Helminth communities in small mammals in southeastern new south wales

Abstract

1. 1. Changes in the composition and abundance of 5 marsupial and 3 eutherian mammal species, and of their helminth communities pre- and post-perturbation by wildfire at Nadgee and Timbillica State Forests in southeastern coastal New South Wales during the period September 1977 to September 1985 are reported. 2. 2.Dasyurid marsupials ( Antechinus stuartii, Antechinus swainsonii and Sminthopsis leucopus), peramelid marsupials ( Perameles nasuta and Isoodon obesulus) and native eutherian rodents ( Rattus fuscipes and Rattus lutreolus) occurred pre-fire. These species and the introduced house mouse ( Mus musculus) occurred post-fire. 3. 3. All host taxa harboured a diverse helminth fauna dominated by nematodes. The helminth communities in A. stuartii, A. swainsonii, S. leucopus and R. lutreolus represented more than 70%, those in P. nasuta, R. fuscipes and M. musculus represented more than 50% and that in I. obesulus represented less than 40% of the total helminth faunas known to occur in these hosts throughout their geographic ranges in Australia. 4. 4. Adult nematodes of Capillaria sp. 11 and Tetrabothriostrongylus mackerrasae occurred in all host groups, those of Peramelistrongylus skedastos occurred in both marsupial groups but not in rodents, larval stages of the ascaridoid nematode Ophidascaris robertsi occurred in all host groups and physalopterid nematode larvae believed to be Abbreviata spp. occurred in dasyurid marsupials and in rodents but not in peramelid marsupials. 5. 5. Four helminth communities were recognised: one in the dasyurid marsupials, a second in the peramelid marsupials, a third in the native rodents and a fourth in the introduced house mouse. 6. 6. Differences in the helminth communities in host taxa pre- and post-wildfire were associated with the ecological strategies of the hosts and their roles as opportunistic invaders ( M. musculus), fire-enhanced species ( S. leucopus) or slow recolonisers ( P. nasuta) post-perturbation by wildfire.