Survival of juvenile black brant during brood rearing

Journal of Wildlife Management
By: , and 

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Abstract

Survival of young is an important and poorly understood component of waterfowl productivity. We estimated survival of black brant (Branta bernicla nigricans) goslings during summers 1987-89 on the Yukon-Kuskokwim Delta, Alaska, to determine timing and magnitude of gosling mortality and to compare methods of estimating gosling survival. Eighty-two percent of radio-tagged adult females (n = 61) fledged ≥1 gosling (brood success). We estimated survival of goslings within broods by 3 methods: (1) changes in mean brood size through time, (2) observation of goslings associated with marked adults, and (3) age ratios of brant captured in banding drives. Estimates of gosling survival within successful broods averaged 81% and ranged from 66 to 92%. Combining brood success and gosling survival within successful broods yielded estimates of overall gosling survival that averaged 68%, ranging from 79% in 1987 to 56% in 1989. Eighty-two percent of gosling mortality occurred in the first 15 days. Estimates of survival on the basis of age ratios of birds captured in banding drives are biased low. Our estimates of average gosling survival are higher than reported for other species of geese.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Survival of juvenile black brant during brood rearing
Series title Journal of Wildlife Management
DOI 10.2307/3802451
Volume 59
Issue 3
Year Published 1995
Language English
Publisher Wiley
Contributing office(s) Alaska Science Center
Description 9 p.
First page 455
Last page 463
Country United States
State Alaska
Other Geospatial Yukon-Kuskokwim Delta