Behavioral and hormonal responses of Magellanic penguins (Spheniscus magellanicus) to tourism and nest site visitation

One of the results of human disturbance at seabird colonies may be the provocation of the typical vertebrate adrenocortical response to stressors, but there have been few studies that demonstrate this. The present study demonstrates that simple human presence at the nest site, without effects of capture or handling, is physiologically stressful for breeding Magellanic penguins (Spheniscus magellanicus) that are not accustomed to seeing humans. It also demonstrates that birds that have been exposed to very high levels of human visitation via tourism do not respond to human presence as a stressor, whereas those exposed to moderate levels of disturbance do not show evidence of habituation over a period of a few years. These results suggest that tourist visits should be concentrated in a small part of breeding colonies, allowing birds nesting in the visitation area to habituate, leaving the remainder of the colony free of disturbance. (C) 1999 Elsevier Science Ltd. All rights reserved.