Short-term behavioural and physiological responses have been linked to increasesin energy expenditure among wildlife exposed to human activity (e.g. Knight andTemple 1986a, 1986b, Gabrielsen and Smith 1995). For example, elevated heart ratesin Adélie penguins approached by humans triggers increases in energy consumptionand the number of prey items that must be consumed to replace spent energy (Culik1994). For species such as these, that breed in extreme environments, energy budgetsare precise and relatively finite, and absences from the colony to forage and replenishspent energy will almost certainly result in egg or chick predation.Other short-term effects reported include disruption of social activities amongIndo-Pacific humpback dolphins in Hong Kong (Leung and Leung 2003) and changesto fish behaviour (Scholik and Yan 2002), with unknown implications for interactingspecies.