What a camera trap survey can reveal about the behaviour of an invasive species: Insights from coypus Myocastor coypus in an urban park of central Italy

Abstract

Assessing the behaviour of invasive alien species is fundamental for their management. Coypu occurrence outside the native range poses ecological and economic threats, and effective management strategies are crucial, particularly in urban areas where interactions with humans are the most frequent. In this work, we analysed the temporal patterns of activity and behavioural repertoire of an urban population of coypus in central Italy, by means of camera trapping and focal sampling. Activity rhythms and time budget were estimated throughout the year and compared across seasons, sexes, and age classes; overlaps in coypu activity patterns with co-occurring potential predators and competitors were also assessed. Differently from natural areas, coypus in our study site were primarily crepuscular and nocturnal, with a significant reduction in activity during bright moonlight periods to limit predation risk, showing a high overlap with red foxes (the main natural predator) but minimal overlap with humans and unleashed dogs. Coypus spent most of their time swimming and foraging. Adult males were territorial and were the only sex scent-marking on both land and woods. Adult females played a crucial role in protecting offspring, together with subadults, and defended dens with cubs from conspecific and other species. Playing was strictly a kit prerogative. In general, controlling coypu populations, as imposed by EU regulations, is challenging due to their adaptability and high reproductive rate. We suggest that trapping efforts should focus on night-time activities near water bodies during warmer months, when coypu are more active on the land and thus more likely to encounter land-based traps. Overall, this study provides valuable insights into the ecology and behaviour of coypu in urban environments, aiding in the development of effective management strategies to mitigate the species impacts on native biodiversity and environments.