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Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

Diet and feeding selectivity of common wombats

Murray C. Evans A B C , Cate Macgregor A and Peter J. Jarman A
+ Author Affiliations
- Author Affiliations

A Ecosystem Management, University of New England, Armidale, NSW 2351, Australia.

B Present address: Environment ACT, PO Box 144, Lyneham, ACT 2602, Australia.

C Corresponding author. Email: murray.evans@act.gov.au

Wildlife Research 33(4) 321-330 https://doi.org/10.1071/WR05047
Submitted: 6 May 2005  Accepted: 21 April 2006   Published: 27 June 2006

Abstract

The seasonal diets and feeding selectivity of common wombats (Vombatus ursinus) in mountainous eucalypt forest, eucalypt woodland and pasture were determined using faecal analysis. Grass species contributed the largest proportion (95%) of epidermal fragment area in faecal pellets, with at least 20 species being eaten. The most abundant grasses in pellets in all seasons were the tough, wiry snow grasses (Poa sieberiana and P. labillardieri), with Microlaena stipoides comprising a substantial proportion of the diet in summer and autumn. Grass leaf was the most abundant plant part in pellets (81%), with grass stem and grass sheath comprising 11%. The seasonal proportion of grass seedhead in pellets varied from just traces during autumn and winter to a substantial component of the diet during summer (21% of epidermal fragments in pellets). Forbs comprised less than 1% of pellet material, and tree or shrub species were not detected in the diet. Feeding selectivity (and hence dietary niche breadth) varied seasonally; wombats become less selective in their feeding as plant diversity and abundance decreased. Positive selection was shown for monocots and negative selection for forbs. Grass species were eaten in broadly similar proportions to their abundances in the field, but with moderate to strong selection or rejection of a few species.


Acknowledgments

Funding for this project came from an Australian Research Council Grant to P. J. Jarman, C. N. Johnson and B. Green and a Commonwealth Postgraduate Scholarship to M. C. Evans. We thank two anonymous reviewers for comments on the manuscript.


References

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Appendix 1.  Vanderploeg and Scavia E* index of food utilisation in relation to food availability for plant species in three vegetation types (pasture, forest, woodland) over two years from summer through to spring
Values near +1 indicate high selection for a food class, values near –1 indicate high selection against a food class. Means (bold) are given with their standard error. n = 10 for each season
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