As I have recently researched the conservation status of a
number of crakes, rails and bitterns in Victoria
(Australia) I thought the following of interest to
subscribers.
With respect to Lewins Rail and Baillon's Crake I have
critically examined the state fauna databases, literature
and canvassed bird observers and clubs for their records.
These particular species were reported more frequently in
the RAOU (now Birds Australia) Atlas years of 1977-81
than they have been since. Even the last major
drought of 1982-83 didn't appear to have increased the
numbers of cryptic waterbirds reported to databases.
Interestingly Australasian Bitterns have been recently
recorded in various literature in southern Victoria, but
the sightings are invariably of single birds and, on
average, I suspect the numbers of these birds reported
hasn't changed much in recent years.
The conclusion I have come to on examination of the data is
that several cryptic waterbirds, bitterns and also egret
species have declined in the state mainly due to
loss of feeding and breeding habitat in combination
with alteration of natural hydrological regimes.
Recent apparent increases in observations of these
waterbirds may not be more than normal for each
species.
I am interested in what other states believe may be
happening in this regard.
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Martin O'Brien
Scientific Officer - Flora and Fauna Guarantee
Flora and Fauna Statewide 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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