DARLING RIVERINE PLAINS BIOREGION Background Report

More documents

Recommendations

Info

16/08/02 Darling Riverine Plains Bioregion Background Report of the recorded species are introduced (Thoms et al. 1995). Most of the native species are carnivorous, eating crustaceans, insects and other fish. Nematalosa erebi (bony herring) is herbivorous and some other species are omnivores. Two distinct food chains support fish production in the Darling River: Nematalosa erebi feed on the algal/bacterial/fungal biofilms on riverbanks, snags, rocks and the algae attached to aquatic plants. Nematalosa erebi are then a food source for the predator species such as Macquaria ambigua (golden perch) and Maccullochella peelii (Murray cod); and plant litter washed into the river is consumed by midge larvae and shrimps that are in turn preyed upon by small and medium-sized fish. Many terrestrial vertebrates rely on these species as they form part of the total food web of wetland habitats. Fifteen species of fish have been recorded in the Macquarie Marshes, two of which are introduced. The native species include Nematalosa erebi, Macquaria ambigua, Melanotaenia fluviatilis (rainbow fish), Retropinna semoni (Australian smelt) and Hypseleotris klunzingeri (western carp-gudgeon). Introduced species are Cyprinus carpio (European carp) and Gambusia holbrooki (gambusia). Diversity and abundance of native fish species is low and appears to be in decline, with species like Tandanus tandanus (catfish) once being common but now rarely seen (Harris & Gehrke 1997). The fish diversity and relative abundance in the ephemeral wetlands of the Narran Lakes differs from that in the Macquarie Marshes. Five species were recorded by surveys of Clear Lake, with a high abundance of Macquaria ambigua being recorded (NPWS 2000a). Seven fish species were predicted to occur but were not recorded in surveys of the Darling catchment (Harris & Gehrke 1997). One of these, Hyrtl’s tandan (Neosilurus hyrtlii), probably only occurs in the Paroo system, which is not part of the DRP, and another, the dwarf flathead gudgeon (Philypnodon sp 1), is only known from the Bathurst area, also outside the bioregion. The other unrecorded species were Ambassis agassizii (olive perchlet), Craterocephalus amniculus (Darling River hardyhead), Mogurnda adspersa (purple-spotted gudgeon), Galaxias rostratus (Murray jollytail) and Maccullochella macquariensis (trout cod). 6.2.2 Species of conservation concern Three fish species known from the Darling region have been listed under Schedules 3 and 5 of the Fisheries Management Act (FMA) 1994, and two of these species are also listed on the EPBC Act (Table 6.2). The western populations of two species within the DRP are listed as endangered populations under Schedule 4 of the FMA 1994. Reasons for listing of species under this Act include habitat changes due to agricultural practices, spawning failures due to cold water releases from dams, predation by, and competition with, introduced species such as Perca fluviatilis and Gambusia holbrooki, and construction of barriers to migration and recolonisation (FSC, 2001e). Five species are also considered to be of concern in New South Wales by Fletcher and McVea (2001). 114
16/08/02 Darling Riverine Plains Bioregion Background Report Table 6.2 Fish species of conservation concern within the DRP (Harris & Gehrke 1997; Harris 1995) Family Scientific Name Common Name Catchment Status Atherinidae Craterocephalus fluviatilis Murray hardyhead Recorded N, M E FMAct, VEPBC Percichthyidae Maccullochella macquariensis trout cod Predicted *E FMAct Terapontidae Bidyanus bidyanus silver perch G, N, M, D, V FMAct, IUCNV B-D Ambassidae Ambassis agassizii olive perchlet M CC1 Eleotridae Philypnodon grandiceps flathead gudgeon M CC1 Galaxiidae Gadopsis marmoratus river blackfish G, N, C, M CC2 Percichthyidae Maccullochella peelii Murray cod G, N, M, D, CC3 B-D Plotosidae Tandanas tandanas freshwater catfish G, N, M, B-D CC4 Key IUCNV = Classified as vulnerable under IUCN Red List Classifications (Fletcher and McVea 2001) VEPBC = Listed as vulnerable under the Environment Protection and Biodiversity Conservation Act, 1999 E FMAct = Listed as endangered under Schedule 3 of the Fisheries Management Act, 1994 an asterix denotes that the species is also listed as endangered under the Environment Protection and Biodiversity Conservation Act, 1999 V FMAct = Listed as vulnerable under Schedule 5 of the Fisheries Management Act, 1994 CC1 = of conservation concern due to reduced distribution and abundance inland (Fletcher and McVea 2001) CC2 = of conservation concern due to susceptibility to increased sediment load (Fletcher and McVea 2001) CC3 = of conservation concern due to reduced and fragmented distribution (Fletcher and McVea 2001) CC4 = of conservation concern due to scarcity in many inland habitats (Fletcher and McVea 2001) G = Gwydir River Catchment N = Namoi River Catchment C = Castlereagh River Catchment M = Macquarie River Catchment D = Darling River Catchment B-D = Barwon-Darling River The distribution and population size of many native fish species within the Murray-Darling system have contracted markedly as a result of changes in the rivers (Morton et al. 1995). Threats in this river system include river diversion, over-fishing, water quality (salinity, eutrophication) and the impact of introduced species, particularly Cyprinus carpio, Perca fluviatilis (redfin perch) and Gambusia holbrooki. The significant change in the natural pattern of high and low flows has also had an impact on the two fundamental food webs in the system. Biofilms on riverbanks are now constrained to a single narrow strip, rather than a broad band, because river heights are tightly controlled. Significant quantities of plant litter now lie unused on the floodplain and in anabranches for much longer periods. River flow diversion also creates another, little acknowledged, problem with many small fish being sucked from the river into irrigation systems and lost (Harris 1995). The construction of weirs and dams has had a significant effect on the life cycle of many species. Some species spawn in one part of the river system, use a different part as a nursery area and then disperse into a third area for growth into adults. Macquaria ambigua spawn during floods in lowland reaches of rivers, the young move into the floodplain or river-margin nurseries and finally travel upstream in river channels. Maccullochella peelii (Murray cod) make upstream spawning migrations using anabranches and flood-runners and then make a precise homing migration to their original territory. These fish therefore require the survival of each of these habitats and the maintenance of free passage between them. The scale of 115
Page 1 and 2:
DARLING RIVERINE PLAINS BIOREGION B
Page 3 and 4:
For more information data contact t
Page 5 and 6:
3.2 Vegetation Mapping and Descript
Page 7 and 8:
10 APPENDICES 166 A CLIMATIC DATA B
Page 9 and 10:
List of Maps Chapter 1 Map 1 Locati
Page 11 and 12:
PROJECT SUMMARY This report forms p
Page 13 and 14:
abbits are listed as key threatenin
Page 15 and 16:
16/08/02 Darling Riverine Plains Bi
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
ainfall (mm) 900 800 700 600 500 40
Page 33 and 34:
Page 35 and 36:
1500 1000 500 0 -500 -1000 -1500 -2
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Page 61 and 62:
Page 63 and 64: 16/08/02 Darling Riverine Plains Bi
Page 113: 16/08/02 Darling Riverine Plains Bi
Page 133 and 134: Initial Phase Assessment Phase 16/0
Page 165 and 166:
Page 167 and 168:
Appendix A: Mean Monthly Rainfall a
Page 169 and 170:
80 70 60 50 40 30 20 10 0 25 20 15
Page 171 and 172:
Major Rangetype Rangetype Physiogra
Page 173 and 174:
Appendix C : Native Flora Other Tha
Page 175 and 176:
Family Scientific Name Common Name
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Page 183 and 184:
Page 185 and 186:
Page 187 and 188:
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
Page 197 and 198:
Page 199 and 200:
Page 201 and 202:
Page 203 and 204:
Family Scientific Name cretica Comm
Page 205 and 206:
Page 207 and 208:
APPENDIX E: Fauna Other than Those
Page 209 and 210:
Common Name Scientific Name No Reco
Page 211 and 212:
Page 213 and 214:
Page 215 and 216:
Page 217 and 218:
Common 1983 1984 1985 1986 1987 198
Page 219 and 220:
Common Name 1983 1984 1985 1986 198
Page 221 and 222:
Taxa No Records Dataset Class Arach
Page 223 and 224:
Taxa No Records Dataset Family Hebr
Page 225 and 226:
Taxa No Records Dataset Tabanidae s
Page 227:
Taxa No Records Dataset Berosus sp
show all

DARLING RIVERINE PLAINS BIOREGION Background Report

Create successful ePaper yourself

Delete template?

Save as template?