uher-Koch, Daniel M. Mulcahy
By
Ecosystems Mission Area, Alaska Science Center

Occupancy of yellow-billed and Pacific loons: evidence for interspecific competition and habitat mediated co-occurrence

Interspecific competition is an important process structuring ecological communities, however, it is difficult to observe in nature. We used an occupancy modelling approach to evaluate evidence of competition between yellow-billed (Gavia adamsii) and Pacific (G. pacifica) loons for nesting lakes on the Arctic Coastal Plain of Alaska. With multiple years of data and survey platforms, we estimated d
Authors
Trevor B. Haynes, Joel A. Schmutz, Mark S. Lindberg, Kenneth G. Wright, Brian D. Uher-Koch, Amanda E. Rosenberger
By
Ecosystems Mission Area, Alaska Science Center

Historic and contemporary mercury exposure and potential risk to yellow-billed loons (Gavia adamsii) breeding in Alaska and Canada

The Yellow-billed Loon (Gavia adamsii) is one of the rarest breeding birds in North America. Because of the small population size and patchy distribution, any stressor to its population is of concern. To determine risks posed by environmental mercury (Hg) loads, we captured 115 Yellow-billed Loons between 2002 and 2012 in the North American Arctic and sampled their blood and/or feather tissues and
Authors
David C. Evers, Joel A. Schmutz, Niladri Basu, Christopher R. DeSorbo, Jeff Fair, Carrie E. Gray, James D. Paruk, Marie Perkins, Kevin Regan, Brian D. Uher-Koch, Kenneth G. Wright
By
Ecosystems Mission Area, Alaska Science Center

Factors influencing nest survival and productivity of Red-throated Loons (Gavia stellata) in Alaska

Red-throated Loon (Gavia stellata) numbers in Alaska have fluctuated dramatically over the past 3 decades; however, the demographic processes contributing to these population dynamics are poorly understood. To examine spatial and temporal variation in productivity, we estimated breeding parameters at 5 sites in Alaska: at Cape Espenberg and the Copper River Delta we estimated nest survival, and at
Authors
Daniel Rizzolo, Joel A. Schmutz, Sarah E. McCloskey, Thomas F. Fondell
By
Ecosystems Mission Area, Alaska Science Center

Changing Arctic ecosystems: ecology of loons in a changing Arctic

The U.S. Geological Survey (USGS) Changing Arctic Ecosystems (CAE) initiative informs key resource management decisions for Arctic Alaska by providing scientific information on current and future ecosystem response to a changing climate. From 2010 to 2014, a key study area for the USGS CAE initiative has been the Arctic Coastal Plain of northern Alaska. This region has experienced rapid warming du
Authors
Brian D. Uher-Koch, Joel A. Schmutz, Mary E. Whalen, John M. Pearce
By
Ecosystems Mission Area, Alaska Science Center

Risk of predation and weather events affect nest site selection by sympatric Pacific (Gavia pacifica) and Yellow-billed (Gavia adamsii) loons in Arctic habitats

Pacific (Gavia pacifica) and Yellow-billed (G. adamsii) loons nest sympatrically in Arctic regions. These related species likely face similar constraints and requirements for nesting success; therefore, use of similar habitats and direct competition for nesting habitat is likely. Both of these loon species must select a breeding lake that provides suitable habitat for nesting and raising chicks; h
Authors
Trevor B. Haynes, Joel A. Schmutz, Mark S. Lindberg, Amanda E. Rosenberger
By
Ecosystems Mission Area, Alaska Science Center

Survival of adult Red-throated Loons (Gavia stellata) may be linked to marine conditions

Large variations in the summering population size of Red-throated Loons (Gavia stellata) have occurred in recent decades in Alaska. Little information exists about annual or seasonal survival rates of adult Red-throated Loons. This study used tracking data from satellite transmitters implanted into 33 Red-throated Loons captured on breeding areas in Alaska to estimate annual survival with the samp
Authors
Joel A. Schmutz
By
Ecosystems Mission Area, Alaska Science Center

Model-Based Predictions of the Effects of Harvest Mortality on Population Size and Trend of Yellow-Billed Loons

Yellow-billed loons (Gavia adamsii) breed in low densities in northern tundra habitats in Alaska, Canada, and Russia. They migrate to coastal marine habitats at mid to high latitudes where they spend their winters. Harvest may occur throughout the annual cycle, but of particular concern are recent reports of harvest from the Bering Strait region, which lies between Alaska and Russia and is an area
Authors
Joel A. Schmutz
By
Ecosystems Mission Area, Alaska Science Center

Red-throated loons (Gavia stellata) breeding in Alaska, USA, are exposed to PCBs while on their Asian wintering grounds

Red-throated loons (Gavia stellata) breeding in Alaska declined 53% during 1977-1993. We compare concentrations of environmental contaminants in red-throated loons among four nesting areas in Alaska and discuss potential ramifications of exposure on reproductive success and population trends. Eggs from the four areas had similar total polychlorinated biphenyl (PCB) concentrations, but eggs from th
Authors
Joel A. Schmutz, K.A. Trust, A.C. Matz

Egg flotation estimates nest age for Pacific and Red-throated Loons

We used Pacific Loon (Gavia pacifica) and Red-throated Loon (G. stellata) nests with known ages to gauge the efficacy of egg flotation for determining nest age in coastal Alaska. Egg flotation accurately estimated nest age for both species; the mean ± 1SD difference between known age and age determined with egg flotation was - 0.05 ± 2.00 d and -0.02 ± 1.63 d for Pacific and Red-throated Loons, re
Authors
Daniel Rizzolo, Joel A. Schmutz
By
Ecosystems Mission Area, Alaska Science Center

Status assessment and conservation plan for the yellow-billed loon (Gavia adamsii)

Because of its restricted range, small population size, specific habitat requirements, and perceived threats to its breeding habitat, the Yellow-billed Loon (Gavia adamsii) is a species of conservation concern to the U.S. Fish and Wildlife Service and the subject of a petition for listing under the Endangered Species Act. This Status Assessment synthesizes current information on population size, t
Authors
Susan L. Earnst
By
Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Scientists at the USGS Alaska Science Center have conducted research on Alaska’s three loon species since the late 1970s. Loons rely on freshwater lakes for nesting habitat and fish and invertebrates inhabiting lakes and marine ecosystems for food. All three loon species in Alaska occur within the National Petroleum Reserve-Alaska (NPR-A) on Alaska’s northern coast. Research by the USGS is informing distribution and abundance of loons in northern Alaska and how they may respond to environmental and human changes to the northern landscape.

Return to Ecosystems >> Terrestrial Ecosystems

A Red-throated Loon swimming in a small lake
Sources/Usage: Public Domain. View Media Details
A Red-throated Loon swimming in a small lake on the Colville River Delta.(Credit: Ryan Askren, USGS. Public domain.)

The main objectives of the USGS Alaska Science Center loon research program are to: 

  • Provide ecological and demographic information on Alaska’s three loon species.
  • Determine mechanisms for population trends, particularly for the Red-throated Loon (declines noted across much of Alaska) and the Yellow-billed Loon (a candidate species for listing as ‘threatened’ from 2009 to 2014).
  • Provide science information to Department of Interior management agencies and others for their decision-making regarding loons.

Below are other science projects associated with this project.

Below are data or web applications associated with this project.

No Result Found

Below are multimedia items associated with this project.

No results found.

Below are publications associated with this project.

Filter Total Items: 23

Size and retention of breeding territories of yellow-billed loons in Alaska and Canada

Yellow-billed Loons (Gavia adamsii) breed in lakes in the treeless Arctic and are globally rare. Like their sister taxa, the well-documented Common Loon (G. immer) of the boreal forest, Yellow-billed Loons exhibit strong territorial behavior during the breeding season. Little is known about what size territories are required, however, or how readily territories are retained from year to year. An u
Authors
Joel A. Schmutz, Kenneth G. Wright, Christopher R. DeSorbo, Jeff Fair, David C. Evers, Brian D. Uher-Koch, Daniel M. Mulcahy
By
Ecosystems Mission Area, Alaska Science Center

Occupancy of yellow-billed and Pacific loons: evidence for interspecific competition and habitat mediated co-occurrence

Interspecific competition is an important process structuring ecological communities, however, it is difficult to observe in nature. We used an occupancy modelling approach to evaluate evidence of competition between yellow-billed (Gavia adamsii) and Pacific (G. pacifica) loons for nesting lakes on the Arctic Coastal Plain of Alaska. With multiple years of data and survey platforms, we estimated d
Authors
Trevor B. Haynes, Joel A. Schmutz, Mark S. Lindberg, Kenneth G. Wright, Brian D. Uher-Koch, Amanda E. Rosenberger
By
Ecosystems Mission Area, Alaska Science Center

Historic and contemporary mercury exposure and potential risk to yellow-billed loons (Gavia adamsii) breeding in Alaska and Canada

The Yellow-billed Loon (Gavia adamsii) is one of the rarest breeding birds in North America. Because of the small population size and patchy distribution, any stressor to its population is of concern. To determine risks posed by environmental mercury (Hg) loads, we captured 115 Yellow-billed Loons between 2002 and 2012 in the North American Arctic and sampled their blood and/or feather tissues and
Authors
David C. Evers, Joel A. Schmutz, Niladri Basu, Christopher R. DeSorbo, Jeff Fair, Carrie E. Gray, James D. Paruk, Marie Perkins, Kevin Regan, Brian D. Uher-Koch, Kenneth G. Wright
By
Ecosystems Mission Area, Alaska Science Center

Factors influencing nest survival and productivity of Red-throated Loons (Gavia stellata) in Alaska

Red-throated Loon (Gavia stellata) numbers in Alaska have fluctuated dramatically over the past 3 decades; however, the demographic processes contributing to these population dynamics are poorly understood. To examine spatial and temporal variation in productivity, we estimated breeding parameters at 5 sites in Alaska: at Cape Espenberg and the Copper River Delta we estimated nest survival, and at
Authors
Daniel Rizzolo, Joel A. Schmutz, Sarah E. McCloskey, Thomas F. Fondell
By
Ecosystems Mission Area, Alaska Science Center

Changing Arctic ecosystems: ecology of loons in a changing Arctic

The U.S. Geological Survey (USGS) Changing Arctic Ecosystems (CAE) initiative informs key resource management decisions for Arctic Alaska by providing scientific information on current and future ecosystem response to a changing climate. From 2010 to 2014, a key study area for the USGS CAE initiative has been the Arctic Coastal Plain of northern Alaska. This region has experienced rapid warming du
Authors
Brian D. Uher-Koch, Joel A. Schmutz, Mary E. Whalen, John M. Pearce
By
Ecosystems Mission Area, Alaska Science Center

Risk of predation and weather events affect nest site selection by sympatric Pacific (Gavia pacifica) and Yellow-billed (Gavia adamsii) loons in Arctic habitats

Pacific (Gavia pacifica) and Yellow-billed (G. adamsii) loons nest sympatrically in Arctic regions. These related species likely face similar constraints and requirements for nesting success; therefore, use of similar habitats and direct competition for nesting habitat is likely. Both of these loon species must select a breeding lake that provides suitable habitat for nesting and raising chicks; h
Authors
Trevor B. Haynes, Joel A. Schmutz, Mark S. Lindberg, Amanda E. Rosenberger
By
Ecosystems Mission Area, Alaska Science Center

Survival of adult Red-throated Loons (Gavia stellata) may be linked to marine conditions

Large variations in the summering population size of Red-throated Loons (Gavia stellata) have occurred in recent decades in Alaska. Little information exists about annual or seasonal survival rates of adult Red-throated Loons. This study used tracking data from satellite transmitters implanted into 33 Red-throated Loons captured on breeding areas in Alaska to estimate annual survival with the samp
Authors
Joel A. Schmutz
By
Ecosystems Mission Area, Alaska Science Center

Model-Based Predictions of the Effects of Harvest Mortality on Population Size and Trend of Yellow-Billed Loons

Yellow-billed loons (Gavia adamsii) breed in low densities in northern tundra habitats in Alaska, Canada, and Russia. They migrate to coastal marine habitats at mid to high latitudes where they spend their winters. Harvest may occur throughout the annual cycle, but of particular concern are recent reports of harvest from the Bering Strait region, which lies between Alaska and Russia and is an area
Authors
Joel A. Schmutz
By
Ecosystems Mission Area, Alaska Science Center

Red-throated loons (Gavia stellata) breeding in Alaska, USA, are exposed to PCBs while on their Asian wintering grounds

Red-throated loons (Gavia stellata) breeding in Alaska declined 53% during 1977-1993. We compare concentrations of environmental contaminants in red-throated loons among four nesting areas in Alaska and discuss potential ramifications of exposure on reproductive success and population trends. Eggs from the four areas had similar total polychlorinated biphenyl (PCB) concentrations, but eggs from th
Authors
Joel A. Schmutz, K.A. Trust, A.C. Matz

Egg flotation estimates nest age for Pacific and Red-throated Loons

We used Pacific Loon (Gavia pacifica) and Red-throated Loon (G. stellata) nests with known ages to gauge the efficacy of egg flotation for determining nest age in coastal Alaska. Egg flotation accurately estimated nest age for both species; the mean ± 1SD difference between known age and age determined with egg flotation was - 0.05 ± 2.00 d and -0.02 ± 1.63 d for Pacific and Red-throated Loons, re
Authors
Daniel Rizzolo, Joel A. Schmutz
By
Ecosystems Mission Area, Alaska Science Center

Status assessment and conservation plan for the yellow-billed loon (Gavia adamsii)

Because of its restricted range, small population size, specific habitat requirements, and perceived threats to its breeding habitat, the Yellow-billed Loon (Gavia adamsii) is a species of conservation concern to the U.S. Fish and Wildlife Service and the subject of a petition for listing under the Endangered Species Act. This Status Assessment synthesizes current information on population size, t
Authors
Susan L. Earnst
By
Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center