Revista mexicana de biodiversidad
versión On-line ISSN 2007-8706
versión impresa ISSN 1870-3453
During 2004, we followed 72 natural burrows to determine the effects of disturbance on breeding success of Cassin's auklets (Ptychoramphus aleuticus). We used distance from a human settlement or path in the analysis of disturbance. Birds whose burrows were closer to the path or the village had a higher rate of nest abandonment and lower breeding success compared to birds nesting further away from the path or the village. Also, older and more experienced individuals represented a larger proportion of the breeding population on less disturbed areas than on highly disturbed ones, probably as older individuals tend to arrive earlier at the breeding grounds, and failed breeders may change burrow sites to move away from disturbance. P. aleuticus are adversely affected by human activity at colonies even if birds are not handled and burrows are not opened, and this has implications for conservation, and planning of ecotourism. On the long term, this can have negative consequences for this species and others with similar characteristics.
Palabras llave : human disturbance; Ptychoramphus aleuticus; breeding success; occupancy; island conservation.