Contrary to our original hypothesis, the long-tailed mouse, a habitat generalist, showed better condition in the less disturbed site compared with the more disturbed sites. The implication of this finding is that even relatively generalist and ‘resilient’ common native species can be negatively affected by anthropogenic habitat degradation, albeit not at a level that is obvious from population distribution data alone. While significant
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differences in swamp rat relative abundances between anthropogenically degraded and undisturbed sites have been reported (Stephens et al. 2012), we found no apparent differences in indicators of stress or condition in this cover-dependent species in this study. We present two possible explanations for this observation: 1) The majority of individuals trapped in the harvested treatments were utilising the unlogged portion of these areas, and potentially minimising the impacts of loss of cover in these areas; or 2) populations may have been experiencing elevated physiological stress in both the harvested and relatively undisturbed sites, potentially due to fragmentation of the unlogged forest by minor roads. The results of this study highlight the risks to ecologists and land managers alike, of drawing assumptions from ecological
(abundance) measurements in isolation. Our results therefore illustrate the important role of physiological studies in complementing broader population-based studies with ecological monitoring and assessment goals.
3.6Acknowledgements
We would like to thank Diane Stephens, Hugh Fitzgerald, Natalia Atkins, Justin Bloomfield, Christina Borzak, Katrina French, Aaron Holmes, Alison Miller, Lisa O’Bryan, Martin O’Bryan, Kerri Spicer, Paul Tilyard, Veronica Tyquin, Laura Wood and Sam Wood for their help with fieldwork. Thank you to Barrie Wells (University of Tasmania), David Obendorff, and Erin Flynn for their training in blood sampling and scoring. We thank Sam Wood (University of Tasmania) for preparing the landscape map and Forestry Tasmania for providing the aerial photos. We would like to thank the following bodies for their financial support: Holsworth Wildlife Research Endowment, M.A. Ingram Trust, Co-operative Research Centre for Forestry and Forestry Tasmania. All work was completed under the University of Tasmania Animal Ethics Approval permit A10504 and the Department of Primary Industries and Water, Parks and Wildlife permits FA 09075 and FA10047; and with permission from Forestry Tasmania to conduct mammal trapping in State Forest.
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