Meeting Abstract
A common assumption underlying many biological studies is that the data we collect from a subset of individuals are representative of the population of interest. However, in studies of free-ranging animals, capture method might skew samples towards individuals with specific morphological, physiological, and/or behavioral traits. For example, in studies of free-ranging birds, bolder individuals might be more likely to enter nets and traps commonly used in capture. We sought to explore this possible bias by comparing individual birds sampled using two different capture techniques. We caught free-ranging black-capped chickadees (Poecile atricapillus) using Potter traps baited with seed and mist nets paired with an audio stimulus (chickadee mobbing calls) and determined sex, body condition, baseline and stress induced glucocorticoid levels, behavioral response to a novel object, and behavioral response to a predator. Differences between individuals captured using the two methods have implications for the design of studies aimed at understanding the physiology or behavior of free-ranging animals, as well as laboratory-based studies when genetic stock is derived from wild caught individuals. Understanding the potential for capture method induced bias will allow for more appropriate and informative sampling of populations.
