Dispersal and survival rates of adult and juvenile Red–tailed tropicbirds (Phaethon rubricauda) e... more Dispersal and survival rates of adult and juvenile Red–tailed tropicbirds (Phaethon rubricauda) exposed to potential contaminants
GULLS WINTERING IN FLORIDA: CHRISTMAS BIRD COUNT ANALYSIS Elizabeth Anne Schreiber and Ralph W. S... more GULLS WINTERING IN FLORIDA: CHRISTMAS BIRD COUNT ANALYSIS Elizabeth Anne Schreiber and Ralph W. Schreiber Introduction Christmas Bird Counts (CBC's) provide a unique data source for determining long term avian population trends over wide geographic areas (Kadlec and Drury 1968, Bystrak 1971, Schreiber and Schreiber 1973, Stahlecker 1975, Anderson and Anderson 1976). The Herring and Ring-billed Gull (Larus argentatus and L, dela- warensis) populations of northeastern United States have increased tremendously over the past 75 years (Drury and Kadlec 1974, Lud- wig 1974). Many of these gulls winter in Florida, especially as imma- tures (Southern 1974, Moore 1976, and references therein). Little is known of the status of Laughing Gull (Larus 3tricilla) populations and their movements. In this paper we analyze the CBC's of Florida for the past 33 years as a means of measuring the relative proportion and population status of the three common gull species in Florida: Herring, Ring- billed and Laughing gull. Methods We calculated the index of birds per 10 party hours in the Florida CBC's 1943 through 1975 (Aud. Field Notes: 11-23, Amer. Birds: 25-30) as in Schreiber and Schreiber (1973) with the exception that individual counts were eliminated from analysis if the species under consideration was not seen in a given year. Including party hours for counts in which the species was not seen greatly reduces the index, especially with gulls that are not seen regularly on inland counts. The same index was calculated and graphed for many individual count areas (St. Petersburg, Fort Myers, Sarasota, Coot Bay, Jack- sonville, Daytona, Cocoa Beach) for comparison to each other and the state as a whole. We do not present these results but mention them where appropriate. The low number of counts (5-6) in the 1940's and early 1950's probablymakes these data less reliable. However, since the mid-1 950's the number of counts is sufficient to give a reasonable indication of the population trends of these three wintering species. Florida Field Naturalist Vol. 5 Fall
... MATERIALS AND METHODS In 1990 under appropriate federal and state per-mits, we collected pinc... more ... MATERIALS AND METHODS In 1990 under appropriate federal and state per-mits, we collected pinches of ... in-cluded periodic blind analysis of an aliquot from a large sample of known metalconcentration. ... Geometric mean values, ppb dry wt aFrom Burger and Gochfeld [12] ...
: Johnston Atoll was added to the United States National Wildlife Refuge system in 1926 to protec... more : Johnston Atoll was added to the United States National Wildlife Refuge system in 1926 to protect an important tropical ecosystem and the wildlife that it harbors. Johnston Atoll s ecosystem now includes extensive coral reefs and tropical terrestrial habitats on its four islands. Hundreds of thousands of seabirds inhabit and raise their young on the atoll and hundreds of migrating shorebirds spend their winters there. Extensive coral reefs are home to myriad tropical fish and invertebrates. Its location in the central Pacific also made it an important site for military activities beginning in World War II. Concern about preserving Johnston Atoll's ecosystem prompted the original planners of the Johnston Atoll Chemical Agent Disposal System (JACADS), a demilitarization and incineration project, to arrange for scientists to monitor the birds and marine life of the atoll beginning 6 years before the project began and continuing throughout a total of 20 years of research and monito...
Dispersal and survival rates of adult and juvenile Red-tailed tropicbirds {Phaethon rubricauda) e... more Dispersal and survival rates of adult and juvenile Red-tailed tropicbirds {Phaethon rubricauda) exposed to potential contaminants
Blackwell Publishing, Ltd.Sex-specific foraging behaviour in tropical boobies: does size matter? ... more Blackwell Publishing, Ltd.Sex-specific foraging behaviour in tropical boobies: does size matter? SUE LEWIS,
Philosophical transactions of the Royal Society of London. Series B, Biological sciences, Jan 5, 2018
Telomeres are highly conserved regions of DNA that protect the ends of linear chromosomes. The lo... more Telomeres are highly conserved regions of DNA that protect the ends of linear chromosomes. The loss of telomeres can signal an irreversible change to a cell's state, including cellular senescence. Senescent cells no longer divide and can damage nearby healthy cells, thus potentially placing them at the crossroads of cancer and ageing. While the epidemiology, cellular and molecular biology of telomeres are well studied, a newer field exploring telomere biology in the context of ecology and evolution is just emerging. With work to date focusing on how telomere shortening relates to individual mortality, less is known about how telomeres relate to ageing rates across species. Here, we investigated telomere length in cross-sectional samples from 19 bird species to determine how rates of telomere loss relate to interspecific variation in maximum lifespan. We found that bird species with longer lifespans lose fewer telomeric repeats each year compared with species with shorter lifespa...
Proceedings of the Royal Society B: Biological Sciences, 2010
The Galapagos Islands are renowned for their high degree of endemism. Marine taxa inhabiting the ... more The Galapagos Islands are renowned for their high degree of endemism. Marine taxa inhabiting the archipelago might be expected to be an exception, because of their utilization of pelagic habitats—the dispersal barrier for terrestrial taxa—as foraging grounds. Magnificent frigatebirds ( Fregata magnificens ) have a highly vagile lifestyle and wide geographical distribution around the South and Central American coasts. Given the potentially high levels of gene flow among populations, the species provides a good test of the effectiveness of the Galapagos ecosystem in isolating populations of highly dispersive marine species. We studied patterns of genetic (mitochondrial DNA, microsatellites and nuclear introns) and morphological variation across the distribution of magnificent frigatebirds. Concordant with predictions from life-history traits, we found signatures of extensive gene flow over most of the range, even across the Isthmus of Panama, which is a major barrier to gene flow in o...
Dispersal and survival rates of adult and juvenile Red–tailed tropicbirds (Phaethon rubricauda) e... more Dispersal and survival rates of adult and juvenile Red–tailed tropicbirds (Phaethon rubricauda) exposed to potential contaminants
GULLS WINTERING IN FLORIDA: CHRISTMAS BIRD COUNT ANALYSIS Elizabeth Anne Schreiber and Ralph W. S... more GULLS WINTERING IN FLORIDA: CHRISTMAS BIRD COUNT ANALYSIS Elizabeth Anne Schreiber and Ralph W. Schreiber Introduction Christmas Bird Counts (CBC's) provide a unique data source for determining long term avian population trends over wide geographic areas (Kadlec and Drury 1968, Bystrak 1971, Schreiber and Schreiber 1973, Stahlecker 1975, Anderson and Anderson 1976). The Herring and Ring-billed Gull (Larus argentatus and L, dela- warensis) populations of northeastern United States have increased tremendously over the past 75 years (Drury and Kadlec 1974, Lud- wig 1974). Many of these gulls winter in Florida, especially as imma- tures (Southern 1974, Moore 1976, and references therein). Little is known of the status of Laughing Gull (Larus 3tricilla) populations and their movements. In this paper we analyze the CBC's of Florida for the past 33 years as a means of measuring the relative proportion and population status of the three common gull species in Florida: Herring, Ring- billed and Laughing gull. Methods We calculated the index of birds per 10 party hours in the Florida CBC's 1943 through 1975 (Aud. Field Notes: 11-23, Amer. Birds: 25-30) as in Schreiber and Schreiber (1973) with the exception that individual counts were eliminated from analysis if the species under consideration was not seen in a given year. Including party hours for counts in which the species was not seen greatly reduces the index, especially with gulls that are not seen regularly on inland counts. The same index was calculated and graphed for many individual count areas (St. Petersburg, Fort Myers, Sarasota, Coot Bay, Jack- sonville, Daytona, Cocoa Beach) for comparison to each other and the state as a whole. We do not present these results but mention them where appropriate. The low number of counts (5-6) in the 1940's and early 1950's probablymakes these data less reliable. However, since the mid-1 950's the number of counts is sufficient to give a reasonable indication of the population trends of these three wintering species. Florida Field Naturalist Vol. 5 Fall
... MATERIALS AND METHODS In 1990 under appropriate federal and state per-mits, we collected pinc... more ... MATERIALS AND METHODS In 1990 under appropriate federal and state per-mits, we collected pinches of ... in-cluded periodic blind analysis of an aliquot from a large sample of known metalconcentration. ... Geometric mean values, ppb dry wt aFrom Burger and Gochfeld [12] ...
: Johnston Atoll was added to the United States National Wildlife Refuge system in 1926 to protec... more : Johnston Atoll was added to the United States National Wildlife Refuge system in 1926 to protect an important tropical ecosystem and the wildlife that it harbors. Johnston Atoll s ecosystem now includes extensive coral reefs and tropical terrestrial habitats on its four islands. Hundreds of thousands of seabirds inhabit and raise their young on the atoll and hundreds of migrating shorebirds spend their winters there. Extensive coral reefs are home to myriad tropical fish and invertebrates. Its location in the central Pacific also made it an important site for military activities beginning in World War II. Concern about preserving Johnston Atoll's ecosystem prompted the original planners of the Johnston Atoll Chemical Agent Disposal System (JACADS), a demilitarization and incineration project, to arrange for scientists to monitor the birds and marine life of the atoll beginning 6 years before the project began and continuing throughout a total of 20 years of research and monito...
Dispersal and survival rates of adult and juvenile Red-tailed tropicbirds {Phaethon rubricauda) e... more Dispersal and survival rates of adult and juvenile Red-tailed tropicbirds {Phaethon rubricauda) exposed to potential contaminants
Blackwell Publishing, Ltd.Sex-specific foraging behaviour in tropical boobies: does size matter? ... more Blackwell Publishing, Ltd.Sex-specific foraging behaviour in tropical boobies: does size matter? SUE LEWIS,
Philosophical transactions of the Royal Society of London. Series B, Biological sciences, Jan 5, 2018
Telomeres are highly conserved regions of DNA that protect the ends of linear chromosomes. The lo... more Telomeres are highly conserved regions of DNA that protect the ends of linear chromosomes. The loss of telomeres can signal an irreversible change to a cell's state, including cellular senescence. Senescent cells no longer divide and can damage nearby healthy cells, thus potentially placing them at the crossroads of cancer and ageing. While the epidemiology, cellular and molecular biology of telomeres are well studied, a newer field exploring telomere biology in the context of ecology and evolution is just emerging. With work to date focusing on how telomere shortening relates to individual mortality, less is known about how telomeres relate to ageing rates across species. Here, we investigated telomere length in cross-sectional samples from 19 bird species to determine how rates of telomere loss relate to interspecific variation in maximum lifespan. We found that bird species with longer lifespans lose fewer telomeric repeats each year compared with species with shorter lifespa...
Proceedings of the Royal Society B: Biological Sciences, 2010
The Galapagos Islands are renowned for their high degree of endemism. Marine taxa inhabiting the ... more The Galapagos Islands are renowned for their high degree of endemism. Marine taxa inhabiting the archipelago might be expected to be an exception, because of their utilization of pelagic habitats—the dispersal barrier for terrestrial taxa—as foraging grounds. Magnificent frigatebirds ( Fregata magnificens ) have a highly vagile lifestyle and wide geographical distribution around the South and Central American coasts. Given the potentially high levels of gene flow among populations, the species provides a good test of the effectiveness of the Galapagos ecosystem in isolating populations of highly dispersive marine species. We studied patterns of genetic (mitochondrial DNA, microsatellites and nuclear introns) and morphological variation across the distribution of magnificent frigatebirds. Concordant with predictions from life-history traits, we found signatures of extensive gene flow over most of the range, even across the Isthmus of Panama, which is a major barrier to gene flow in o...
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