Individual heterogeneity in fitness in a long‐lived herbivore ...

• Main Authors: Lohman, Madeleine, Riecke, Thomas, Williams, Perry, Sedinger, James, Lohman, Madeleine G., Riecke, Thomas V., Williams, Perry J., Sedinger, James S.
• Format: Dataset
• Language: English
• Published: Dryad 2021
• Subjects: FOS: Natural sciences; Branta bernicla nigricans; Bayesian mark-recapture; capture-mark-recapture; initiation date; lay date; Brant; Yukon; Branta bernicla; Kuskokwim; Alaska
• Online Access: https://dx.doi.org/10.5061/dryad.z08kprrdg; https://datadryad.org/stash/dataset/doi:10.5061/dryad.z08kprrdg

Heterogeneity in the intrinsic quality and nutritional condition of individuals affects reproductive success and consequently fitness. Black brant (Branta bernicla nigricans) are long-lived, migratory, specialist herbivores. Long migratory pathways and short summer breeding seasons constrain the time and energy available for reproduction, thus magnifying life-history trade-offs. These constraints, combined with long lifespans and trade-offs between current and future reproductive value, provide a model system to examine the role of individual heterogeneity in driving life-history strategies and individual heterogeneity in fitness. We used hierarchical Bayesian models to examine reproductive trade-offs, modeling the relationships between within-year measures of reproductive energy allocation and among-year demographic rates of individual females breeding on the Yukon-Kuskokwim Delta, Alaska using capture-recapture and reproductive data from 1988 to 2014. We generally found that annual survival tended to be ... : We collected data at the Tutakoke River Colony (61.25◦N, 165.61◦W) and related brood rearing areas on the Yukon-Kuskokwim Delta near the mouth of the Kashunuk River from 1988-2014. May - June, nests were monitored every four days throughout nest initiation, and again before and during hatch. Observers recorded clutch sizes and initiation dates of nests during this time. Incubation time is generally 23-29 days, varying with laying date and clutch size. Thus, we back-calculated initiation dates for hatched nests using mean incubation period (~26 days). Mid-late July, adult and juvenile brant were herded into pens and marked with a unique U.S. Geological Survey metal band and an alpha-numerically coded plastic band during the adult wing-molt. Resighting occured throughout the breeding season (May-late July). We included capture-history data only for marked adult females (n = 7,845). We included data on mean lifetime clutch sizes for 6,256 individuals (µ = 3.83; SD = 1.129) and mean initiation dates for 5,207 ...