It's a trap: is sampling bias due to animal personality always inevitable? (#309)
Within a population, individuals can often exhibit consistent differences in a range of behaviours across time and context (behavioural type) that are also correlated (behavioural syndrome). Recently, it has been suggested that an individual’s behavioural type can influence its probability of detection and capture during sampling. As a result, certain trapping methods may be inherently biased towards targeting a non-random sample of the population with wide ranging implications – from the way we conduct ecological research to the management and conservation of species. But is sampling bias always inevitable? Currently, studies have focussed almost exclusively on the efficacy of passive trapping methods (e.g. baited traps) that rely on the arrival and inspection of animals, where bold, explorative individuals are typically oversampled. Whether more active search strategies result in similar bias remains unclear. In this study, we compared three different trapping methods (hand capture, pitfall trapping and mealworm fishing) in their ability to capture a range of behavioural types within a population of the delicate skink (Lampropholis delicata). We also tested whether a behavioural syndrome was present. Whilst significant behavioural variation existed within the population, we found no difference between individuals caught in the three trapping methods amongst five behavioural traits. However, we did find the presence of a behavioural syndrome, where skinks that were consistently more active, explored an environment faster and were more likely to bask with other skinks. We suggest that trapping bias is not ubiquitous, but instead might only be associated with passive trapping methods that involve the response of animals to novelty.