The USGS Alaska Science Center has had a focus on addressing science questions related to geese in Alaska for decades. Information on these species is critical because all are important resources for subsistence and sport hunters in the state and outside of Alaska where these birds spend the winter.
The large majority of goose populations in Alaska breed on national wildlife refuges (managed by the U.S. Fish and Wildlife Service) and large numbers of black brant geese undergo their flightless molting period on lands managed by the Bureau of Land Management on the North Slope of Alaska. Therefore, changes in population size and trend are of interest to these resource management agencies.
Return to Ecosystems >> Terrestrial Ecosystems >> Waterfowl Research
Q&A: Improving Aerial Surveys of Geese in Alaska with Aerial Imagery
New aerial imagery and automated counting methods are helping to optimize surveys and improve population estimates.
Black Brant
Black Brant are a circumpolar species that nest in Arctic and sub-arctic environments and undergo long-distance migrations to mid and southern latitudes for winter. In Alaska, Black Brant migrate from breeding areas in western and northern Alaska to wintering areas that now include Izembek National Wildlife Refuge, Alaska, and areas as far south as the Baja Peninsula of Mexico. Black Brant spend the entire year in coastal areas, foraging primarily on sea grasses and coastal sedges, which fuels their long-distance migrations and provides forage for adults and goslings.
Black Brant are a species of special management concern because of shifting winter distribution patterns and declining breeding population size on the Yukon-Kuskokwim Delta (YKD), where the majority of Black Brant are assumed to nest. The annual number of nests on the YKD has declined 2–4% per year over the last 20 years and annual survival and recruitment of juvenile birds are also low. These changes appear to be linked to variation in abundance and availability of their primary food source, eelgrass, during the non-breeding period (September-May) and changes to coastal habitats on the YKD.
However, positive changes to habitats used by Black Brant are simultaneously occurring on the North Slope of Alaska and birds are responding by increasing in number. USGS Alaska Science Center research on Black Brant is focused on determining drivers of change in habitat and population size at breeding and wintering areas.
White-fronted Geese
White-fronted Geese are a circumpolar species, breeding in tundra areas across Russia, North America, and Greenland. In North America, this species breeds across wide areas of Alaska and Arctic Canada, wintering in wetlands and agricultural areas of Pacific states, Mexico, and along the Gulf Coast.
This broad distribution complicates understanding and management of population trends because of the many different factors influencing productivity and survival of birds across the landscape. Much of the research conducted by the USGS Alaska Science Center on White-fronted Geese has been on migration patterns, population differences, nutrition, survival, and nesting biology. These studies have helped to define populations and the drivers unique to each population.
Snow Geese
The Snow Goose is a circumpolar species and one of the most abundant in the world. It typically nests in large colonies in arctic areas of North America, Russia, and Greenland. In North America, Snow Geese spend the winter throughout the lower-48 U.S. and in Mexico. The species is gregarious and a voracious forager of plant material.
This species has taken advantage of new agricultural lands and waste grain area, and its population has rapidly grown as a result of these new foraging opportunities. In some areas, populations have grown so rapidly and so large that large amounts of breeding and wintering habitat have been damaged by foraging flocks. Snow Geese are the most rapidly increasing species of waterbird on the Arctic Coastal Plain of Alaska and management agencies are concerned that they may outcompete Black Brant for nesting and brood rearing habitat.
Experience with Snow Geese elsewhere in North America has demonstrated the importance of managing their populations before they become overabundant. Rapidly increasing Snow Goose populations may cause considerable damage of vegetation in nesting areas.
Past USGS Alaska Science Center research has focused on foraging ecology of Snow Geese in the Arctic. Current research is taking place within the USGS Changing Arctic Ecosystems Initiative and is examining the increase of Snow Geese on the Arctic Coastal Plain of Alaska and impacts to other species, such as Black Brant, that are nesting in the same area.
Emperor Geese
The Emperor Goose is an endemic species to the Beringia Region of Alaska and far eastern Russia. The species nests in coastal tundra of western Alaska and eastern Russia and winters on rocky coastal shorelines throughout the Aleutian Islands, the Alaska Peninsula and Kodiak Island. Alaska’s population of Emperor Geese declined precipitously in the 1960’s by more than 50% but have recovered slightly since then.
USGS Alaska Science Center research on Emperor Geese have been focused on factors responsible for the population decline, such as disease, survival, and predation during the breeding season. Research has also filled gaps in our knowledge about this species with regards to its migration and molting ecology. Current research is focused on disease as a demographic constraint to population recovery and wintering ecology.
Cackling and Canada Geese
Formerly considered a single species (the Canada Goose), these two species are widespread throughout North America. These species are also highly unique due to their many different size and plumage color categories that have been recognized as separate subspecies. Each subspecies roughly corresponds to different breeding populations, each of which with their own population trend and habitat affinities.
Recently, some populations of Canada Geese have increased as a result of new agricultural crops grown during winter in the lower-48. These increased wintering populations can cause damage to crops and complicate management objectives through the annual cycle of different subspecies. In some cases, subspecies are difficult to distinguish, further complicating management when some populations are increasing and others decreasing.
USGS Alaska Science Center research has focused on providing science information on how to delineate populations and identify subspecies during harvest surveys. Research in Alaska has also focused on drivers of population trends for subspecies and populations that were of conservation concern, such as the Aleutian Canada Goose and Dusky Canada Goose.
Below are other science projects associated with this project.
Waterfowl Research
Q&A: Improving Aerial Surveys of Geese in Alaska with Aerial Imagery
The USGS Alaska Science Center has had a focus on addressing science questions related to geese in Alaska for decades. Information on these species is critical because all are important resources for subsistence and sport hunters in the state and outside of Alaska where these birds spend the winter.
The large majority of goose populations in Alaska breed on national wildlife refuges (managed by the U.S. Fish and Wildlife Service) and large numbers of black brant geese undergo their flightless molting period on lands managed by the Bureau of Land Management on the North Slope of Alaska. Therefore, changes in population size and trend are of interest to these resource management agencies.
Return to Ecosystems >> Terrestrial Ecosystems >> Waterfowl Research
Q&A: Improving Aerial Surveys of Geese in Alaska with Aerial Imagery
New aerial imagery and automated counting methods are helping to optimize surveys and improve population estimates.
Black Brant
Black Brant are a circumpolar species that nest in Arctic and sub-arctic environments and undergo long-distance migrations to mid and southern latitudes for winter. In Alaska, Black Brant migrate from breeding areas in western and northern Alaska to wintering areas that now include Izembek National Wildlife Refuge, Alaska, and areas as far south as the Baja Peninsula of Mexico. Black Brant spend the entire year in coastal areas, foraging primarily on sea grasses and coastal sedges, which fuels their long-distance migrations and provides forage for adults and goslings.
Black Brant are a species of special management concern because of shifting winter distribution patterns and declining breeding population size on the Yukon-Kuskokwim Delta (YKD), where the majority of Black Brant are assumed to nest. The annual number of nests on the YKD has declined 2–4% per year over the last 20 years and annual survival and recruitment of juvenile birds are also low. These changes appear to be linked to variation in abundance and availability of their primary food source, eelgrass, during the non-breeding period (September-May) and changes to coastal habitats on the YKD.
However, positive changes to habitats used by Black Brant are simultaneously occurring on the North Slope of Alaska and birds are responding by increasing in number. USGS Alaska Science Center research on Black Brant is focused on determining drivers of change in habitat and population size at breeding and wintering areas.
White-fronted Geese
White-fronted Geese are a circumpolar species, breeding in tundra areas across Russia, North America, and Greenland. In North America, this species breeds across wide areas of Alaska and Arctic Canada, wintering in wetlands and agricultural areas of Pacific states, Mexico, and along the Gulf Coast.
This broad distribution complicates understanding and management of population trends because of the many different factors influencing productivity and survival of birds across the landscape. Much of the research conducted by the USGS Alaska Science Center on White-fronted Geese has been on migration patterns, population differences, nutrition, survival, and nesting biology. These studies have helped to define populations and the drivers unique to each population.
Snow Geese
The Snow Goose is a circumpolar species and one of the most abundant in the world. It typically nests in large colonies in arctic areas of North America, Russia, and Greenland. In North America, Snow Geese spend the winter throughout the lower-48 U.S. and in Mexico. The species is gregarious and a voracious forager of plant material.
This species has taken advantage of new agricultural lands and waste grain area, and its population has rapidly grown as a result of these new foraging opportunities. In some areas, populations have grown so rapidly and so large that large amounts of breeding and wintering habitat have been damaged by foraging flocks. Snow Geese are the most rapidly increasing species of waterbird on the Arctic Coastal Plain of Alaska and management agencies are concerned that they may outcompete Black Brant for nesting and brood rearing habitat.
Experience with Snow Geese elsewhere in North America has demonstrated the importance of managing their populations before they become overabundant. Rapidly increasing Snow Goose populations may cause considerable damage of vegetation in nesting areas.
Past USGS Alaska Science Center research has focused on foraging ecology of Snow Geese in the Arctic. Current research is taking place within the USGS Changing Arctic Ecosystems Initiative and is examining the increase of Snow Geese on the Arctic Coastal Plain of Alaska and impacts to other species, such as Black Brant, that are nesting in the same area.
Emperor Geese
The Emperor Goose is an endemic species to the Beringia Region of Alaska and far eastern Russia. The species nests in coastal tundra of western Alaska and eastern Russia and winters on rocky coastal shorelines throughout the Aleutian Islands, the Alaska Peninsula and Kodiak Island. Alaska’s population of Emperor Geese declined precipitously in the 1960’s by more than 50% but have recovered slightly since then.
USGS Alaska Science Center research on Emperor Geese have been focused on factors responsible for the population decline, such as disease, survival, and predation during the breeding season. Research has also filled gaps in our knowledge about this species with regards to its migration and molting ecology. Current research is focused on disease as a demographic constraint to population recovery and wintering ecology.
Cackling and Canada Geese
Formerly considered a single species (the Canada Goose), these two species are widespread throughout North America. These species are also highly unique due to their many different size and plumage color categories that have been recognized as separate subspecies. Each subspecies roughly corresponds to different breeding populations, each of which with their own population trend and habitat affinities.
Recently, some populations of Canada Geese have increased as a result of new agricultural crops grown during winter in the lower-48. These increased wintering populations can cause damage to crops and complicate management objectives through the annual cycle of different subspecies. In some cases, subspecies are difficult to distinguish, further complicating management when some populations are increasing and others decreasing.
USGS Alaska Science Center research has focused on providing science information on how to delineate populations and identify subspecies during harvest surveys. Research in Alaska has also focused on drivers of population trends for subspecies and populations that were of conservation concern, such as the Aleutian Canada Goose and Dusky Canada Goose.
Below are other science projects associated with this project.