Seasonal variation in behavioral and physiological response in Magellanic penguins

VILLANUEVA, M. C.; BERTELLOTTI, M.; WALKER, B.

Campos do Jordao, Brasil

Congreso; 25th International Ornithological Congress; 2010

Ecotourism activity has expanded greatly in Patagonia, Argentina, over the last two decades. While ecotourism is economically important, there is the potential for significant negative effects of tourist visitation to wildlife. We initially studied the effect of tourist visits on Magellanic penguins (Spheniscus magellanicus) in San Lorenzo colony, located in Peninsula Valdés, Chubut, Argentina by measuring both a behavior response (distance until initiation of the defensives “head turns”) as well as a physiological response (glucocorticoid stress-hormone response to capture and restraint) in both tourist-visited and non-visited female penguins during the incubation period. We found that while behavioral responses (distance at which started doing head turns) were less severe in tourist-visited penguins, the glucocorticoid stress response was the same. Thus, behavioral habituation to visitation was present, whereas there would not be physiological habituation to disturbance. To examine the potential seasonal effects on stress, we then measured behavioral and hormone response in non-disturbed female penguins in three additional periods (early chicks, late chicks and molt). Behavioral responses in undisturbed females did not vary throughout the season. However, we found that stress hormone levels differed, being highest during “early chick” and most reduced during molt. Thus, it appears that physiological responses of penguins are dependent on season, which may have particular pertinence for penguins being visited by tourists.