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esources. Significant investment in carp control research <strong>and</strong> development is made in Australia. Several potential control techniques have been suggested; however current control efforts generally rely on manual extraction, poisoning, exclusion <strong>and</strong> a commercial fishery. Distribution Carp have become <strong>the</strong> most abundant large freshwater fish in Australia. They are widely distributed throughout south-eastern Australia <strong>and</strong> dominate fish communities throughout <strong>the</strong>ir range. They occur all through <strong>the</strong> Murray-Darling Basin <strong>and</strong> inl<strong>and</strong> waterways <strong>of</strong> South Australia, including <strong>the</strong> Lake Eyre Basin. A survey by New South Wales Fisheries has shown that carp consist <strong>of</strong> over 80 per cent <strong>of</strong> total fish biomass within much <strong>of</strong> <strong>the</strong> Murray-Darling basin, <strong>and</strong> as high as 96 per cent in some regions. The occurrence <strong>of</strong> carp in temporary or intermittent wetl<strong>and</strong>s can be highly sporadic <strong>and</strong> dependent upon <strong>the</strong> drying <strong>and</strong> wetting cycle (Gehrke et al. 1999). Carp have <strong>the</strong> potential to spread to many more <strong>of</strong> Australia’s waterways <strong>and</strong> could become even more widespread. The preferred habitat <strong>of</strong> carp consists <strong>of</strong> warm, still water with a silty substrate that enables <strong>the</strong>m to easily forage for food. Many <strong>of</strong> <strong>the</strong> inl<strong>and</strong> aquatic habitats in <strong>the</strong> sou<strong>the</strong>rn Rangel<strong>and</strong>s have been disturbed by human activities such river flows alteration/regulation, nutrients enrichment <strong>and</strong> streamside vegetation clearance, creating idea environments for carp. Their broad environmental tolerances, including <strong>the</strong> ability to thrive in highly polluted or low oxygen water, allow <strong>the</strong>m to prosper in <strong>the</strong>se altered habitats. Impacts Carp in Australia now have a role as predators, prey, competitors <strong>and</strong> habitat modifiers that affect o<strong>the</strong>r species <strong>and</strong> ecological processes. Most perceptions <strong>of</strong> environmental damage by carp focus on <strong>the</strong>ir potential to <strong>impact</strong> wetl<strong>and</strong>s reduce water quality <strong>and</strong> harm native fish populations. Although carp are <strong>of</strong>ten regarded as having a harmful effect on aquatic habitats <strong>and</strong> native species, <strong>the</strong>re is little information on <strong>the</strong> overall <strong>impact</strong> <strong>the</strong>y have. Limited research on environmental effects <strong>of</strong> carp has been undertaken, however many <strong>of</strong> <strong>the</strong> <strong>impact</strong>s are unclear because <strong>the</strong>y can be caused by o<strong>the</strong>r anthropogenic activities. Carp predominantly feed by sucking in mouthfuls <strong>of</strong> mud <strong>and</strong> silt from <strong>the</strong> banks <strong>and</strong> bottom <strong>of</strong> <strong>the</strong>ir habitat <strong>and</strong> straining out <strong>the</strong> inedible sediment with <strong>the</strong>ir gill rakers <strong>and</strong> muscular s<strong>of</strong>t palate. Food is also sucked from aquatic vegetation in a similar manner. There is clear evidence that carp increase water turbidity <strong>and</strong> damage many aquatic plants <strong>and</strong> some evidence that <strong>the</strong>y increase water nutrient levels through <strong>the</strong>ir feeding behaviour. Such damage can threaten endangered species <strong>and</strong> alter ecosystem function. Carp have been suggested as one cause in <strong>the</strong> decline <strong>of</strong> several threatened species however <strong>the</strong>se have not inhabited waters <strong>of</strong> <strong>the</strong> Rangel<strong>and</strong>s (Koehn et al. 2000). Impacts on native fish fauna are less well documented, even though carp <strong>of</strong>ten dominate fish assemblages. Declines in native fish populations in many areas occurred prior to <strong>the</strong> introduction <strong>of</strong> carp populations. Carp may simply be taken <strong>the</strong> place <strong>of</strong> native fish that have already been displaced. Carp compete with native species for food <strong>and</strong> habitat space such as spawning sites. Since carp spawn at lower temperatures than many native species, <strong>the</strong>y spawn before many species <strong>and</strong> may exclude smaller species from <strong>the</strong>ir preferred spawning areas in vegetated habitats. A degree <strong>of</strong> dietary overlap occurs between carp <strong>and</strong> native species. Despite <strong>the</strong> strong likelihood <strong>of</strong> competition existing, <strong>the</strong>re is currently no 58
documented evidence <strong>of</strong> native fish species being displaced by carp in Australia (Koehn et al. 2000). Habitat use by carp <strong>and</strong> native species do overlap, with both using snags <strong>and</strong> areas <strong>of</strong> slow flowing water (Koehn & Nichol 1998). Ano<strong>the</strong>r pressure on habitat use for native species may be behavioural pressure exerted by large schools <strong>of</strong> large carp, which may force smaller native fish from <strong>the</strong>ir preferred habitat areas. The high biomass reported for carp may have <strong>the</strong> effect <strong>of</strong> physical exclusion from habitats for native species (Koehn et al. 2000). A number <strong>of</strong> parasites <strong>and</strong> disease organisms have been identified in carp. Those currently known to occur also in native fish <strong>and</strong> which pose a risk to native species include: <strong>the</strong> fungus Saprolegnia; <strong>the</strong> protozoans Myxobolus, Trichodina, Ichthyobodo, Cheilodonella, Ichthyophthirius <strong>and</strong> Apiosoma; <strong>the</strong> monogeneans Dactylogyrus <strong>and</strong> Gyrodactylus; <strong>the</strong> cestode Bothriocephalus; <strong>and</strong> <strong>the</strong> copepod Lernaea (Koehn et al. 2000). 3.7.41 English Perch (Perca fluviatilis) Summary A fish <strong>of</strong> limited distribution within <strong>the</strong> Rangel<strong>and</strong>s; present across <strong>the</strong> sou<strong>the</strong>rn half <strong>of</strong> New South Wales <strong>and</strong> south-eastern waterways <strong>of</strong> South Australia. This piscivorous fish can have significant localised <strong>impact</strong> on native species through predation as well as direct competition for food <strong>and</strong> habitat resources. Currently no <strong>management</strong> is undertaken. Distribution In <strong>the</strong> Rangel<strong>and</strong>s, English perch occur in <strong>the</strong> south-eastern waterways <strong>of</strong> South Australia <strong>and</strong> <strong>the</strong> sou<strong>the</strong>rn half <strong>of</strong> New South Wales in <strong>the</strong> Murray-Darling Basin. Their distribution is restricted by an aversion <strong>of</strong> high water temperatures <strong>and</strong> fast flowing waters. They prefer <strong>the</strong> still waters <strong>of</strong> lagoons, creeks <strong>and</strong> lakes, particularly where structured habitat such as submerged timber or aquatic vegetation exists. The distribution <strong>of</strong> English perch appears stable due to natural barriers created by water temperatures <strong>and</strong> velocities. Impacts English perch are thought to have a significant <strong>impact</strong> on native fish species in many regions. Their piscivorous nature <strong>and</strong> <strong>the</strong>ir tendency to form large populations are believed to be detrimental to native species through direct competition for food <strong>and</strong> habitat resources <strong>and</strong> predation <strong>of</strong> small fish (Arthington & Blühdorn 1995). Fragmentation <strong>and</strong> decline <strong>of</strong> native species has been directly correlated with English perch (Hutchinson 1991). Yet English perch do not have detrimental effect on native fish in all waterways. When food <strong>and</strong> habitat resources are abundant, native species have been able to successfully co-exist with perch, despite some predation pressure (Pen & Potter 1992). However, in waters <strong>of</strong> low productivity where competition for resources is intense, English perch represent a substantial threat <strong>and</strong> have <strong>the</strong> greatest <strong>impact</strong> (Arthington & McKenzie 1997). In regions <strong>of</strong> <strong>the</strong> Murray River in Victoria, it has been observed that depleted populations <strong>of</strong> native fish did not increase until perch numbers decreased (McKay 1984). English perch are also a known carrier <strong>of</strong> <strong>the</strong> epizootic haematopoietic necrosis virus which has shown to be highly pathogenic for 59
Page 1:
Review of<
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Contributors Andrew Norris Pest Ani
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3.7.36 Common Myna (Acridot
Page 8 and 9:
Table of figures F
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Section 2 Introduction Feral <stron
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Amanda Dimmock, QD
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Section 3 A status review o
Page 16 and 17: 3.4 Birds Thirteen (or 14) species
Page 18 and 19: Information on the
Page 20 and 21: Summary A rodent that contributes t
Page 22 and 23: Dingoes can become a threat to wild
Page 24 and 25: The significance of</strong
Page 26 and 27: macropods and b<st
Page 28 and 29: ^Lasiorhinus krefftii North
Page 30 and 31: Perceived threat Geopsittacus occid
Page 32 and 33: conservation areas. It is less clea
Page 34 and 35: Table 8 Rare species found in <stro
Page 36 and 37: Competition Several examples are re
Page 38 and 39: In truth, camels do substantial dam
Page 40 and 41: the Tanami. Buffal
Page 42 and 43: The situation today Buffalo numbers
Page 44 and 45: qualify under IUCN criteria as enda
Page 46 and 47: 3.7.16 Goat (Capra hircus) Summary
Page 48 and 49: Drakonorchis drakeoides Hinged Drag
Page 50 and 51: 3.7.19 Red Deer (Cervus elaphus) Su
Page 52 and 53: Impacts Much is known about <strong
Page 54 and 55: Distribution Ostriches have won <st
Page 56 and 57: nest in tree hollows along
Page 58 and 59: Distribution The skylark is found i
Page 60 and 61: Distribution The blackbird is wides
Page 62 and 63: Land, and<
Page 64 and 65: have been translocated to o
Page 68 and 69: many native species (Clarke et al.
Page 70 and 71: spread across the
Page 72 and 73: Section 4 Legislative framework 4.1
Page 74 and 75: protection, as long as it falls wit
Page 76 and 77: Native Vegetation Conservation Act
Page 78 and 79: ehabilitate existing native vegetat
Page 80 and 81: suppression, which is the</
Page 82 and 83: al. 1986, 1987). The use of
Page 84 and 85: 5.1.4 Mustering Commercial musterin
Page 86 and 87: etal. (1997) found that many native
Page 88 and 89: the vaccine <stron
Page 90 and 91: Where possible, integration <strong
Page 92 and 93: strategy, relative cost-effectivene
Page 94 and 95: Fencing Feral buffalo have a reputa
Page 96 and 97: 5.3 Management of
Page 98 and 99: Summary of <strong
Page 100 and 101: time comes for the
Page 104 and 105: Individual tracking Tracking is a l
Page 106 and 107: SA - Currently cats are not widely
Page 108 and 109: Method of control
Page 110 and 111: Aerial shooting Aerial shooting can
Page 114 and 115: 80% of export was
Page 116 and 117:
ensuring effective treatment <stron
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the lower cost, wi
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5.8 Management of
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conservation value rathe</s
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effort on the cont
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5.9 Management of
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follow transect lines, one kilometr
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as a refuge from predators. Removal
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Summary of <strong
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was completed it was the</s
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warren structure amenable to recolo
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Poisons Traditionally, strychnine,
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infected and steri
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of high priority.
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Method of control
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5.11 Management of
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technique can allow for cost-effect
Page 150 and 151:
Summary of <strong
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In South Australia, between 30 <str
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Summary of <strong
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% respondents 100% 90% 80% 70% 60%
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a) b) Figure 3. a) Extent o
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Figure 4 Response frequency for lik
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distribution of <s
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Section 7 Key problems and<
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• Goats degrading temperate woodl
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conservation problems in Europe <st
Page 170 and 171:
message that camels are a valuable
Page 172 and 173:
In the Koolatong R
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environmental degradation’ (Nor<s
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ecause dingo and d
Page 178 and 179:
Various control methods have been a
Page 180 and 181:
Pascale Taplin, an Indigenous L<str
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Lack of a Strategi
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eradicated after seeing the
Page 186 and 187:
In some situations, payment <strong
Page 188 and 189:
could have led to better protocols
Page 190 and 191:
Game hunting is a growing business,
Page 192 and 193:
Much as we might like it, t
Page 194 and 195:
conservation outcome. In such a sit
Page 196 and 197:
community consultation and<
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• Have the non-t
Page 200 and 201:
provide opportunities for strategic
Page 202 and 203:
Section 9 Priorities for investment
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contacted for exact locations <stro
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way. Achilles heel research should
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efficient in any given situation. R
Page 210 and 211:
west Queensland re
Page 212 and 213:
Crossland, MR, 199
Page 214 and 215:
Forsyth, DM, and P
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Lange, RT, and Gra
Page 218 and 219:
Morgan, LA and But
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Parkes, JP, 1990, Feral goat contro
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Van Rensberg, PJJ, Skinner, JD, <st
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Appendix A Ferals animals</
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Indigenous lands I
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Appendix B Stakeholder survey form
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222
Page 232 and 233:
224
Page 234 and 235:
226
Page 236 and 237:
Appendix C Database on past NHT fun
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Lachlan Rehabilitation of</
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Northern Territory
Page 242 and 243:
Cape York Ambiilmungu-Ngarra tradit
Page 244 and 245:
Wet Tropics Expansion and</
Page 246 and 247:
Avon Protecting and</strong
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