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Project summary:
The impact of silvicultural practices (clearfelling, slash burning and sowing) on carabid beetle communities in tall wet Eucalyptus obliqua forests in southern Tasmania [including two sites in Warra along Manuka Road] was examined in a chronosequence of regenerating coupes. Total species richness (n = 18) was modest compared to other temperate forests and was not systematically changed by forest management, although it was considerably lower in 20 year old regrowth than in younger regrowth or old-growth controls, possibly due to habitat simplification. The Shannon-Weiner Index was a minimum in intermediate aged regeneration. TWINSPAN analysis assisted recognition of beetle communities typical of broad stages in the forest succession, with a major dichotomy between most old-growth sites plus young sites and intermediate plus advanced regeneration sites.
Significant influence was found for the age of regeneration and litter depth, but not bare ground percentage or soil pH. Survival of carabids in the habitat mosaic created by commercial forestry activity is likely to depend on both reinvasion from edges and survival of individuals in the fire-protected refuges that exist within the coupes. Pioneer species were winged, small in size, and non-endemic whereas the opposite was true of the fauna in the older sites. Carabids in eucalypt forests have good potential as indicators but their seasonality in occurrence demands that sampling be extended over most of the year.
Methodology: Traplines of pitfalls were used to investigate carabid beetle communities in a chronosequence of regenerating coupes.
Non-metric multidimensional scaling was used to test for the significance of certain environmental variables: age of regeneration, litter depth, ground percentage and soil pH.
Datasets: None available.
Publications: Michaels, K. & Bornemissza, G. (1999). Impact of clearfell harvesting on lucanid beetles (Coleoptera: Lucanidae) in wet and dry sclerophyll forests in Tasmania. Journal of Insect Conservation 3: 85-95.
Michaels, K.F. & McQuillan, P.B. (1995). Impact of commercial forest management on geophilous Carabid beetles (Coleoptera; Carabidae) in tall, wet Eucalyptus obliqua forest in southern Tasmania. Australian Journal of Ecology 20: 316-323.
Michaels, K. (1999). Carabid beetles as biodiversity and ecological indicators. PhD thesis, University of Tasmania, Hobart.
Michaels, K.F. (1999). Carabid beetle (Coleoptera: Carabidae) communities in Tasmania: classification for nature conservation. In: Ponder, W. & Lunney, D. (Ed.), The Other 99%: The Conservation and Biodiversity of Invertebrates. Royal Zoological Society of NSW, Mosman, pp. 374-379.
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