Escape Behaviour and Use of Cover by Young-of-the-Year Brook Trout, Salvelinus fontinalis

Abstract
The distance between young-of-the-year (YOY) brook trout (Salvelinus fontinalis) and an approaching observer when the trout first fled (reactive distance) was significantly shorter in areas of high cover than in areas of low cover. Reactive distance was negatively correlated with foraging rate in one stream but not in another. These results provide some support for a recent economic model of escape behaviour. Three measures of willingness to take risks while foraging, reactive distance, latency to forage after a disturbance, and use of foraging sites with overhead cover, increased with increasing body size of YOY brook trout. We suggest that stream-resident salmonids become more wary with increasing size because the relative benefits of growing quickly, and hence taking risks while foraging, decrease with increasing body size.