The Experts below are selected from a list of 1743 Experts worldwide ranked by ideXlab platform
W.g. Warren - One of the best experts on this subject based on the ideXlab platform.
-
Pup production and population growth of hooded seals (Cystophora cristata) near Newfoundland, Canada
Canadian Journal of Fisheries and Aquatic Sciences, 1997Co-Authors: G. B. Stenson, R.a. Myers, W.g. WarrenAbstract:Pup production of hooded seals (Cystophora cristata) in two Whelping concentrations along the northeast coast of Newfoundland (the "Front") during March 1990 was estimated using systematic visual surveys. In addition, independent estimates of production in one of the concentrations and the number of pups born outside the Whelping concentrations were obtained from photographic surveys. Photographic estimates were adjusted for incorrectly identified pups by comparing black and white photographs with ultraviolet imagery. Estimates were also corrected for pups that had yet to be born at the time of the survey or had left the ice using distinct age-related developmental stages. Approximately 91\% of the pups born in the first Whelping concentration, and 92\% born in the second, were present during the surveys. Based on a combination of visual and photographic surveys, the corrected pup production in these concentrations was estimated to be 49 600 (SE = 2700). Photographic surveys resulted in an estimate of 33 500 (SE = 12 400) pups born outside the Whelping patches, although this estimate could not be corrected for the abscence of pups due to the temporal distribution of births. Thus, total pup production was estimated to be 83 100 (SE = 12 700). Although nominally greater, this estimate is not statistically different from a comparable estimate of hooded seal pup production in 1984
-
Pup production of hooded seals (Cystophora cristata) in the Northwest Atlantic
Nafo Scientific Council Studies, 1996Co-Authors: Garry B. Stenson, R.a. Myers, W.g. WarrenAbstract:Pup production of hooded seals (Cystophora cristata) in two Whelping concentrations along the northeast coast of Newfoundland (the 'Front') during March 1990 was estimated using systematic visual surveys. In addition, independent estimates of production in one of the concentrations and the number of pups born outside the Whelping concentrations were obtained from photographic surveys. Photographic estimates were corrected for incorrectly identified pups by comparing black and white photographs with ultra-violet imagery. Estimates were also corrected for pups absent from the ice at the time of the survey using distinct age-related developmental stages. Approximately 91% of the pups born in the first Whelping concentration, and 92% born in the second, were present during the surveys. Based on visual surveys, the corrected pup production in these patches was estimated to be 48 684 (SE = 2 747). Photographic surveys resulted in an estimate of 33 498 (SE = 12 450) pups born outside of the Whelping patches, although this estimate could not be corrected for the absence of pups due to the temporal distribution of births. Thus, total pup production was estimated to be 82 182 (SE = 12 636). Comparison with estimates made in the mid-1980s suggest that pup production may have increased although they are not statistically different due to the imprecise nature of the estimates.
G. B. Stenson - One of the best experts on this subject based on the ideXlab platform.
-
DNA sequence analysis identifies genetically distinguishable populations of harp seals (Pagophilus groenlandicus) in the Northwest and Northeast Atlantic
Marine Biology, 2000Co-Authors: E. A. Perry, G. B. Stenson, Sylvia E. Bartlett, William S. Davidson, Steven M. CarrAbstract:Harp seals (Pagophilus groenlandicus Erxleben, 1777) comprise three populations based upon Whelping areas in the Greenland Sea, White Sea, and Northwest Atlantic. The last comprises two subpopulations, one Whelping in the Gulf of St. Lawrence (“Gulf ”) and one on the pack ice of the southern Labrador/northern Newfoundland coastal shelf (“Front”). A total of 40 female seals from the four Whelping areas were collected during the 1990 and 1992 Whelping seasons. DNA sequence variation was examined in a 307 bp region of the mitochondrial cytochrome b gene. Eleven variable nucleotide positions defined 13 genotypes: a significant fraction of the genotypic variance (F ST=0.12, or 0.09 as measured by Weir's coancestry coefficient θ) is attributable to differentiation between Northwest and Northeast Atlantic populations. There was no significant differentiation between the two Whelping areas in the Northwest Atlantic, or between the Greenland Sea and White Sea. These findings suggest significant reproductive isolation exists between trans-Atlantic breeding populations.
-
Pup production and population growth of hooded seals (Cystophora cristata) near Newfoundland, Canada
Canadian Journal of Fisheries and Aquatic Sciences, 1997Co-Authors: G. B. Stenson, R.a. Myers, W.g. WarrenAbstract:Pup production of hooded seals (Cystophora cristata) in two Whelping concentrations along the northeast coast of Newfoundland (the "Front") during March 1990 was estimated using systematic visual surveys. In addition, independent estimates of production in one of the concentrations and the number of pups born outside the Whelping concentrations were obtained from photographic surveys. Photographic estimates were adjusted for incorrectly identified pups by comparing black and white photographs with ultraviolet imagery. Estimates were also corrected for pups that had yet to be born at the time of the survey or had left the ice using distinct age-related developmental stages. Approximately 91\% of the pups born in the first Whelping concentration, and 92\% born in the second, were present during the surveys. Based on a combination of visual and photographic surveys, the corrected pup production in these concentrations was estimated to be 49 600 (SE = 2700). Photographic surveys resulted in an estimate of 33 500 (SE = 12 400) pups born outside the Whelping patches, although this estimate could not be corrected for the abscence of pups due to the temporal distribution of births. Thus, total pup production was estimated to be 83 100 (SE = 12 700). Although nominally greater, this estimate is not statistically different from a comparable estimate of hooded seal pup production in 1984
R.a. Myers - One of the best experts on this subject based on the ideXlab platform.
-
Pup production and population growth of hooded seals (Cystophora cristata) near Newfoundland, Canada
Canadian Journal of Fisheries and Aquatic Sciences, 1997Co-Authors: G. B. Stenson, R.a. Myers, W.g. WarrenAbstract:Pup production of hooded seals (Cystophora cristata) in two Whelping concentrations along the northeast coast of Newfoundland (the "Front") during March 1990 was estimated using systematic visual surveys. In addition, independent estimates of production in one of the concentrations and the number of pups born outside the Whelping concentrations were obtained from photographic surveys. Photographic estimates were adjusted for incorrectly identified pups by comparing black and white photographs with ultraviolet imagery. Estimates were also corrected for pups that had yet to be born at the time of the survey or had left the ice using distinct age-related developmental stages. Approximately 91\% of the pups born in the first Whelping concentration, and 92\% born in the second, were present during the surveys. Based on a combination of visual and photographic surveys, the corrected pup production in these concentrations was estimated to be 49 600 (SE = 2700). Photographic surveys resulted in an estimate of 33 500 (SE = 12 400) pups born outside the Whelping patches, although this estimate could not be corrected for the abscence of pups due to the temporal distribution of births. Thus, total pup production was estimated to be 83 100 (SE = 12 700). Although nominally greater, this estimate is not statistically different from a comparable estimate of hooded seal pup production in 1984
-
Pup production of hooded seals (Cystophora cristata) in the Northwest Atlantic
Nafo Scientific Council Studies, 1996Co-Authors: Garry B. Stenson, R.a. Myers, W.g. WarrenAbstract:Pup production of hooded seals (Cystophora cristata) in two Whelping concentrations along the northeast coast of Newfoundland (the 'Front') during March 1990 was estimated using systematic visual surveys. In addition, independent estimates of production in one of the concentrations and the number of pups born outside the Whelping concentrations were obtained from photographic surveys. Photographic estimates were corrected for incorrectly identified pups by comparing black and white photographs with ultra-violet imagery. Estimates were also corrected for pups absent from the ice at the time of the survey using distinct age-related developmental stages. Approximately 91% of the pups born in the first Whelping concentration, and 92% born in the second, were present during the surveys. Based on visual surveys, the corrected pup production in these patches was estimated to be 48 684 (SE = 2 747). Photographic surveys resulted in an estimate of 33 498 (SE = 12 450) pups born outside of the Whelping patches, although this estimate could not be corrected for the absence of pups due to the temporal distribution of births. Thus, total pup production was estimated to be 82 182 (SE = 12 636). Comparison with estimates made in the mid-1980s suggest that pup production may have increased although they are not statistically different due to the imprecise nature of the estimates.
Arie Nadler - One of the best experts on this subject based on the ideXlab platform.
-
inter group helping relations as power relations maintaining or challenging social dominance between groups through helping
Journal of Social Issues, 2002Co-Authors: Arie NadlerAbstract:The article presents a model which proposes that groups may establish or challenge dominance through helping. It begins by noting the centrality of inequality in helping and inter–group relations. The implications of this to affirmative action programs are noted. Following this, a model of inter–group helping relations is proposed. It suggests that when the high status group provides to the low status group dependency oriented help, it may do so in order to establish dominance. The willing receptivity of the low status group may indicate its acceptance of the inequality, and lack of receptivity for such help may be motivated by the desire to achieve social equality. Empirical findings that are relevant to this analysis are presented in studies using Israeli students as research participants.
-
Inter–Group Helping Relations as Power Relations: Maintaining or Challenging Social Dominance Between Groups Through Helping
Journal of Social Issues, 2002Co-Authors: Arie NadlerAbstract:The article presents a model which proposes that groups may establish or challenge dominance through helping. It begins by noting the centrality of inequality in helping and inter–group relations. The implications of this to affirmative action programs are noted. Following this, a model of inter–group helping relations is proposed. It suggests that when the high status group provides to the low status group dependency oriented help, it may do so in order to establish dominance. The willing receptivity of the low status group may indicate its acceptance of the inequality, and lack of receptivity for such help may be motivated by the desire to achieve social equality. Empirical findings that are relevant to this analysis are presented in studies using Israeli students as research participants.
Steven M. Carr - One of the best experts on this subject based on the ideXlab platform.
-
DNA sequence analysis identifies genetically distinguishable populations of harp seals (Pagophilus groenlandicus) in the Northwest and Northeast Atlantic
Marine Biology, 2000Co-Authors: E. A. Perry, G. B. Stenson, Sylvia E. Bartlett, William S. Davidson, Steven M. CarrAbstract:Harp seals (Pagophilus groenlandicus Erxleben, 1777) comprise three populations based upon Whelping areas in the Greenland Sea, White Sea, and Northwest Atlantic. The last comprises two subpopulations, one Whelping in the Gulf of St. Lawrence (“Gulf ”) and one on the pack ice of the southern Labrador/northern Newfoundland coastal shelf (“Front”). A total of 40 female seals from the four Whelping areas were collected during the 1990 and 1992 Whelping seasons. DNA sequence variation was examined in a 307 bp region of the mitochondrial cytochrome b gene. Eleven variable nucleotide positions defined 13 genotypes: a significant fraction of the genotypic variance (F ST=0.12, or 0.09 as measured by Weir's coancestry coefficient θ) is attributable to differentiation between Northwest and Northeast Atlantic populations. There was no significant differentiation between the two Whelping areas in the Northwest Atlantic, or between the Greenland Sea and White Sea. These findings suggest significant reproductive isolation exists between trans-Atlantic breeding populations.
