Life-History Implications of Large-Scale Spatial Variation in Adult Survival of Black Brant (Branta bernicla nigricans)
Sedinger JS, Chelgren ND, Lindberg MS, Obritchkewitch T, Kirk MT, Martin P, Anderson BA, Ward DH. 2002. Life-History Implications of Large-Scale Spatial Variation in Adult Survival of Black Brant (Branta bernicla nigricans). The Auk. 119(2):510-515
We used capture-recapture methods to estimate adult survival rates for adult female Black Brant (Branta bernicla nigricans; hereafter "brant") from three colonies in Alaska, two on the Yukon-Kuskokwim Delta, and one on Alaska's Arctic coast. Costs of migration and reproductive effort varied among those colonies, enabling us to examine variation in survival in relation to variation in these other variables. We used the Barker model in program MARK to estimate true annual survival for brant from the three colonies. Models allowing for spatial variation in survival were among the most parsimonious models but were indistinguishable from a model with no spatial variation. Point estimates of annual survival were slightly higher for brant from the Arctic (0.90 + 0.036) than for brant from either Tutakoke River (0.85 ? 0.004) or Kokechik Bay (0.86 ? 0.011). Thus, our survival estimates do not support a hypothesis that the cost of longer migrations or harvest experienced by brant from the Arctic reduced their annual survival relative to brant from the Yukon-Kuskokwim Delta. Spatial variation in survival provides weak support for life-history theory because brant from the region with lower reproductive investment had slightly higher survival.
- Type
- Journal Article
- Authors
- Sedinger, J; Chelgren, N; Lindberg, M; Obritchkewitch, T; Kirk, M; Martin, P; Anderson, B; Ward, D
- Units
- ARCN , BELA , CAKR , GAAR , KOVA , NOAT
- Keywords
- Arctic, Birds, Brant, Breeding Biology, Geese, Mortality, North Slope, population demography, Population Ecology, Population Trends, Survival, Waterfowl, Yukon-Kuskokwim Delta