Little Penguins (Eudyptula minor) and Human Disturbance
Penguins are a much-loved taxon, and are frequently the subject of both scientific research and tourist visitation. Many species of penguin do not show a behavioural response to human presence, so it is often assumed that the penguins are not negatively affected. However, in the absence of a visible behavioural response, physiological changes such as increases in heart rate may use up vital energy resources and lead to population-level consequences. The personality of individual penguins may also affect how they react to human disturbance.There are an increasing number of commercial operations taking advantage of the apparent indifference of Little Penguins (Eudyptula minor) to human presence, such as the Oamaru Blue Penguin Colony at Oamaru, New Zealand. My study aimed to quantify the effects of human disturbance on Little Penguins. I recorded the heart rate (HR) of Little Penguins at Oamaru using artificial eggs, to measure responses to typical researcher and visitor interactions with penguins. Researcher interactions were: human speech, band checking, and weighing, and a penguin call playback was used as a control. I calculated the amount of energy expended by a Little Penguin in response to an invasive researcher interaction, i.e. weighing. HR responses to researcher interactions were compared with corticosterone responses obtained from the same individual penguins. I used chick mass data to compare chick growth and fledging weights between a colony visited by tourists and a control colony. Little Penguins at Oamaru had stronger HR responses to being weighed than to hearing penguin calls or human speech. However, some individual penguins reacted as strongly or more strongly to having their band checked than to being weighed. There was some correlation between HR responses and corticosterone responses, suggesting that individual penguins respond consistently on a shy-bold personality continuum. The HR of incubating penguins averaged over four-hour periods did not differ significantly between a colony visited by tourists and a control colony. However, female penguins in the ‘medium disturbance’ zone of the visited colony had significantly higher resting heart rate (RHR) than their male counterparts. The amount of energy used by a Little Penguin in response to being weighed was found to be negligible. Chick fledging weights at the visited colony were significantly lower than those at the control colony, which may affect their first-year survival.A balance must be reached between humans having close contact with wildlife, for purposes of research and education, and leaving the wildlife to itself. At Oamaru, current management practices are successful in facilitating the penguin colony’s growth while also permitting thousands of visitors to view the penguins every year. Future research focusing on individual penguins and the responses of particular personality types to environmental changes, including human disturbances, will aid the ongoing success of this colony.
Advisor: van Heezik, Yolanda; Ellenberg, Ursula; Cockrem, John
Degree Name: Master of Science
Degree Discipline: Zoology
Publisher: University of Otago
Keywords: blue penguins; little penguins; human disturbance
Research Type: Thesis