Effective field-based methods to quantify personality in brushtail possums (Trichosurus vulpecula)

Abstract

Context There is growing recognition of the importance of animal personality in wildlife ecology and management. Individuals that differ consistently in their behaviours from others of the same population are considered to exhibit different personalities. Personality can be easily quantified with repeat tests on animals held in captivity. However, captive-based tests may not always be possible for logistical reasons and tests conducted in captivity can alter naturally occurring behaviours. Development of methods to assess personality in the field over short-term capture is an important alternative to long-term captive tests. Aims To develop and refine field-based tests that can be used to easily define personality traits of wild common brushtail possum (Trichosurus vulpecula), eliminating the need to bring individuals into captivity for an extended period of time. Methods We developed a series of short-term capture protocols to quantify personality traits of the common brushtail possum in the field, using handling-bag tests, modified open-field tests, trap-behaviour tests and release tests. Key results Personality traits of brushtail possums could be measured in several different ways, but refining methods was crucial to reveal traits efficiently. Behaviours related to several personality traits (boldness, docility and activity/exploration) could be measured rapidly in the field with our methods, and were repeatable over time. Conclusions Rapid, reliable and easy-to-perform quantification of personality of brushtail possums in the field is possible. This may sometimes be the only available option, and has advantages over long captive trials in terms of animal welfare and cost. Implications The present study provides a baseline for future research on the personality of common brushtail possums and its application to management and control strategies for the species.

Individuals in space: personality-dependent space use, movement and microhabitat use facilitate individual spatial niche specialization

“…Contrary to findings of some other studies (e.g., Herde and Eccard 2013 in common voles; Bajer et al 2015 in European green lizards) exploration and boldness did not correlate at the phenotypic level in bank voles. We tested individuals directly in the field after capture, which is a rare approach (see also Martin and Réale 2008 ; Dammhahn 2012 ; Best et al 2015 ; Mella et al 2016 ), and allowed the individual to enter the test apparatus voluntarily, which might facilitate disentangling of boldness-related and exploration-related behaviors (Carter et al 2013 ; Perals et al 2017 ).…”

Animal personality drives individual dietary specialisation across multiple dimensions in a mammalian herbivore

“…reproductive state, hunger) background environments. Our behavioural traits are standard traits used for quantifying personality of common brushtail possums (Mella et al., 2016) and are commonly used in ecological studies of other species (Carter et al., 2013). Our behavioural traits are also ecologically significant in affecting space use and problem‐solving in our study species (Wat et al., 2019, 2020).…”

“…We conducted personality tests following established protocols for measuring personality traits of possums in the field (Mella et al, 2016). We used an arena test, a widely used test for measuring a variety of personality traits (Carter et al, 2013) (Carter et al, 2013).…”

“…Following Mella et al (2016), we quantified the exploration trait as the time an animal spent out of its preferred compartment (defined as the compartment in which a possum spent most of its time). The mobility trait was quantified as time spent walking or standing on hind legs (hence a subset of activity), and the vigilance trait as time spent alert and looking out of the arena gazing directly with ears in upright position, indicating intense listening (Mella et al, 2016). The inclination to eat in an unfamiliar environment has been used to quantify boldness in previous studies (Dammhahn & Almeling, 2012;Wilson et al, 1994).…”

“…When quantifying personality traits, we pooled data from a longterm study conducted between 2014 and 2017. The pooled data were from four different studies/locations within the Greater Sydney area: (Mella et al, 2016) and are commonly used in ecological studies of other species (Carter et al, 2013). Our behavioural traits are also ecologically significant in affecting space use and problemsolving in our study species (Wat et al, 2019(Wat et al, , 2020.…”