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

• Goats degrading temperate woodl<strong>and</strong>s
• Banteng at high densities degrading Garig Gunak Barlu National Park
• Donkeys in high densities degrading Indigenous l<strong>and</strong>s in <strong>the</strong> Nor<strong>the</strong>rn Territory
• Foxes, dingoes, pigs <strong>and</strong> cats preying on <strong>the</strong> eggs <strong>of</strong> two freshwater turtles in
Queensl<strong>and</strong>
• Pigs preying on turtle eggs in north Queensl<strong>and</strong>
• Dingoes <strong>and</strong> dogs preying on turtle eggs in <strong>the</strong> Nor<strong>the</strong>rn Territory.
7.1.1 Deer
Deer have suddenly emerged as a serious pest issue for Australia. Many new
populations have appeared across <strong>the</strong> Rangel<strong>and</strong>s as stock from deer farms are
released or escape. But deer provide a unique opportunity for cost-effective action as
most <strong>of</strong> <strong>the</strong> new populations can be eradicated if action is taken soon.
Deer were released at many sites in <strong>the</strong> nineteenth century, but usually <strong>the</strong>y failed to
survive, <strong>and</strong> those that did survive rarely prospered, usually remaining near <strong>the</strong>ir site
<strong>of</strong> introduction (Wilson et al. 1992). Deer are attractive, <strong>and</strong> <strong>the</strong> convenient
perception has arisen that unlike o<strong>the</strong>r <strong>feral</strong> <strong>animals</strong>, <strong>the</strong>y do not multiply or cause
harm. In his ground-breaking book about pests, They All Ran Wild, Eric Rolls claimed
that ‘Deer have done no noticeable damage in Australia’ (Rolls 1969). The Bureau <strong>of</strong>
Rural Resources book, Pest Animals in Australia (Wilson et al. 1992) also remains
silent about deer damage to <strong>the</strong> environment.
But deer are harmful <strong>and</strong> <strong>the</strong>ir numbers in Australia are exploding. Recently
published <strong>and</strong> authoritative books (Strahan 1995, Harrison 1998) assert that Australia
has only one population <strong>of</strong> chital deer, found near Charters Towers, when in truth
<strong>the</strong>re are at least 28 populations spread across four states, many within <strong>the</strong>
Rangel<strong>and</strong>s. This information comes from Moriarty (2004), who recently surveyed
government l<strong>and</strong> managers. He documented 65 red deer populations in place <strong>of</strong> <strong>the</strong>
four mentioned in recent books (including Strahan 1995), contradicting <strong>the</strong> claim by
Wilson et al. (1992) that ‘There is evidence that <strong>the</strong> range <strong>of</strong> … red deer has
contracted due to clearing <strong>of</strong> suitable habitat <strong>and</strong> hunting.’ Moriarty concluded that
‘Wild deer in Australia have moved from a minor component <strong>of</strong> <strong>the</strong> Australian biota
to one that is now widespread.’ Moriarty underestimated <strong>the</strong> deer population,
overlooking several populations recorded during a Queensl<strong>and</strong> survey (Jesser 2005).
Small deer herds in thick vegetation are easily overlooked (Jesser pers. comm.)
Evidence is also mounting to show that deer cause serious ecological <strong>and</strong>
environmental harm. The Scientific Committee <strong>of</strong> <strong>the</strong> New South Wales National
Parks <strong>and</strong> Wildlife Service supports a proposal to list <strong>feral</strong> deer damage as a key
threatening process <strong>impact</strong>ing upon vulnerable or endangered species, populations <strong>of</strong>
ecological communities (Jesser 2005). The red deer appears on <strong>the</strong> IUCN list <strong>of</strong> 100
<strong>of</strong> <strong>the</strong> World’s Worst Invasive Alien Species, largely because <strong>of</strong> <strong>the</strong> harm it does in
New Zeal<strong>and</strong>.
The explosion in deer numbers is largely a consequence <strong>of</strong> deer farming (Section 3),
an industry that grew rapidly during <strong>the</strong> 1980s (Jesser 2005). Deer were trapped from
<strong>feral</strong> populations <strong>and</strong> used as breeding stock. According to <strong>the</strong> Rural Industries
Research <strong>and</strong> Development Corporation (2000), <strong>the</strong> number <strong>of</strong> farmed deer rose
annually by about 25 percent up until <strong>the</strong> early 1990s. Deer periodically escape
through inadequate fences (Moriarty 2004). The market for <strong>the</strong>ir products crashed in
<strong>the</strong> early 1990s <strong>and</strong> many deer were liberated when <strong>the</strong> cost <strong>of</strong> feeding <strong>the</strong>m rose
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