Genetic monitoring of southern hairy-nosed wombats over two decades reveals that individuals can live for at least 18 years in the same warrens

Abstract

Survival and growth rates are important demographic parameters to understand for long-term management of populations. Eighteen years have elapsed since non-invasive genetic methods were used to identify southern hairy-nosed wombats (Lasiorhinus latifrons), and determine space use and relatedness at Brookfield Conservation Park, South Australia. Because the species is long-lived (>30 years) and genetic methods can identify all or most wombats that use an area, it is possible to determine whether population size or warren use have changed and if any individuals are still alive. To this end, in April 2017 we collected hair from wombats from the same warrens as the earlier study using sticky tape suspended across burrows. We subjected DNA from selected hairs to 10 microsatellite loci and a Y-linked sex marker, and identified 76 wombats. Five wombats were detected 16-18 years before, and four of them were found in warrens that they had used previously. The number of tapes hit, wombats detected, and warrens used were greater than in April 2001 and similar to September 2001. This study illustrates that non-invasive sampling methods can be used to track free-ranging individuals in continuous habitat across decades, despite rapidly evolving genetic technology that can strand older datasets.