The Experts below are selected from a list of 6120 Experts worldwide ranked by ideXlab platform
Gerald Heckel - One of the best experts on this subject based on the ideXlab platform.
-
breeding site fidelity and winter admixture in a long distance migrant the tufted duck aythya fuligula
2012Co-Authors: Irene Keller, Gerald HeckelAbstract:Long-distance migrants are, by definition, highly mobile but it is poorly understood if this leads to high rates of gene flow and an essentially panmictic global population structure. Genetic divergence in migratory species could be promoted, for example, by fidelity to distinct migratory pathways. In this study, we investigate the population genetic structure of tufted duck (Aythya fuligula), a long-distance migrant with a largely continuous breeding distribution across Eurasia. Distinct, longitudinally oriented flyways have been postulated based on geographically disjunct Wintering areas and are supported by evidence from ringing data. We generated sequences of the mitochondrial control region and multi-locus microsatellite genotypes for several hundreds of samples from the European and Asian breeding and Wintering Grounds including some individuals infected with highly pathogenic avian influenza virus H5N1. Significant differentiation between breeding sites was observed for both marker types, but FST values were approximately 10 times higher for maternally inherited mitochondrial DNA than for biparentally transmitted nuclear markers. The genetic differentiation between the postulated European and Asian flyways was similar to that observed within continents and, in general, genetic divergence was not associated with geographic distance. Neither marker type showed evidence of genetic substructure among aggregations on the European Wintering Grounds. Our results suggest some breeding site fidelity, especially in females, but extensive population admixture on the Wintering Grounds. Several scenarios may explain the observed lack of genetic divergence between Europe and Asia including non-equilibrium conditions following a recent range expansion or contemporary gene flow across the postulated migratory divides.
-
breeding site fidelity and winter admixture in a long distance migrant the tufted duck aythya fuligula
2012Co-Authors: Irene Keller, Gerald HeckelAbstract:Long-distance migrants are, by definition, highly mobile but it is poorly understood if this leads to high rates of gene flow and an essentially panmictic global population structure. Genetic divergence in migratory species could be promoted, for example, by fidelity to distinct migratory pathways. In this study, we investigate the population genetic structure of tufted duck (Aythya fuligula), a long-distance migrant with a largely continuous breeding distribution across Eurasia. Distinct, longitudinally oriented flyways have been postulated based on geographically disjunct Wintering areas and are supported by evidence from ringing data. We generated sequences of the mitochondrial control region and multi-locus microsatellite genotypes for several hundreds of samples from the European and Asian breeding and Wintering Grounds including some individuals infected with highly pathogenic avian influenza virus H5N1. Significant differentiation between breeding sites was observed for both marker types, but FST values were approximately 10 times higher for maternally inherited mitochondrial DNA than for biparentally transmitted nuclear markers. The genetic differentiation between the postulated European and Asian flyways was similar to that observed within continents and, in general, genetic divergence was not associated with geographic distance. Neither marker type showed evidence of genetic substructure among aggregations on the European Wintering Grounds. Our results suggest some breeding site fidelity, especially in females, but extensive population admixture on the Wintering Grounds. Several scenarios may explain the observed lack of genetic divergence between Europe and Asia including non-equilibrium conditions following a recent range expansion or contemporary gene flow across the postulated migratory divides.
Emma L. Carroll - One of the best experts on this subject based on the ideXlab platform.
-
Satellite derived offshore migratory movements of southern right whales (Eubalaena australis) from Australian and New Zealand Wintering Grounds.
2020Co-Authors: Alice I. Mackay, John Bannister, C. Scott Baker, Frédéric Bailleul, Emma L. Carroll, Virginia Andrews-goff, Laura J. Boren, Krisa Carlyon, David Donnelly, Michael C. DoubleAbstract:Southern right whales (Eubalaena australis) migrate between Austral-winter calving and socialising Grounds to offshore mid- to high latitude Austral-summer feeding Grounds. In Australasia, winter calving Grounds used by southern right whales extend from Western Australia across southern Australia to the New Zealand sub-Antarctic Islands. During the Austral-summer these whales are thought to migrate away from coastal waters to feed, but the location of these feeding Grounds is only inferred from historical whaling data. We present new information on the satellite derived offshore migratory movements of six southern right whales from Australasian Wintering Grounds. Two whales were tagged at the Auckland Islands, New Zealand, and the remaining four at Australian Wintering Grounds, one at Pirates Bay, Tasmania, and three at Head of Bight, South Australia. The six whales were tracked for an average of 78.5 days (range: 29 to 150) with average individual distance of 38 km per day (range: 20 to 61 km). The length of individually derived tracks ranged from 645-6,381 km. Three likely foraging Grounds were identified: south-west Western Australia, the Subtropical Front, and Antarctic waters, with the Subtropical Front appearing to be a feeding ground for both New Zealand and Australian southern right whales. In contrast, the individual tagged in Tasmania, from a sub-population that is not showing evidence of post-whaling recovery, displayed a distinct movement pattern to much higher latitude waters, potentially reflecting a different foraging strategy. Variable population growth rates between Wintering Grounds in Australasia could reflect fidelity to different quality feeding Grounds. Unlike some species of baleen whale populations that show movement along migratory corridors, the new satellite tracking data presented here indicate variability in the migratory pathways taken by southern right whales from Australia and New Zealand, as well as differences in potential Austral summer foraging Grounds.
-
Genetic Diversity and Connectivity of Southern Right Whales (Eubalaena australis) Found in the Brazil and Chile-Peru Wintering Grounds and the South Georgia (Islas Georgias del Sur) Feeding Ground.
2020Co-Authors: Emma L. Carroll, C. Scott Baker, Paulo Henrique Ott, Els Vermeulen, Louise F Mcmillan, Bárbara Galletti Vernazzani, Petra Neveceralova, Oscar E. Gaggiotti, Artur Andriolo, Connor C. G. BamfordAbstract:As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (nnew) and published (npub) mitochondrial (mtDNA) and microsatellite genetic data from all major Wintering Grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding Grounds. Specifically, we include data from Argentina (npub mtDNA/microsatellite = 208/46), Brazil (nnew mtDNA/microsatellite = 50/50), South Africa (nnew mtDNA/microsatellite = 66/77, npub mtDNA/microsatellite = 350/47), Chile-Peru (nnew mtDNA/microsatellite = 1/1), the Indo-Pacific (npub mtDNA/microsatellite = 769/126), and SG (npub mtDNA/microsatellite = 8/0, nnew mtDNA/microsatellite = 3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG, and Chile-Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of 1 genetically identified individual between the South American Grounds. The single sample from Chile-Peru had an mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic and were more similar to the South American than the South African Wintering Grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile-Peru.
-
reestablishment of former Wintering Grounds by new zealand southern right whales
2014Co-Authors: Emma L. Carroll, Nathalie J. Patenaude, William Rayment, Alana Alexander, Scott C Baker, Debbie Steel, Rochelle Constantine, Rosalind Cole, Laura J. BorenAbstract:Historically, the range of the southern right whale (SRW) included winter calving Grounds around the North and South Islands (mainland) of New Zealand (NZ) and in the NZ subantarctic Auckland and Campbell Islands. Due to extensive whaling in the 19th and 20th centuries, no SRW was seen around mainland NZ for nearly four decades (1928–1963). Here we present evidence for the regular use of the mainland NZ Wintering ground, presumably from a remnant population that persisted in the NZ subantarctic Auckland and Campbell Islands. SRWs have been sighted every year around mainland NZ since 1988, with 125 sightings during the focus of this work: from 2003 to 2010. There were 28 cow-calf pairs sighted around mainland NZ from 2003 to 2010, compared with 11 sightings from 1991 to 2002. Furthermore, two females, identified by DNA profiles, were sighted with calves around mainland at 4 yr intervals: the first evidence of female site fidelity to the mainland NZ calving ground. Individual identification from photographs of natural markings and DNA profiles provided information on within-year movements and residency around the mainland, and further evidence for exchange between the mainland and subantarctic Wintering Grounds. Despite these promising signs, the distribution of NZ SRWs remains primarily concentrated in the NZ subantarctic.
C. Scott Baker - One of the best experts on this subject based on the ideXlab platform.
-
Satellite derived offshore migratory movements of southern right whales (Eubalaena australis) from Australian and New Zealand Wintering Grounds.
2020Co-Authors: Alice I. Mackay, John Bannister, C. Scott Baker, Frédéric Bailleul, Emma L. Carroll, Virginia Andrews-goff, Laura J. Boren, Krisa Carlyon, David Donnelly, Michael C. DoubleAbstract:Southern right whales (Eubalaena australis) migrate between Austral-winter calving and socialising Grounds to offshore mid- to high latitude Austral-summer feeding Grounds. In Australasia, winter calving Grounds used by southern right whales extend from Western Australia across southern Australia to the New Zealand sub-Antarctic Islands. During the Austral-summer these whales are thought to migrate away from coastal waters to feed, but the location of these feeding Grounds is only inferred from historical whaling data. We present new information on the satellite derived offshore migratory movements of six southern right whales from Australasian Wintering Grounds. Two whales were tagged at the Auckland Islands, New Zealand, and the remaining four at Australian Wintering Grounds, one at Pirates Bay, Tasmania, and three at Head of Bight, South Australia. The six whales were tracked for an average of 78.5 days (range: 29 to 150) with average individual distance of 38 km per day (range: 20 to 61 km). The length of individually derived tracks ranged from 645-6,381 km. Three likely foraging Grounds were identified: south-west Western Australia, the Subtropical Front, and Antarctic waters, with the Subtropical Front appearing to be a feeding ground for both New Zealand and Australian southern right whales. In contrast, the individual tagged in Tasmania, from a sub-population that is not showing evidence of post-whaling recovery, displayed a distinct movement pattern to much higher latitude waters, potentially reflecting a different foraging strategy. Variable population growth rates between Wintering Grounds in Australasia could reflect fidelity to different quality feeding Grounds. Unlike some species of baleen whale populations that show movement along migratory corridors, the new satellite tracking data presented here indicate variability in the migratory pathways taken by southern right whales from Australia and New Zealand, as well as differences in potential Austral summer foraging Grounds.
-
Genetic Diversity and Connectivity of Southern Right Whales (Eubalaena australis) Found in the Brazil and Chile-Peru Wintering Grounds and the South Georgia (Islas Georgias del Sur) Feeding Ground.
2020Co-Authors: Emma L. Carroll, C. Scott Baker, Paulo Henrique Ott, Els Vermeulen, Louise F Mcmillan, Bárbara Galletti Vernazzani, Petra Neveceralova, Oscar E. Gaggiotti, Artur Andriolo, Connor C. G. BamfordAbstract:As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (nnew) and published (npub) mitochondrial (mtDNA) and microsatellite genetic data from all major Wintering Grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding Grounds. Specifically, we include data from Argentina (npub mtDNA/microsatellite = 208/46), Brazil (nnew mtDNA/microsatellite = 50/50), South Africa (nnew mtDNA/microsatellite = 66/77, npub mtDNA/microsatellite = 350/47), Chile-Peru (nnew mtDNA/microsatellite = 1/1), the Indo-Pacific (npub mtDNA/microsatellite = 769/126), and SG (npub mtDNA/microsatellite = 8/0, nnew mtDNA/microsatellite = 3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG, and Chile-Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of 1 genetically identified individual between the South American Grounds. The single sample from Chile-Peru had an mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic and were more similar to the South American than the South African Wintering Grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile-Peru.
-
Distribution and diversity of mtDNA lineages among southern right whales (Eubalaena australis) from Australia and New Zealand
1999Co-Authors: C. Scott Baker, Nathalie J. Patenaude, J. L. Bannister, J. Robins, Hidehiro KatoAbstract:Using a biopsy dart system, samples of skin tissue were collected from southern right whales (Eubalaena australis) in 1995 on two Wintering Grounds, southwest Australia (n = 20) and the Auckland Islands of New Zealand (n = 20); and on offshore feeding Grounds at Latitudes 40 to 43°, south of Western Australia (n = 5). A variable section of the mitochondrial DNA control-region (289 nucleotides) was amplified and sequenced from these 45 individuals (21 males, 20 females and 4 of unknown sex), distinguishing a total of seven unique sequences (i.e. mtDNA haplotypes). Two haplotypes were found on both Wintering Grounds (including a common type representing 45% of each sample), and five types were unique to only one Wintering ground. An analysis of variance adapted for molecular information revealed significant genetic differentiation between the two Wintering Grounds (p = 0.017). The feeding-ground sample was too small for statistical comparison with the Wintering Grounds, but included two haplotypes found only in the Auckland Islands as well as the common haplotype found on both Wintering Grounds. The nucleotide diversity and differentiation of mtDNA among the right whales was similar to that among humpback whales (Megaptera novaeangliae) from the same regions (Baker et al. 1998), but haplotype diversity was significantly reduced, perhaps as a result of more intensive hunting during the last century and continued illegal hunting during this century.
Connor C. G. Bamford - One of the best experts on this subject based on the ideXlab platform.
-
Genetic Diversity and Connectivity of Southern Right Whales (Eubalaena australis) Found in the Brazil and Chile-Peru Wintering Grounds and the South Georgia (Islas Georgias del Sur) Feeding Ground.
2020Co-Authors: Emma L. Carroll, C. Scott Baker, Paulo Henrique Ott, Els Vermeulen, Louise F Mcmillan, Bárbara Galletti Vernazzani, Petra Neveceralova, Oscar E. Gaggiotti, Artur Andriolo, Connor C. G. BamfordAbstract:As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (nnew) and published (npub) mitochondrial (mtDNA) and microsatellite genetic data from all major Wintering Grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding Grounds. Specifically, we include data from Argentina (npub mtDNA/microsatellite = 208/46), Brazil (nnew mtDNA/microsatellite = 50/50), South Africa (nnew mtDNA/microsatellite = 66/77, npub mtDNA/microsatellite = 350/47), Chile-Peru (nnew mtDNA/microsatellite = 1/1), the Indo-Pacific (npub mtDNA/microsatellite = 769/126), and SG (npub mtDNA/microsatellite = 8/0, nnew mtDNA/microsatellite = 3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG, and Chile-Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of 1 genetically identified individual between the South American Grounds. The single sample from Chile-Peru had an mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic and were more similar to the South American than the South African Wintering Grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile-Peru.
Irene Keller - One of the best experts on this subject based on the ideXlab platform.
-
breeding site fidelity and winter admixture in a long distance migrant the tufted duck aythya fuligula
2012Co-Authors: Irene Keller, Gerald HeckelAbstract:Long-distance migrants are, by definition, highly mobile but it is poorly understood if this leads to high rates of gene flow and an essentially panmictic global population structure. Genetic divergence in migratory species could be promoted, for example, by fidelity to distinct migratory pathways. In this study, we investigate the population genetic structure of tufted duck (Aythya fuligula), a long-distance migrant with a largely continuous breeding distribution across Eurasia. Distinct, longitudinally oriented flyways have been postulated based on geographically disjunct Wintering areas and are supported by evidence from ringing data. We generated sequences of the mitochondrial control region and multi-locus microsatellite genotypes for several hundreds of samples from the European and Asian breeding and Wintering Grounds including some individuals infected with highly pathogenic avian influenza virus H5N1. Significant differentiation between breeding sites was observed for both marker types, but FST values were approximately 10 times higher for maternally inherited mitochondrial DNA than for biparentally transmitted nuclear markers. The genetic differentiation between the postulated European and Asian flyways was similar to that observed within continents and, in general, genetic divergence was not associated with geographic distance. Neither marker type showed evidence of genetic substructure among aggregations on the European Wintering Grounds. Our results suggest some breeding site fidelity, especially in females, but extensive population admixture on the Wintering Grounds. Several scenarios may explain the observed lack of genetic divergence between Europe and Asia including non-equilibrium conditions following a recent range expansion or contemporary gene flow across the postulated migratory divides.
-
breeding site fidelity and winter admixture in a long distance migrant the tufted duck aythya fuligula
2012Co-Authors: Irene Keller, Gerald HeckelAbstract:Long-distance migrants are, by definition, highly mobile but it is poorly understood if this leads to high rates of gene flow and an essentially panmictic global population structure. Genetic divergence in migratory species could be promoted, for example, by fidelity to distinct migratory pathways. In this study, we investigate the population genetic structure of tufted duck (Aythya fuligula), a long-distance migrant with a largely continuous breeding distribution across Eurasia. Distinct, longitudinally oriented flyways have been postulated based on geographically disjunct Wintering areas and are supported by evidence from ringing data. We generated sequences of the mitochondrial control region and multi-locus microsatellite genotypes for several hundreds of samples from the European and Asian breeding and Wintering Grounds including some individuals infected with highly pathogenic avian influenza virus H5N1. Significant differentiation between breeding sites was observed for both marker types, but FST values were approximately 10 times higher for maternally inherited mitochondrial DNA than for biparentally transmitted nuclear markers. The genetic differentiation between the postulated European and Asian flyways was similar to that observed within continents and, in general, genetic divergence was not associated with geographic distance. Neither marker type showed evidence of genetic substructure among aggregations on the European Wintering Grounds. Our results suggest some breeding site fidelity, especially in females, but extensive population admixture on the Wintering Grounds. Several scenarios may explain the observed lack of genetic divergence between Europe and Asia including non-equilibrium conditions following a recent range expansion or contemporary gene flow across the postulated migratory divides.
