A study of the behavioural ecology of the woylie (Bettongia
penicillata) was conducted between November 1986 and September 1987
on a population that had been introduced to Island A, Venus Bay in
South Australia. The primary aim of the research was to establish
the reasons for the success of this population of approximately 20
individuals which survives in an environment which is considerably
different from the pockets of forest and woodland habitats comprising
the present range of this species in Western Australia. This
knowledge will assist wildlife authorities to identify suitable
reintroduction sites within the former mainland range of B.
penicillata.
Scat analysis revealed that woylies on Island A consumed a
catholic diet of dicotyledon leaf material, seasonal fruits and
berries, and invertebrates. Endomycorrhizal fungal spores were
common in scats during spring and are possibly derived from the gut
of Scarab beetle larvae that were present in the scats at this time.
Fungi are an insignificant dietary component of woylies at Venus Bay.
The home ranges of woylies on Island A overlapped considerably
and were significantly smaller than the "feeding" areas recorded for
Western Australian conspecifics. Separate "feeding" and "nest" areas
could not be identified on Island A as refuges were dispersed
throughout the home range and were at a density of approximately
three times that reported for Western Australian woylies. The refuge
sites used by woylies on Island A were relatively simple
constructions and contrasted with the more complex double-layered
structures described for mainland woylies. Refuge sites on Island A
were generally located beneath dense bushes. They provided little
protection from prevailing temperature and relative humidity but did
provide cover and ameliorate the effects of insolation. Refuges were
exclusive to individuals. Males maintained a greater degree of
spatial separation from one another during refuge occupation than
they did from females, or females from each other.
No significant difference between male and female body masses
was detected, while the mean body mass recorded in December was
significantly higher than at other times. The woylies at Venus Bay
had significantly lower masses than those reported for a population
of woylies at Tuttanning in Western Australia. The limited genetic
base of the founding population and competition for food among this
high density population are the most likely reasons for the lower
masses of woylies on Island A.
This study demonstrates that woylies can be successfully
introduced into a wild, modified environment if their basic habitat
requirements of suitable cover and diet are met. A broad diet, the
abundance of suitable food species and adequate refuge sites within a
small area, together with the absence of predators and fire, have all
contributed to the success of the woylie population introduced to
Island A. Active management is required to monitor and manipulate
such small populations to ensure that genetic viability is maintained
and the long term survival of the species is secured.
Management: Recommendations
1. Monitor the population dynamics and genetic profiles of wild
woylie populations in Western Australia.
2. Monitor the genetic profiles of woylies on Island A and other
introduced populations.
3. Identify and acquire habitats similar to, and within, those
of B. penicillata's former range, remove stock and exotic
herbivores, implement and maintain predator control measures,
and foster the growth of food species suitable for woylies.
4. Conduct research at proposed introduction sites to
establish the fire regimes that would maintain adequate food
and cover for woylies.
5. Introduce fresh genetic stock from wild Western Australian
populations into the existing small populations in South
Australia and simultaneously cull adults from the receiving
population.
6. Maintain management practices to protect relic populations
in Western Australia and newly established populations at
introduction sites.
| Identifer | oai:union.ndltd.org:ADTP/219158 |
| Date | January 1989 |
| Creators | Nelson, Lyn, n/a |
| Publisher | University of Canberra. Applied Science |
| Source Sets | Australiasian Digital Theses Program |
| Language | English |
| Detected Language | English |
| Rights | ), Copyright Lyn Nelson |
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