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A key factor influencing wildlife responses to human activity is the degree to which animals have been previously exposed to human stimuli. On subantarctic Macquarie Island, gentoo penguins Pygoscelis papua breed in areas of high and low human activity (on and off-station, respectively). We investigated the behaviour and breeding success of gentoo penguins on and offstation, by a) comparing the behavioural responses of guarding gentoos before, during and after exposure to standardised pedestrian approaches, and b) employing an observational study to determine how human activity may have contributed to within-season breeding success in light of other environmental and site variables.Behavioural responses to pedestrian visitation by gentoos off-station were significantly stronger than those of birds breeding on-station. However, no relationship was found between pedestrian activity and breeding success off-station. Breeding success was, however, positively related to colony size, and negatively related to the activity of other penguins, the number of nearby southern elephant seal Mirounga leonina harems and the location of colonies within short grassland. On-station, breeding success was amongst the highest recorded for that season. Habituation, predator exclusion and the relevance of these findings for management are discussed.

The post-release survival of rehabilitated oiled little penguins (Eudyptula minor) was monitored over 20 months following the Iron Baron oil spill (10 July 1995) in northern Tasmania, Australia. During rehabilitation, over 1800 little penguins were individually banded and detailed records kept of factors including their degree of oiling, sex, capture and release mass and capture and release condition. Post-release survival of rehabilitated oiled little penguins was assessed through regular trapping of birds over two breeding sites (Ninth Island and Low Head). The minimum estimate of post-release survival was 59% for penguins from Ninth Island and 44% for penguins from Low Head. Rehabilitated oiled little penguins had significantly lower survival than non-oiled birds at both sites. The main factor affecting post-release survival was the extent of oiling, which itself had a significant influence on the capture mass and condition of birds. Combined, these factors had the greatest power to predict post-release survival. Other factors that significantly affected post-release survival included release mass and condition, and the sex of the bird. The duration of rehabilitation and whether birds were translocated (200–410 km) from their capture site prior to release did not significantly affect survival. The results of this study indicate how aspects of oiling, the condition of birds and rehabilitation affect post-release survival. As such, they will help improve the success of wildlife rehabilitation in future spills, and highlight the importance of individually marking rehabilitated oiled wildlife and post-release monitoring in assessing the success of rehabilitation programs.

Increases in the number of people travelling to Antarctica has led to more frequent interactions between people and Antarctic wildlife, yet the effects of visitation on the animals has received limited scientific assessment. This study conducted experiments to measure the responses of incubating Adélie penguins (Pygoscelis adeliae) to controlled human approaches to determine which approach distances and approach styles caused the least disturbance to the birds. Three minimum approach distances were tested: 30, 15, and 5 m. Approaching penguins to 30 m had no measurable effect on either their behaviour or heart rate, while approaching as close as 15 m significantly elevated their heart rates above resting, undisturbed levels even though there was no behavioural indication of this response. Approaching penguins to 5 m significantly interrupted the penguins' incubation behaviour, with the potential to cause egg-cooling. Approaches to 5 m elevated heart rates above those measured when birds were undisturbed, approached to either 15 or 30 m, or exposed to ‘natural’ disturbances (that is, other penguins or south polar skuas, Catheracta maccormicki). The study also identified certain Adelie penguin behaviours that may be indicative of disturbance in response to human visitation. People visiting breeding penguins could learn to identify these behaviours, so they can monitor and modify any effects of their visit.