Low levels of faecal cortisol in bank voles (Myodes glareolus) in response to live-trapping

Small mammal trapping is a commonly taught field technique in ecology and population biology. However, there are still open questions regarding the extent to which trapping affects the welfare of small animals. This study investigated faecal cortisol as a non-invasive measurement of the physiological stress response of bank voles (Myodes glareolus) to live-trapping. Faecal cortisol concentrations were similar between samples collected from trapped and non-trapped voles, but were negatively correlated with capture duration. This result may suggest that any physiological stress response was short-lasting and the animals habituated to the trap. As such, effects on faecal cortisol were not apparent as mean faecal cortisol concentration was determined from multiple collected faeces. Future work should focus on characterising the potential stress response to trapping with greater temporal resolution.