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ScienceDaily (Nov. 29, 2007) — One hundred seventy-eight species in the continental U.S. and 39 in Hawaii have the dubious distinction of landing on the newest and most scientifically sound list of America's most imperiled birds. WatchList 2007, a joint effort of Audubon and American Bird Conservancy, reflects a comprehensive analysis of population size and trends, distribution, and threats for 700 bird species in the U.S. It reveals those in greatest need of immediate conservation help simply to survive amid a convergence of environmental challenges, including habitat loss, invasive species and global warming.
"We call this a 'WatchList' but it is really a call to action, because the alternative is to watch these species slip ever closer to oblivion," said Audubon Bird Conservation Director and co-author of the new list, Greg Butcher. "Agreeing on which species are at the greatest risk is the first step in building the public policies, funding support, innovative conservation initiatives and public commitment needed to save them."
The new Audubon/American Bird Conservancy WatchList identifies 59 continental and 39 Hawaiian "red list" species of greatest concern, and 119 more in the "yellow" category of seriously declining or rare species. It is based on the latest available research and assessment from the bird conservation community along with data from the Christmas Bird Count and the annual Breeding Bird Survey. The data were analyzed and weighted according to methods developed through extensive peer review and revision, yielding an improved assessment of actual peril that can be used to determine bird conservation priorities and funding.
"Adoption of this list as the 'industry standard' will help to ensure that conservation resources are allocated to the most important conservation needs," said David Pashley, American Bird Conservancy's Director of Conservation Programs and co-author of the new list. "How quickly and effectively we act to protect and support the species on this list will determine their future; where we've taken aggressive action, we've seen improvement."
Despite ongoing challenges and their continued place on the list, the status of some WatchList species is improving, according to the new data, as broader awareness of their plight has spawned effective conservation action. Several species have benefited from federal protection under the Endangered Species Act (ESA) and now show stabilizing, or even increasing populations. Lacking an ESA designation or the political support needed to secure strong protective measures, others continue to decline.
"Habitat loss due to development, energy exploration and extraction, and the impact of global warming remain serious threats for the most imperiled species, along with others on both the red and yellow lists," said Pashley. "Concerted action will be needed to address these threats."
Listed species may seem unfamiliar to many Americans. Unlike those on Audubon's recent survey of Common Birds in Decline, the species on WatchList are often rare and limited in range. In combination with population declines and new threats, these factors make many of them acutely vulnerable to extinction.
Among the most imperiled species on the list that regularly breed in the continental U.S. are:
Gunnison Sage-Grouse (not on ESA list)
This species is restricted to Southwest Colorado and adjacent Utah. Drought, which is predicted to get worse with increased global warming, is among the factors that have reduced the Gunnison Sage-Grouse population to fewer than 5,000; habitat loss and fragmentation and excessive grazing are other threats. Protection and restoration of contiguous tracts of good habitat is critical.
Lesser Prairie-Chicken (not on ESA list)
Habitat loss and degradation have restricted this species to a number of isolated populations, many of which are on private lands in Kansas, Colorado, Oklahoma, New Mexico, and Texas. Small population size, changing habitat resulting from drought, and climate change threaten continued survival.
California Condor (protected by ESA)
Once reduced to nine individual wild birds, this raptor is slowly recovering, thanks to captive breeding and the release of individuals in California and Arizona. There are now 305 individuals, including 148 free-flying birds. Lead bullets are a critical threat to long-term survival, as fragments poison wild condors that eat the remains of hunters' kills. Audubon California and American Bird Conservancy have spearheaded recent passage of legislation eliminating lead bullets in the range of the condor in that state.
Whooping Crane (protected by ESA)
Unregulated shooting and loss of habitat reduced this species to fewer than 20 individuals around the turn of the 20th Century. Implementation of a recovery plan developed under the Endangered Species Act has resulted in more than a 1000% increase in population to over 200 individuals, and has spawned efforts to establish additional wild breeding populations.
Piping Plover (protected by ESA)
Protection of this shorebird's beachfront nesting grounds is helping to improve the outlook for this species. Human development along beaches, increased beach recreation, disturbance by pets, and increased predation require constant vigilance. Intensive conservation efforts supported by the Endangered Species Act have helped stabilize populations and allowed populations to increase in some regions of the Atlantic and Gulf coasts.
Black-capped Vireo (protected by ESA)
Suburban development, agricultural conversion, and fire suppression in Texas and Oklahoma have decreased available breeding habitat, reducing both the range and population size of this species. Increased predation near human development has further decreased populations, as has parasitism from Brown-headed Cowbirds, which lay their eggs in Black-capped Vireo nests, out-competing the vireo chicks. Innovative conservation efforts on public and private lands seem to be helping some populations recover.
Florida Scrub-Jay (protected by ESA)
Suburban-exurban sprawl and agricultural development have reduced habitat dramatically and isolated many populations. Maintaining natural wildfire regimes will be critical. Although ESA status has increased conservation efforts for this species, it has not been enough to stop loss of habitat.
Golden-cheeked Warbler (protected by ESA)
Breeding is restricted to the Edwards Plateau in Texas, where suburban sprawl and habitat destruction has greatly reduced population size. Winter habitat loss in southern Mexico and Central America may also be affecting populations. Innovative conservation strategies that protect and restore habitat in both the breeding and wintering grounds are underway and needed.
Kirtland's Warbler (protected by ESA)
Dependent on jack pine habitat in northern Michigan, this warbler species has increased more than 600% since the mid-1980s because of management plans implemented under the Endangered Species Act. Singing male counts in the spring have increased from 200 to almost 1,400 (and some singing males are now found in Wisconsin and Ontario). Wild land fire management, control of the parasitic Brown-headed Cowbird, and protection of wintering habitat in the Bahamas remain essential to long-term survival.
Ashy Storm-Petrel (not on ESA list)
Breeding populations are restricted to islands off the west coast of North America. Non-native nest predators and increased gull populations threaten breeding birds, and ocean pollution and overfishing threaten feeding birds.
Kittlitz's Murrelet (not on ESA list)
Breeding and feeding habitat seems to be linked to Alaska's tidewater glaciers, making this species very susceptible to climate change. Oil spills, coastal pollution, and increased disturbance also threaten this species.
Red-cockaded Woodpecker (protected by ESA)
Habitat loss from logging in the Southeast's long-leaf pine forests and suburban and agricultural development have isolated populations and greatly reduced overall population size. Protection strategies developed through the Endangered Species Act are helping populations in many places, but restoration of open long-leaf pine forest is desperately needed.
Spectacled Eider (protected by ESA)
Ingestion of lead shot is believed to be a major problem for this species, along with an increase in nest predation by foxes, mink, gulls, and jaegers in a warming Arctic. In addition, changing sea conditions in winter are affecting the distribution of clams - a preferred winter food. Proposed oil development poses an additional and very significant threat.
Reddish Egret (not on ESA list)
This species forages along the Gulf Coast and is subject to human disturbance at beaches and at nesting sites. It is dependent on high quality coastal habitat for its food. Human coastal development and decreasing water quality are serious threats.
Black Rail (not on ESA list)
This species makes its home in shallow, grassy wetlands along the Atlantic Coast, San Francisco Bay, southern Great Plains and the Lower Colorado River, habitat that is vulnerable to human conversion to other uses, including agriculture or other development. A secretive bird, it needs further study to increase understanding of its natural history, ecological role and conservation needs.
Buff-breasted Sandpiper (not on ESA list)
Traveling each fall from Alaska to Argentina, this species is one of our champion long-distance migrants. Along the way, it faces a great variety of threats, from oil development on its Arctic breeding grounds to grassland conversion to soybean fields on its Argentinean wintering grounds. It needs protected grassy stopover sites all along its migration route.
Saltmarsh Sharp-tailed Sparrow (not on ESA list)
This tiny bird is restricted to a narrow band of saltmarsh along the Atlantic and Gulf Coasts. It is threatened on one side by human coastal developments and on the other by rising sea levels. With even one foot of sea-level rise from global warming, this species will need a lot of help to maintain sufficient habitat for its survival.
Tricolored Blackbird (not on ESA list)
A highly social species, this bird is found in freshwater wetlands in the Pacific states, mainly California. With loss of this habitat, this species increasingly relies on agricultural fields for nesting, leaving chicks vulnerable to the harvest of hay and other crops. Audubon California and other conservationists are working with farmers to maintain agricultural nesting habitat long enough each season to allow the blackbirds to successfully raise their young - potentially spelling the difference between survival and extinction for this highly specialized bird.
Yellow Rail (not on ESA list)
Rails are small, secretive birds that winter in wetlands along the Gulf and Atlantic Coasts. This species prefers to breed in wet grasslands across Canada and the northern tier of states from Minnesota to Maine. These grasslands are easily converted to other uses, so protection of high-quality habitat will be essential for this migratory bird's survival.
Xantus's Murrelet (not on ESA list)
This tiny seabird nests on islands off southern California. Conservationists are tackling the major threat on the nesting grounds - non-native predators like rats and mice. Global warming seems to wreak havoc with the water circulation and availability of food sources in the ocean, causing shortages for this and other coastal seabirds.
Conservation action is also needed beyond the mainland. Hawaii has the highest proportion of native species in peril, primarily because of the state's small land area and wide variety of introduced invasive animal and plant species. In addition, the Hawaiian Islands are particularly vulnerable to global warming. Hawaiian species facing the greatest threats are highlighted in a special section of WatchList.
The combined WatchLists show that imperiled birds - whether on the U.S. mainland or in Hawaii - are vulnerable to many of the same environmental threats, including global warming, habitat loss, pollution, and non-native invasive species. Aggressive conservation action to address these challenges is essential to their survival. "Everyone, from conservation groups to policy-makers and birdwatchers, needs to take a hard look at these lists and use them to inform and hone our conservation approaches and funding priorities while there's still time," says Butcher. "It's astounding that several are so close to the edge but haven't even received Endangered Species Act protection-this list is a reminder that we need to act and act now."
"The WatchList sounds a real warning, but fortunately, when we put our minds and laws to it, as we did with the Bald Eagle, Whooping Crane and California Condor, we can make a difference," said Pashley.
Adapted from materials provided by National Audubon Society.
The new Audubon/American Bird Conservancy WatchList identifies 59 continental and 39 Hawaiian "red list" species of greatest concern, and 119 more in the "yellow" category of seriously declining or rare species. It is based on the latest available research and assessment from the bird conservation community along with data from the Christmas Bird Count and the annual Breeding Bird Survey. The data were analyzed and weighted according to methods developed through extensive peer review and revision, yielding an improved assessment of actual peril that can be used to determine bird conservation priorities and funding.
"Adoption of this list as the 'industry standard' will help to ensure that conservation resources are allocated to the most important conservation needs," said David Pashley, American Bird Conservancy's Director of Conservation Programs and co-author of the new list. "How quickly and effectively we act to protect and support the species on this list will determine their future; where we've taken aggressive action, we've seen improvement."
Despite ongoing challenges and their continued place on the list, the status of some WatchList species is improving, according to the new data, as broader awareness of their plight has spawned effective conservation action. Several species have benefited from federal protection under the Endangered Species Act (ESA) and now show stabilizing, or even increasing populations. Lacking an ESA designation or the political support needed to secure strong protective measures, others continue to decline.
"Habitat loss due to development, energy exploration and extraction, and the impact of global warming remain serious threats for the most imperiled species, along with others on both the red and yellow lists," said Pashley. "Concerted action will be needed to address these threats."
Listed species may seem unfamiliar to many Americans. Unlike those on Audubon's recent survey of Common Birds in Decline, the species on WatchList are often rare and limited in range. In combination with population declines and new threats, these factors make many of them acutely vulnerable to extinction.
Among the most imperiled species on the list that regularly breed in the continental U.S. are:
Gunnison Sage-Grouse (not on ESA list)
This species is restricted to Southwest Colorado and adjacent Utah. Drought, which is predicted to get worse with increased global warming, is among the factors that have reduced the Gunnison Sage-Grouse population to fewer than 5,000; habitat loss and fragmentation and excessive grazing are other threats. Protection and restoration of contiguous tracts of good habitat is critical.
Lesser Prairie-Chicken (not on ESA list)
Habitat loss and degradation have restricted this species to a number of isolated populations, many of which are on private lands in Kansas, Colorado, Oklahoma, New Mexico, and Texas. Small population size, changing habitat resulting from drought, and climate change threaten continued survival.
California Condor (protected by ESA)
Once reduced to nine individual wild birds, this raptor is slowly recovering, thanks to captive breeding and the release of individuals in California and Arizona. There are now 305 individuals, including 148 free-flying birds. Lead bullets are a critical threat to long-term survival, as fragments poison wild condors that eat the remains of hunters' kills. Audubon California and American Bird Conservancy have spearheaded recent passage of legislation eliminating lead bullets in the range of the condor in that state.
Whooping Crane (protected by ESA)
Unregulated shooting and loss of habitat reduced this species to fewer than 20 individuals around the turn of the 20th Century. Implementation of a recovery plan developed under the Endangered Species Act has resulted in more than a 1000% increase in population to over 200 individuals, and has spawned efforts to establish additional wild breeding populations.
Piping Plover (protected by ESA)
Protection of this shorebird's beachfront nesting grounds is helping to improve the outlook for this species. Human development along beaches, increased beach recreation, disturbance by pets, and increased predation require constant vigilance. Intensive conservation efforts supported by the Endangered Species Act have helped stabilize populations and allowed populations to increase in some regions of the Atlantic and Gulf coasts.
Black-capped Vireo (protected by ESA)
Suburban development, agricultural conversion, and fire suppression in Texas and Oklahoma have decreased available breeding habitat, reducing both the range and population size of this species. Increased predation near human development has further decreased populations, as has parasitism from Brown-headed Cowbirds, which lay their eggs in Black-capped Vireo nests, out-competing the vireo chicks. Innovative conservation efforts on public and private lands seem to be helping some populations recover.
Florida Scrub-Jay (protected by ESA)
Suburban-exurban sprawl and agricultural development have reduced habitat dramatically and isolated many populations. Maintaining natural wildfire regimes will be critical. Although ESA status has increased conservation efforts for this species, it has not been enough to stop loss of habitat.
Golden-cheeked Warbler (protected by ESA)
Breeding is restricted to the Edwards Plateau in Texas, where suburban sprawl and habitat destruction has greatly reduced population size. Winter habitat loss in southern Mexico and Central America may also be affecting populations. Innovative conservation strategies that protect and restore habitat in both the breeding and wintering grounds are underway and needed.
Kirtland's Warbler (protected by ESA)
Dependent on jack pine habitat in northern Michigan, this warbler species has increased more than 600% since the mid-1980s because of management plans implemented under the Endangered Species Act. Singing male counts in the spring have increased from 200 to almost 1,400 (and some singing males are now found in Wisconsin and Ontario). Wild land fire management, control of the parasitic Brown-headed Cowbird, and protection of wintering habitat in the Bahamas remain essential to long-term survival.
Ashy Storm-Petrel (not on ESA list)
Breeding populations are restricted to islands off the west coast of North America. Non-native nest predators and increased gull populations threaten breeding birds, and ocean pollution and overfishing threaten feeding birds.
Kittlitz's Murrelet (not on ESA list)
Breeding and feeding habitat seems to be linked to Alaska's tidewater glaciers, making this species very susceptible to climate change. Oil spills, coastal pollution, and increased disturbance also threaten this species.
Red-cockaded Woodpecker (protected by ESA)
Habitat loss from logging in the Southeast's long-leaf pine forests and suburban and agricultural development have isolated populations and greatly reduced overall population size. Protection strategies developed through the Endangered Species Act are helping populations in many places, but restoration of open long-leaf pine forest is desperately needed.
Spectacled Eider (protected by ESA)
Ingestion of lead shot is believed to be a major problem for this species, along with an increase in nest predation by foxes, mink, gulls, and jaegers in a warming Arctic. In addition, changing sea conditions in winter are affecting the distribution of clams - a preferred winter food. Proposed oil development poses an additional and very significant threat.
Reddish Egret (not on ESA list)
This species forages along the Gulf Coast and is subject to human disturbance at beaches and at nesting sites. It is dependent on high quality coastal habitat for its food. Human coastal development and decreasing water quality are serious threats.
Black Rail (not on ESA list)
This species makes its home in shallow, grassy wetlands along the Atlantic Coast, San Francisco Bay, southern Great Plains and the Lower Colorado River, habitat that is vulnerable to human conversion to other uses, including agriculture or other development. A secretive bird, it needs further study to increase understanding of its natural history, ecological role and conservation needs.
Buff-breasted Sandpiper (not on ESA list)
Traveling each fall from Alaska to Argentina, this species is one of our champion long-distance migrants. Along the way, it faces a great variety of threats, from oil development on its Arctic breeding grounds to grassland conversion to soybean fields on its Argentinean wintering grounds. It needs protected grassy stopover sites all along its migration route.
Saltmarsh Sharp-tailed Sparrow (not on ESA list)
This tiny bird is restricted to a narrow band of saltmarsh along the Atlantic and Gulf Coasts. It is threatened on one side by human coastal developments and on the other by rising sea levels. With even one foot of sea-level rise from global warming, this species will need a lot of help to maintain sufficient habitat for its survival.
Tricolored Blackbird (not on ESA list)
A highly social species, this bird is found in freshwater wetlands in the Pacific states, mainly California. With loss of this habitat, this species increasingly relies on agricultural fields for nesting, leaving chicks vulnerable to the harvest of hay and other crops. Audubon California and other conservationists are working with farmers to maintain agricultural nesting habitat long enough each season to allow the blackbirds to successfully raise their young - potentially spelling the difference between survival and extinction for this highly specialized bird.
Yellow Rail (not on ESA list)
Rails are small, secretive birds that winter in wetlands along the Gulf and Atlantic Coasts. This species prefers to breed in wet grasslands across Canada and the northern tier of states from Minnesota to Maine. These grasslands are easily converted to other uses, so protection of high-quality habitat will be essential for this migratory bird's survival.
Xantus's Murrelet (not on ESA list)
This tiny seabird nests on islands off southern California. Conservationists are tackling the major threat on the nesting grounds - non-native predators like rats and mice. Global warming seems to wreak havoc with the water circulation and availability of food sources in the ocean, causing shortages for this and other coastal seabirds.
Conservation action is also needed beyond the mainland. Hawaii has the highest proportion of native species in peril, primarily because of the state's small land area and wide variety of introduced invasive animal and plant species. In addition, the Hawaiian Islands are particularly vulnerable to global warming. Hawaiian species facing the greatest threats are highlighted in a special section of WatchList.
The combined WatchLists show that imperiled birds - whether on the U.S. mainland or in Hawaii - are vulnerable to many of the same environmental threats, including global warming, habitat loss, pollution, and non-native invasive species. Aggressive conservation action to address these challenges is essential to their survival. "Everyone, from conservation groups to policy-makers and birdwatchers, needs to take a hard look at these lists and use them to inform and hone our conservation approaches and funding priorities while there's still time," says Butcher. "It's astounding that several are so close to the edge but haven't even received Endangered Species Act protection-this list is a reminder that we need to act and act now."
"The WatchList sounds a real warning, but fortunately, when we put our minds and laws to it, as we did with the Bald Eagle, Whooping Crane and California Condor, we can make a difference," said Pashley.
Adapted from materials provided by National Audubon Society.
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