Stephen Clark recently spoke of his experience of
waterbirds at Lake Linlithgow, 15 km east of Hamilton in SW
Victoria (Australia). The lake is a permanent freshwater
wetland of 944 hectares formed in shallow depressions of
the Western Districts basalt plains.
The Wetlands Database has 39 waterbird counts for this site
with the oldest from Jan 1971 and the most recent from
February this year (Summer Waterfowl Count). Over 43
waterbird species have been recorded for this wetland with
those identified by Stephen included in this list.
Interestingly the absence of Great Crested Grebes,
Blue-billed Ducks and Black Fronted Plovers noticed by
Stephen is also evident in the Database information for
September. Likewise with Black Swans, over 4000 birds
have been recorded at any one time, especially over the
summer months, but sometimes there are none.
Many Australian wetlands have annual cycles of changes in
depth, salinity and turbidity but I am unaware if any
monitoring work is being done on this lake to record such
changes. It would be worthwhile to know what these
fluctuations in bird numbers are due to. Changes in
salinity may be a contributing factor, but no doubt
adjacent land use, recreation activities (boating, fishing,
hunting) as well as landuse in the catchment all have an
impact on this large wetland. The rseponse of waterbirds
to climate and seasons must also be recognised.
I encourage all birdos to keep complete records of
waterbird counts at any sites they visit (and fwd them to
the relevant state database) so we can better understand
what may be happening to these important habitats.
Birds may be useful bio-indicators for changes in the
health of our environment.
Cheers Martin
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Martin O'Brien
Scientific Officer - Flora and Fauna Guarantee
Flora and Fauna Program
Department of Natural Resources and Environment
4/250 Victoria Pde.,
East Melbourne 3002
Victoria AUSTRALIA
tel: + 61 3 9412 4567
fax: + 61 3 9412 4586
e-mail:
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