Effects of mass capture on survival of greater white‐fronted geese in Alaska

Abstract

Mass capture of flightless geese during the summer is a common trapping technique to obtain large numbers of individuals for research and marking, but few studies have assessed the impacts of this method on the survival of after‐hatch‐year geese. We evaluated the effects of holding time and captured flock size on the survival of >26,000 subadult (second yr) and adult (≥third yr) greater white‐fronted geese (Anser albifrons frontalis) banded in Alaska, USA, 1999–2017. We constructed models with and without capture effects to analyze our band‐recovery data and used Akaike's Information Criterion to rank our model set. Models that included both capture‐related variables ranked highest. Longer individual holding times negatively affected survival during the first year after banding, and effects were greatest during the earliest years of our study when holding times were generally longer and protocols to minimize negative capture effects were less refined. There was a positive relationship between survival and captured flock size. We suggest practitioners reduce holding times of geese during mass captures to the extent practicable and continually evaluate and refine their methods to minimize negative capture effects.