Monitoring trap-related injury status during large-scale wildlife management programmes: an adaptive management approach

Abstract

Wildlife management and research programmes often rely on the capturing of live animals. All capture methods for wildlife involve a risk of injury. For that reason, monitoring of injuries should be completed concurrently, and efficiently, throughout the intervention programme, or study period, to uphold welfare standards. Here, we present a practical adaptive management system to monitor trap-related injuries as a component of broader attempts to maintain welfare standards. The monitoring system described is part of a large-scale tuberculosis-control management programme of European badgers (Meles meles) in the Republic of Ireland. Badgers were captured in stopped cable restraints. A standardised operating procedure was developed to allow for the necropsy of large numbers of badgers (N = 18,596) by a veterinary pathologist. As part of this programme, badger injury status was evaluated using a categorical severity scale ranging from 0 (no impact due to capture) to 6 (death) for badgers captured in restraints. No restraint-related deaths were recorded over the study period. Eighty-four percent of captured badgers exhibited no impact or only superficial hair/skin compression (scale 0–1). Logistic models indicated that injury severity was significantly influenced by year, season, age class, gender, weight and the body position where the badger was captured. Despite the low prevalence of severe injuries recorded, the proportion of animals with a minor injury type (skin oedema; scale 2) increased during the study period. This highlights the need for continual sensitive welfare vigilance during prolonged programmes. We suggest improvements to the current programme and additional adjustments for future vaccination campaigns. We contend that this type of monitoring, coupled with adaptive management strategies, is essential for wildlife programmes to maintain high animal welfare standards, at least in terms of injuries, but also highlight that trap injuries are only one component of animal welfare. We suggest that this adaptive management system could serve as a template for other similar wildlife programmes.