Review of the management of feral animals and their impact on ...

habitats would most likely result in strong declines <strong>and</strong> potentially localised
extinctions.
3.8 New pests
New pests can be expected to invade <strong>the</strong> Rangel<strong>and</strong>s in future (Table 10). Of <strong>the</strong>
vertebrates, fish <strong>and</strong> birds are among <strong>the</strong> groups most likely to invade, as a
consequence <strong>of</strong> pet escapes <strong>and</strong> releases. Lintermans (2004) has documented <strong>the</strong>
increasing number <strong>of</strong> aquarium fish forming wild populations in Australia. The worst
affected catchment is <strong>the</strong> Ross River at Townsville, where cichlids are thought to be
washing into <strong>the</strong> river from outdoor ponds after torrential rains (Low 1999). Tropical
catchments next to large urban centres are most at risk, because most aquarium fish
are tropical. Even very remote catchments are at risk. Peter Kendrick (pers. comm.)
reported recently seeing a new fish, black with reddish fins (probably a cichlid),
populating a waterhole in <strong>the</strong> remote Kennedy Range National Park in Western
Australia, at a popular swimming spot.
The example <strong>of</strong> barbary doves <strong>and</strong> spotted turtle-doves recently forming <strong>feral</strong>
populations in Alice Springs shows that aviary releases or escapes can readily lead to
new <strong>feral</strong> populations. It is a matter <strong>of</strong> grave concern that during <strong>the</strong> first half <strong>of</strong> 2005
<strong>the</strong> Department <strong>of</strong> <strong>the</strong> Environment <strong>and</strong> Heritage received two applications to amend
<strong>the</strong> live import list, maintained under <strong>the</strong> EPBC Act, to include <strong>the</strong> collared dove as a
household pet. The collared dove has formed <strong>feral</strong> populations in many regions <strong>of</strong>
Asia <strong>and</strong> North America. It is a domesticated form <strong>of</strong> <strong>the</strong> barbary dove which has
exp<strong>and</strong>ed its range dramatically in Europe.
Aviary releases also have <strong>the</strong> potential to spread diseases to wild birds. The more
virulent forms <strong>of</strong> Newcastle Disease have <strong>the</strong> potential to cause mass deaths among
wild bird populations.
Game birds are also a serious concern. As noted in section 8.3.3, <strong>the</strong> newly-created
Game Council <strong>of</strong> New South Wales has a m<strong>and</strong>ate to manage Californian quail,
pheasant, chukhar partridge, peafowl <strong>and</strong> turkey for hunting. All <strong>of</strong> <strong>the</strong>se birds can
fly, so <strong>the</strong>y cannot not be constrained by fencing, <strong>and</strong> all <strong>of</strong> <strong>the</strong>m have formed <strong>feral</strong>
populations elsewhere <strong>of</strong> <strong>the</strong> world. A <strong>feral</strong> population <strong>of</strong> chukar patridge has recently
been reported from Gulgong, east <strong>of</strong> Dubbo, in New South Wales, <strong>the</strong> birds having
been released for a sporting shoot (Morcombe 2000).
As well, <strong>the</strong> Rural Industries Research <strong>and</strong> Development Corporation is promoting <strong>the</strong>
breeding <strong>and</strong> export <strong>of</strong> game birds, including quail, guineafowl, pheasants, <strong>and</strong>
partridges, throughout <strong>the</strong>ir report, Identification & Development <strong>of</strong> Opportunities for
Exporting Game Birds. Most game birds in Australia are now bred on a small scale
for <strong>the</strong> domestic market, but opportunities have been identified for a massive increase
in production to exploit <strong>the</strong> export market to Singapore <strong>and</strong> Hong Kong. Large
escapes from game farms could easily result in <strong>the</strong> establishment <strong>of</strong> <strong>feral</strong> populations.
Among mammals, <strong>the</strong> establishment <strong>of</strong> new deer species is a grave concern.
According to <strong>the</strong> bioclimatic modelling <strong>of</strong> Moriarty (2004), <strong>of</strong> <strong>the</strong> six deer presently
found as <strong>feral</strong> species in Australia, hog deer <strong>and</strong> sambar deer have <strong>the</strong> greatest
potential to form <strong>feral</strong> populations in <strong>the</strong> north <strong>of</strong> <strong>the</strong> country, yet nei<strong>the</strong>r species is
presently established <strong>the</strong>re. Hog deer <strong>and</strong> sambar have formed successful <strong>feral</strong> herds
in Victoria, in a climate that is colder than <strong>the</strong>ir natural habitat in South East Asia. If
<strong>the</strong>y escape from captivity in nor<strong>the</strong>rn Australia, as seems likely, <strong>the</strong>ir potential to
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