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The Magpie Goose has, these days, become a wildlife
symbol of Australia's top-end and very few people consider it to be a
southern species any longer. Indeed most wildlife books will show
the distribution of this species as entirely northern.
Nevertheless the map above shows that it is widespread in Victoria where
permanent and seasonal wetlands are found. The species has not
made this recovery on its own but rather from an active breeding and
release program started in the 1960s by the Victorian Government.
The source of the breeding stock is animals captured from northern
Australian populations and it has been very successful.
Consequently, in 1984, government breeding programs for the species
ceased.
In 1997 Magpie Goose was listed as a threatened species in Victoria
under the now defunct classification of
insufficiently known,
indicating that not enough information had been gathered on the state
populations to make a clearer determination of conservation status.
By 2002 the species was classified as
endangered in Victoria, in 2005 this
was downgraded to vulnerable
and now it is considered to be
near threatened, that is, almost secure.
The conservation program for Magpie Goose in
Victoria appears to have been successful but there are two matters which
need to be considered before accepting such a conclusion. The
first is that there is doubt cast by some biologists that the species
has been successfully established as a self-sustaining breeding
population in Victoria. The only known natural breeding population
is in Tower Hill, western Victoria, and although the species range seems
to be expanding (records for Magpie Goose, and new locations, have
increased steadily over the past decade) it is argued that there
is no solid data to back up the assertion that this is due to breeding
within the state.
The second matter is one of provenance. Biologists are usually
quick to point out that any restoration programs for natural ecosystems
involving the re-introduction of native species, must always seek to use
local breeding stock. That can't be claimed for the Magpie Goose
in Victoria. What we have is an apparently expanding population of
a bird species that has been recruited from several thousand kilometres
to the north. Clearly these animals have found their way to places
that Magpie Geese inhabited at the time of European settlement, and the
expansion has the appearance of a natural process, but it is a moot
point whether Victoria is now home to native Magpie Geese or whether the
species is extinct in this state and its ecological niche has been
filled by an introduced form.
© Paul Gullan, Viridans Biological Databases
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