American woodcock (Scolopax minor; woodcock) are monitored, in part, by counts of displaying male... more American woodcock (Scolopax minor; woodcock) are monitored, in part, by counts of displaying male woodcock collected via the American Woodcock Singing Ground Survey (SGS), which suggests long‐term, range‐wide declines in woodcock populations. Data from the SGS have been used extensively to develop conservation plans, direct management actions, and understand causes of decline. To avoid bias, the SGS should be timed to avoid spring migration, and the distribution of survey routes should coincide with woodcock breeding distribution. Our objectives for this research were to evaluate SGS timing with the phenology of male woodcock migration, relate the spatial coverage of the SGS to male woodcock breeding distributions, and explore other sources of variation in woodcock migration timing. We marked 133 male woodcock captured throughout eastern North America with global positioning system (GPS) transmitters during 2019–2022, and compared the timing of their spring migration with the spatio...
King (Rallus elegans, KIRA) and Clapper (Rallus crepitans, CLRA) rail samples genotyped at 13 spe... more King (Rallus elegans, KIRA) and Clapper (Rallus crepitans, CLRA) rail samples genotyped at 13 species-diagnostic SNP markers. Data includes id, site number (corresponding to Figure 2), site name, and genotypes. Genotypes are identified as follows: 1=A, 2= T, 3=C, 4=G, and 0 indicates no genotype was assigned
Hybridization is common in bird populations but can be challenging for management, especially if ... more Hybridization is common in bird populations but can be challenging for management, especially if one of the two parent species is of greater conservation concern than the other. King rails (Rallus elegans) and clapper rails (R. crepitans) are two marsh bird species with similar morphologies, behaviors, and overlapping distributions. The two species are found along a salinity gradient with the king rail in freshwater marshes and the clapper in estuarine marshes. However, this separation is not absolute; they are occasionally sympatric, and there are reports of interbreeding. In Virginia, USA, both king and clapper rails are identified by the state as Species of Greater Conservation Need, although clappers are thought to be more abundant and king rails have a higher priority ranking. We used a mitochondrial DNA marker and 13 diagnostic nuclear single nucleotide polymorphisms (SNPs) to identify species, classify the degree of introgression, and explore the evolutionary history of introgression in two putative clapper rail focal populations along a salinity gradient in coastal Virginia. Genetic analyses revealed cryptic introgression with site-specific rates of admixture. We identified a pattern of introgression where clapper rail alleles predominate in brackish marshes. These results suggest clapper rails may be displacing king rails in Virginia coastal waterways, most likely as a result of ecological selection. As introgression can result in various outcomes from outbreeding depression to local adaptation, continued monitoring of these populations would allow further exploration of hybrid fitness and inform conservation management
WINTER SURVIVAL OF FEMALE AMERICAN BLACK DUCKS ON THE ATLANTIC COAST ... MICHAEL J. CONROY,'... more WINTER SURVIVAL OF FEMALE AMERICAN BLACK DUCKS ON THE ATLANTIC COAST ... MICHAEL J. CONROY,' US Fish and Wildlife Service, Patuxent Wildlife Research Center, Laurel, MD 20708 GARY R. COSTANZO, New York Cooperative Fish and Wildlife ...
The Eastern Population (EP) of Tundra Swans Cygnus columbianus columbianus breeds from the Alaska... more The Eastern Population (EP) of Tundra Swans Cygnus columbianus columbianus breeds from the Alaskan North Slope to eastern Hudson Bay in Canada and winters in the eastern United States. Breeding and migration habitats have been difficult to identify because of the species' vast and remote breeding range and its long-distance migration.
Wildlife managers in the State of Virginia developed an integrated Canada goose (Branta canadensi... more Wildlife managers in the State of Virginia developed an integrated Canada goose (Branta canadensis) damage management program in 1996 to address increasing damage caused by resident (non-migratory) Canada geese, primarily in urban/suburban areas. The previous Canada goose damage management program relied primarily on harassment and relocation. The integrated program was made available to citizens, homeowner associations, businesses, organizations, city and county governments, and state and federal agencies in 1997. The Integrated Canada Goose Management Program was developed by U.S. Department of Agriculture-Animal and Plant Health Inspection Service-Wildlife Services, Virginia Department of Agriculture and Consumer Services, Virginia Department of Game and Inland Fisheries, and the U.S. Fish and Wildlife Service. An aggregate of environmental, hunting, animal welfare, and agriculture groups, airports, golf courses, utilities, homeowner associations, federal agencies, and state and ...
The Eastern Population (EP) of Tundra Swans Cygnus columbianus columbianus breeds from the Alaska... more The Eastern Population (EP) of Tundra Swans Cygnus columbianus columbianus breeds from the Alaskan North Slope to eastern Hudson Bay in Canada and winters in the eastern United States. Breeding and migration habitats have been difficult to identify because of the species’ vast and remote breeding range and its long-distance migration. A total of 43 female EP Tundra Swans were caught in Maryland, North Carolina, Pennsylvania and Virginia and marked with satellite transmitters to follow annual movements, delineate migration routes and determine Bird Conservation Region (BCR) use for EP Tundra Swans from November 2000–March 2002. Marked EP Tundra Swans spent approximately 3.5 months on breeding areas, 3.5 months on wintering areas and 5 months on staging areas, highlighting the importance of migratory habitats to these birds. Marked birds used 15 different ecologically distinct BCRs throughout the year: 10 during the spring, 11 during the autumn, four during the summer and six during t...
Populations of local breeding or resident Canada geese (Branta canadensis) are widespread and are... more Populations of local breeding or resident Canada geese (Branta canadensis) are widespread and are increasing in the United States (Sheaffer et al. 1987). As these populations have grown, so has the interest in these birds for aesthetic, recreational, and research purposes. This growth also has led to an increase in conflicts with human populations (Nelson and Oetting 1981, Conover and Chasko 1985). Examples of conflicts include damage or nuisance problems on lawns, golf courses, public beaches, parks, and agricultural fields. Other concerns include human health and safety issues such as aircraft collision risk and increased nutrient loading of ponds and public water supplies. Resident geese often are captured and relocated to resolve nuisance problems (Woronecki et al. 1990) or trapped for marking purposes during research or management studies. Trapping is often conducted during the bird's annual prebasic molt in mid-summer. Geese lose all their flight feathers simultaneously du...
American woodcock (Scolopax minor; woodcock) are monitored, in part, by counts of displaying male... more American woodcock (Scolopax minor; woodcock) are monitored, in part, by counts of displaying male woodcock collected via the American Woodcock Singing Ground Survey (SGS), which suggests long‐term, range‐wide declines in woodcock populations. Data from the SGS have been used extensively to develop conservation plans, direct management actions, and understand causes of decline. To avoid bias, the SGS should be timed to avoid spring migration, and the distribution of survey routes should coincide with woodcock breeding distribution. Our objectives for this research were to evaluate SGS timing with the phenology of male woodcock migration, relate the spatial coverage of the SGS to male woodcock breeding distributions, and explore other sources of variation in woodcock migration timing. We marked 133 male woodcock captured throughout eastern North America with global positioning system (GPS) transmitters during 2019–2022, and compared the timing of their spring migration with the spatio...
King (Rallus elegans, KIRA) and Clapper (Rallus crepitans, CLRA) rail samples genotyped at 13 spe... more King (Rallus elegans, KIRA) and Clapper (Rallus crepitans, CLRA) rail samples genotyped at 13 species-diagnostic SNP markers. Data includes id, site number (corresponding to Figure 2), site name, and genotypes. Genotypes are identified as follows: 1=A, 2= T, 3=C, 4=G, and 0 indicates no genotype was assigned
Hybridization is common in bird populations but can be challenging for management, especially if ... more Hybridization is common in bird populations but can be challenging for management, especially if one of the two parent species is of greater conservation concern than the other. King rails (Rallus elegans) and clapper rails (R. crepitans) are two marsh bird species with similar morphologies, behaviors, and overlapping distributions. The two species are found along a salinity gradient with the king rail in freshwater marshes and the clapper in estuarine marshes. However, this separation is not absolute; they are occasionally sympatric, and there are reports of interbreeding. In Virginia, USA, both king and clapper rails are identified by the state as Species of Greater Conservation Need, although clappers are thought to be more abundant and king rails have a higher priority ranking. We used a mitochondrial DNA marker and 13 diagnostic nuclear single nucleotide polymorphisms (SNPs) to identify species, classify the degree of introgression, and explore the evolutionary history of introgression in two putative clapper rail focal populations along a salinity gradient in coastal Virginia. Genetic analyses revealed cryptic introgression with site-specific rates of admixture. We identified a pattern of introgression where clapper rail alleles predominate in brackish marshes. These results suggest clapper rails may be displacing king rails in Virginia coastal waterways, most likely as a result of ecological selection. As introgression can result in various outcomes from outbreeding depression to local adaptation, continued monitoring of these populations would allow further exploration of hybrid fitness and inform conservation management
WINTER SURVIVAL OF FEMALE AMERICAN BLACK DUCKS ON THE ATLANTIC COAST ... MICHAEL J. CONROY,'... more WINTER SURVIVAL OF FEMALE AMERICAN BLACK DUCKS ON THE ATLANTIC COAST ... MICHAEL J. CONROY,' US Fish and Wildlife Service, Patuxent Wildlife Research Center, Laurel, MD 20708 GARY R. COSTANZO, New York Cooperative Fish and Wildlife ...
The Eastern Population (EP) of Tundra Swans Cygnus columbianus columbianus breeds from the Alaska... more The Eastern Population (EP) of Tundra Swans Cygnus columbianus columbianus breeds from the Alaskan North Slope to eastern Hudson Bay in Canada and winters in the eastern United States. Breeding and migration habitats have been difficult to identify because of the species' vast and remote breeding range and its long-distance migration.
Wildlife managers in the State of Virginia developed an integrated Canada goose (Branta canadensi... more Wildlife managers in the State of Virginia developed an integrated Canada goose (Branta canadensis) damage management program in 1996 to address increasing damage caused by resident (non-migratory) Canada geese, primarily in urban/suburban areas. The previous Canada goose damage management program relied primarily on harassment and relocation. The integrated program was made available to citizens, homeowner associations, businesses, organizations, city and county governments, and state and federal agencies in 1997. The Integrated Canada Goose Management Program was developed by U.S. Department of Agriculture-Animal and Plant Health Inspection Service-Wildlife Services, Virginia Department of Agriculture and Consumer Services, Virginia Department of Game and Inland Fisheries, and the U.S. Fish and Wildlife Service. An aggregate of environmental, hunting, animal welfare, and agriculture groups, airports, golf courses, utilities, homeowner associations, federal agencies, and state and ...
The Eastern Population (EP) of Tundra Swans Cygnus columbianus columbianus breeds from the Alaska... more The Eastern Population (EP) of Tundra Swans Cygnus columbianus columbianus breeds from the Alaskan North Slope to eastern Hudson Bay in Canada and winters in the eastern United States. Breeding and migration habitats have been difficult to identify because of the species’ vast and remote breeding range and its long-distance migration. A total of 43 female EP Tundra Swans were caught in Maryland, North Carolina, Pennsylvania and Virginia and marked with satellite transmitters to follow annual movements, delineate migration routes and determine Bird Conservation Region (BCR) use for EP Tundra Swans from November 2000–March 2002. Marked EP Tundra Swans spent approximately 3.5 months on breeding areas, 3.5 months on wintering areas and 5 months on staging areas, highlighting the importance of migratory habitats to these birds. Marked birds used 15 different ecologically distinct BCRs throughout the year: 10 during the spring, 11 during the autumn, four during the summer and six during t...
Populations of local breeding or resident Canada geese (Branta canadensis) are widespread and are... more Populations of local breeding or resident Canada geese (Branta canadensis) are widespread and are increasing in the United States (Sheaffer et al. 1987). As these populations have grown, so has the interest in these birds for aesthetic, recreational, and research purposes. This growth also has led to an increase in conflicts with human populations (Nelson and Oetting 1981, Conover and Chasko 1985). Examples of conflicts include damage or nuisance problems on lawns, golf courses, public beaches, parks, and agricultural fields. Other concerns include human health and safety issues such as aircraft collision risk and increased nutrient loading of ponds and public water supplies. Resident geese often are captured and relocated to resolve nuisance problems (Woronecki et al. 1990) or trapped for marking purposes during research or management studies. Trapping is often conducted during the bird's annual prebasic molt in mid-summer. Geese lose all their flight feathers simultaneously du...
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