Human activities at night negatively impact Little Penguin (Eudyptula minor) numbers and behaviours

Abstract

The presence of humans within the natural environment is increasing worldwide. Assessing the impact of such activities on wildlife is crucial for declining populations where human disturbance adds to existing pressures. Here, we investigated how human activities at night influenced Little Penguin Eudyptula minor numbers and behaviours (specifically return time, number of vocalizations and time spent in vigilance) on Granite Island, a declining population in South Australia, Australia. We combined data from regular night surveys with continuous video and audio monitoring to assess the impact of human activities on the Little Penguins. The use of white light (i.e. from torches or camera flashes) by people was the most frequent activity recorded at night (recorded on 65% of the monitored nights). Fewer penguins were found on land at night when Dogs Canis lupus familiaris were present, but not when the number of people increased, when concerts occurred, or when white lights were used. Little Penguins were observed more often returning late from sea at night when Dogs were present and when white lights were used, but not when concerts occurred. An increase in penguin vocalizations at night correlated with the presence of Dogs and the occurrence of concerts, whereas penguins vocalized less when white lights were used. The time Little Penguins spent in vigilance did not correlate with any of the disturbances analysed. Our study also highlights the impact of coronavirus disease 2019 (COVID‐19) on wildlife, as the occurrence of human activities increased significantly following the implementation of the COVID‐19 health protection measures. These results add to a growing body of literature suggesting that human activities on land, and their consequent disturbance(s), may affect the numbers and behaviours of wildlife and that appropriate measures need to be developed to limit such impacts.

COVID-related anthropause highlights the impact of marine traffic on breeding little penguins

“…A recent study identified the negative effect of anthropogenic activities, i.e. white light sources, at night on little penguins (Costello & Colombelli Négrel, 2023), but evidences are mixed since other study find the opposite (Rodríguez et al, 2018). Multiple hypotheses could explain the absence of response during the anthropause in our study.…”

Evaluating risks to seabirds on the urban–coastal interface: Modelling dog attacks on little penguin populations in Tasmania

“…Our study did not consider what impact just the presence of dogs (but not attacks) might have on little penguin behaviour and how this might influence colony size. For example, in South Australia, Costello and Colombelli‐Négrel (2023) found that fewer little penguins were observed on land at night when dogs were present and that penguins returned to land later at night more often, compared to when dogs were absent.…”

“…In recent decades, some little penguin colonies have decreased around Australia and New Zealand (Dann, 1991(Dann, , 1994Dann et al, 2000;Stevenson & Woehler, 2007;Wiebkin, 2011). Like many other seabirds, human activities can negatively impact little penguins (Costello & Colombelli-Négrel, 2023).…”