Selection, characteristics, and frequency of use of shelter sites by the Southern Brown Bandicoot Isoodon obesulus obesulus and the Southern Long-nosed Bandicoot Perameles nasuta in a post-fire landscape

Abstract

Dense ground cover and understory can be important as diurnal shelter for terrestrial mammals. Fire can lead to the short-term removal of much of this shelter. Here, we report on the shelter site selection of the Southern Brown Bandicoot Isoodon obesulus obesulus and Long-nosed Bandicoot Perameles nasuta eight months after a wildfire. We analysed the number of shelters, frequency of shelter use, nest size, and shelter site microhabitat. Southern Brown Bandicoots used significantly more shelters than Long-nosed Bandicoots. Both species preferred to use shelters with significantly lower levels of transmitted light than matched control areas. Within the burnt landscape, Southern Brown Bandicoots located their refuges under regrowth eucalypts, whereas Long-nosed Bandicoots showed no preference for any microhabitat. Southern Brown Bandicoots built nests significantly higher above ground than Long-nosed Bandicoots. Nests built in more dense and darker microhabitats were significantly taller than those built in more open habitats. Following fire, the Southern Brown Bandicoot required a more dense groundcover to conceal its taller nests and was able to take advantage of regenerating mallee eucalypts for shelter. Land managers need to be aware that hazard reduction burning in coastal woodland and heath will temporarily deprive Southern Brown Bandicoots of diurnal shelter sites and should, therefore, where practicable, retain patches of unburnt dense undergrowth to ensure a mosaic of different aged habitat and habitat structure.