Alert and flight initiation distances of Chilean Flamingo and American Oystercatcher to anthropogenic stimuli in a stopover site

Abstract

ABSTRACT Tourism provides benefits, such as economic incentives, increasing support for conservation. However, it can also evoke responses in wildlife and be analogous to predation risk. As tourism increases, adequate planning and management is necessary. Chilean Flamingos (Phoenicopterus chilensis) and American Oystercatchers (Haematopus palliatus) were exposed to four stimuli (single walker, group of walkers, car, and kayak) in a stopover site to determine their response and estimate minimal approach distances, controlling the effect of potentially influential factors. Flight initiation distance and the distance at which birds change its posture or orientation to monitor an approaching threat (alert distance) were identified as response distances. Kayaks and cars allowed closer approaches than single walkers and groups of walkers for both species. The Chilean Flamingo exhibited responses to approaching stimuli at longer distances compared with oystercatchers. Potential factors (starting distance, month, season, initial behavior, and wind speed) including large variations among individuals, and influenced bird responses. To reduce the effects of tourists on bird behavior in an important stopover site, the minimal approach distance can be set at 80 m for the American Oystercatcher on the beach and 240 m for the Chilean Flamingo when walking and 207 m when kayaking in the estuary.