The population status of southern hairy-nosed wombats (Lasiorhinus latifrons). II. Landscape factors affecting distribution and abundance

Abstract

The southern hairy-nosed wombat has a fragmented distribution across the arid and semiarid regions of southern South Australia and south-eastern Western Australia. Its distribution and abundance are highly patchy, with large clusters of warrens in some areas but few to no warrens in adjacent areas. In order to understand why this occurs, we mapped the species’ distribution and correlated the locations of over 8130 data points (5349 presence points and 2781 absence points) with environmental and landscape data. Overall, the wombat distribution is influenced by rainfall, with no wombats in areas where the mean annual rainfall is <154 mm. Abundance is greatest in areas where rainfall is >227 mm per annum. At the regional/local scale, warrens are found only in areas where the soil clay content is between 9 and 40%, and warren abundance is higher in open vegetation classes (saltbush/bluebush shrublands, grasslands) than in closed vegetation (mallee woodlands with shrubby understorey). Over-riding all of these environmental influences are anthropogenic land-use practices: although 38% of the wombats are located in protected areas and 51% are located on grazing land, they are virtually absent from croplands (~2%).