Behavioural mechanisms of detection bias in applied ecology and wildlife management

Abstract

Detecting animals during wildlife surveys underpins the validity of outcomes for pest control, conservation and research. Most surveys rely on animals deciding to engage with a device, hoping the reward outweighs any perceived danger. Animal personality, however, can shape risk-reward decisions by individuals, potentially driving heterogeneity in detection probability and undermining sampling reliability. In this thesis, I investigated personality as a mechanistic driver of detection bias and examined interactions between personality and the risk-reward properties of different survey methods. First, I tested whether high recapture rates equate to low bias. I surveyed the mountain pygmy-possum (Burramys parvus, recapture rate: 0.78-0.92) and found that animals that took greater risks had greater recapture probabilities. I suggest that irrespective of survey assumptions, heterogeneity in response to the perceived risks of a device can drive a bias. Next, I investigated whether a personality bias can differ between methods. I surveyed the military dragon (Ctenophorus isolepis) using noosing and pitfall traps and found that the methods sampled distinctly different personality spectrums. I then examined the interaction between personality and device properties. I surveyed the black rat (Rattus rattus) and exposed populations to novel devices with risk-reward manipulations and found that a personality bias increased with the perceived. Finally, I investigated the transgenerational transfer of personality. I created breeding population of house mice (Mus musculus) with biased personality expressions in founders. However, I found no evidence that offspring reflected founder personality. My findings advance our understanding of how animal behaviour and specifically, personality, acts as a mechanistic driver of detection bias. Strategies to overcome a personality bias should target a board personality spectrum by accounting for the different risk-based decisions animals make.