Greg Oakley inquires about the status of the Brolga (Grus rubicunda) in
Victoria. The species is listed as a threatenend taxon under the Flora and
Fauna Guarantee Act and an Action Statement (management plan) has recently
been completed that addresses its conservation in Victoria.
The most recent population survey of the species in Victoria (1992)
indicates there to be about 600 birds and the southern populations are now
thought to be isolated from those in northern Australia. The main threats
to the birds' conservation are:
Activities that threaten the Brolga's preferred breeding habitat include:
- Drainage and modification of wetlands.
- Alteration of flood regimes during the breeding season which can cause
nest abandonment.
- Modification of vegetation structure and species composition, water
quality or soil structure at breeding and feeding sites.
- Widespread use of herbicides and pesticides especially in close proximity
to breeding sites.
- Disturbance by hunting activities where young birds are still in the
breeding wetland.
- Introduced predators taking eggs and killing chicks.
- Wildfire and burning programs, which remove nest material.
- Grazing by stock.
- Subdivision and fencing of large private landholdings.
- Erection of structures such as overhead powerlines.
- Use of wetlands for irrigation and/or re-use systems.
Flocking sites are threatened by:
- Disturbance by hunters during the duck season and deposition of lead shot
in wetlands.
- Loss of habitat due to changes in vegetation, for example, changes in
agricultural practices.
- Catchment degradation resulting in changes in water quality, including
increased salinity, siltation or flooding.
- Poisoning of agricultural pests eg. crickets.
- Erection of structures such as overhead powerlines.
No doubt the historical populations around Kerang are all but gone, as
indicated by Greg. Unfortunately the outlook for Brolga conservation i
southern Australia isn't good if the threatening processes acting on it are
not addressed.
The Action Statement will be released onto the Department of Sustainability
and Environment web site before the end of the year. I am happy to post
hard copies to those interested though. Please provide a name and full
mailing address should you like one.
I encourage all birdos to forward their (Victorian) sightings of any
threatened birds to the Atlas of Victorian Wildlife (Melbourne 9450 8600)
so we can keep tabs on their populations, movements and breeding.
Historical accounts of species are also invaluable information, especially
if the observations can be pinned down to a specific locality and
month/year.
cheers, Martin
Martin O'Brien
Executive Scientific Officer, Scientific Advisory Committee
Department of Sustainability and Environment
4/250 Victoria Pde., East Melbourne 3002
Tel: 9412 4567 Fax: 9412 4586
(prefixes: Interstate 03 International 613)
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