Digging for answers: defining the external architecture of the southern hairy-nosed wombats’ (Lasiorhinus latifrons) subterranean excavations

Abstract

The southern hairy-nosed wombat (Lasiorhinus latifrons) is a large, nocturnal, herbivorous, burrowing marsupial, endemic to the semi-arid and arid regions of southern Australia. The active burrow of L. latifrons is used as the primary feature in population estimations. Therefore, accurate identification of an active burrow is vital, especially when other burrow-like structures exist. Entrance attributes such as width, height, the length and angle of the path leading to the entrance, and signs of wombat activity are indistinguishable between the different structures, making differentiation between them impossible without inspecting the structure beyond the entrance. Structures leading from entrances were identified in the field as possible burrows, blinds, and go-throughs. An unmanned aerial vehicle provided accurate images from immediately above 12 active wombat warren systems in the mid-north of South Australia, to support ground-truthing for mapping and verification of these structures. Active possible burrows (APB) were found to occur in proportionally lower numbers than the active non-burrow structures (ANBS) of blinds and go-throughs, varying in proportion from as high as 1:2 to as low as 1:11 (APB:ANBS). Defining an active burrow and other tunnels leading from an entrance increases accuracy in burrow identification used in population estimations, while recognising the existence of additional architectural features is vital to understanding the functional potential of L. latifrons as an ecosystem engineer.