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Abstract

The explicit assumption in the proposed use of ecological and biodiversity
indicators is that patterns of diversity and distribution observed in the indicator
taxon are reflected in other taxa, yet this assumption has rarely been tested. The use
of biodiversity and ecological indicators requires that their representativeness of
other taxa be demonstrated. This thesis examines the potential for using carabid
beetles as biodiversity and ecological indicators for other Coleoptera in Tasmania.
Species-occurrence data for carabids and a range of Coleoptera collected by
continuous year-long pitfall trapping at fifty-one sites in three biomes, dry
sclerophyll forest, remnant native grasslands and coastal sand dunes were used to
investigate the utility of carabid beetles as biodiversity indicators for overall
coleopteran diversity and for other selected beetle taxa.
Correlated species counts, correlations in rank ordering based on species richness,
and coincidence of hotspots revealed that while the patterns of diversity exhibited by
carabids did not necessarily predict the patterns of diversity of other individual
beetle taxa considered separately, they did, with a reasonable degree of accuracy,
indicate overall patterns of diversity for Coleoptera in all the biomes studied.
Carabid species richness was a good predictor of overall beetle species richness
within biomes and within vegetation community types.
Application of three reserve selection approaches: (1) Hotspots, (2) Representative
Species Richness and (3) Complementarity, demonstrated that a set of
representative areas, based on carabids species richness, gave proportional
representation for all Coleoptera. Representation for, all carabids using the
complementarity approach also gave protection to over 90% of all coleopteran
species. It is therefore likely that a set of representative areas in which carabids are
completely represented will substantially represent the diversity of other Coleoptera.
To assess the utility of carabids as ecological indicators for other Coleoptera, the
response of carabids and other Coleoptera to silvicultural practices (clearfelling and
slash burning) were examined and compared.
Morisita-Horn community similarity indices demonstrate that carabid and overall
Coleoptera species composition showed less variation within grouped age classes
than between different age classes in both forests. Results for other beetle taxa considered separately were more complex and varied with forest. In both forests,
UPGMA cluster analysis generally grouped the total beetle fauna according to
regrowth age, but indicated that the species composition of regrowth sites were
often similar to some old-growth sites. This pattern was observed for carabids in
the dry sclerophyll forest, but not in the wet. Other beetle taxa demonstrated more
complex patterns of clustering, with no clear evidence of site separation on age
class.
The family Carabidae did not reflect the exact response of other beetle families
considered separately. However, they did reflect the overall patterns of diversity
and distribution exhibited by beetles as a group in response to forest management
practices. Results demonstrated that monitoring particular carabid species would
provide evidence of the success or otherwise of management practices for other oldgrowth
dependent beetles.
The results reported in this thesis support the hypotheses that:
(i) the family of ground beetles (Carabidae) is an appropriate biodiversity indicator
for identifying and predicting the biodiversity patterns of ground dwelling
Coleoptera in most instances in Tasmania, and
(ii) that carabids are useful ecological indicators to predict and monitor the effects of
forest management on a wider range of ground-dwelling beetles in Tasmania.

Item Type:	Thesis - PhD
Authors/Creators:	Michaels, KF
Keywords:	Carabidae
Copyright Holders:	The Author
Copyright Information:	Copyright 1999 the Author - The University is continuing to endeavour to trace the copyright owner(s) and in the meantime this item has been reproduced here in good faith. We would be pleased to hear from the copyright owner(s).
Additional Information:	Thesis (Ph.D.)--University of Tasmania, 1999. Includes bibliographical references
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