In South Australia COVER
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The State of Biological Resources in South Australia COVER: The tiny Feathertail Glider Acrobates pygmaeus is confined to well wooded areas in the State's South East. Active mostly at night, it is capable of gliding between trees up to 20 metres apart in search of its diet of nectar, blossoms, sap and small invertebrate animals. 7?0í3ib.v /VaRwoad THE STATE OF BIOLOGICAL RESOURCES IN SOUTH AUSTRALIA A contribution toward improving our understanding of the South Australian environment Graeme Greenwood and Elizabeth Gum Conservation Projects Branch Department of Environment and Planning 1986 (second printing 1988) ISBN 7243 88397 CONTENTS Page List of Figures List of Tables List of Appendices v SUMMARY vii CONCLUSIONS xiv 1. TERRESTRIAL ENVIRONMENT 1.1 BACKGROUND 1 1.1.1 The Agricultural Area 1.1.2 Marginal and Arid Lands 1.2 TERRESTRIAL FLORA 24 1.2.1 Vascular Plants 24 1.2.2Non vascular Plants 33 36 1.3 TERRESTRIAL FAUNA 1.3.1 Vertebrates 36 1.3.2 Invertebrates 43 2. INLAND WATER ENVIRONMENT 52 2.1 BACKGROUND 52 2.2 INLAND WATER FLORA 65 2.3 INLAND WATER FAUNA 67 Page 2.3.1 Vertebrates 70 2.3.2 Invertebrates 74 3. MARINE ENVIRONMENT 81 3.1 BACKGROUND 81 3.1.1 Seas and Their Significance to South Australia 81 3.1.2 The Marine Biota of South Australia 86 3.2 MARINE FLORA 93 3.2.1 Seagrasses 94 3.2.2 Seaweeds 99 3.2.3 Phytoplankton 100 3.2.4 Mangroves 101 3.3 MARINE FAUNA 106 3.3.1 Vertebrates 107 3.3.2 Invertebrates 111 4. ANALYSIS OF FINDINGS AND RECOMMENDATIONS 116 4.1 FLORA 116 4.2 FAUNA 120 APPENDICES 128 BIBLIOGRAPHY 165 i LIST OF FIGURES Page Figure 1.1 Level of disturbance resulting from European 2 Settlement Figure 1.2 Current land occupation of South Australia 5 Figure 1.3 Vegetation clearance applications monthly status 7 Figure 1.4 Increase in National Parks, Conservation Parks, 10 Recreation Parks, and Game Reserves in South Australia, 1892 -1985 Figure 1.5 Native vegetation in the central and southern Mt 13 Lofty Ranges in 1945 Figure 1.6 Native vegetation in the central and southern Mt 14 Lofty Ranges in 1968 Figure 1.7 Native vegetation in Kangaroo Island in 1945, 1958, 15 1969 and 1981 Figure 1.8 Changes in arid land shrub density on Frome Downs 20 Cattle Station Figure 1.9 Changes in an arid zone plant community following removal of grazing 21 Figure 1.10 Reference map of regions 26 Figure 1.11 Numbers of plant species presumed extinct in each region of South Australia 28 Figure 1.12 Number of endangered plant species in each region 28 of South Australia Figure 1.13 Areas of wetland in South Australia 56 11 Page Figure1.14 Primary productivity of South Australian ecosystems 91 Figure1.15 Major features of the coastal zone 92 Figure1.16 Extent of seagrass decline off Adelaide metropolitan coast 97 Figure1.17 Coastal wetlands of South Australia 103 Figure1.18 Trends in the clearance of native vegetation in the Agricultural Regions 117 Figure1.19 Relative abundance of plant associations by region, and their representation in NPWS reserves 119 Figure1.20 Conservation Status of South Australia's 165 plant 119 association Figure1.21 Conservation status of South Australian vascular plant species 121 Figure1.22 Taxonomic status of non vascular plants in South Australia 121 Figure1.23 Status and diversity of the native South Australian vertebrate fauna 123 Figure1.24 Taxonomic status of invertebrate animals in South Australia 126 111 LIST OF TABLES Page Table1.1 Modification to natural vegetation 3 Table1.2 Extent of native vegetation clearance in South 4 Australia's agricultural areas in 1974 and 1985 Table1.3 Changes in numbers of arid land shrubs on a 2140 m transect at Frome Downs Cattle Station, South Australia, in the 45 year period after cattle grazing commenced in 1929 22 Table1.4 Number of plant species within each threat category for South Australia 27 Table1.5 Plant species conserved in South Australia 30 Table1.6 Conservation status of plant associations in South Australia 31 Table1.7 Most threatened plant association categories in each environmental province 32 Table1.8 Status of terrestrial mammals in South Australia 38 Table1.9 Status of birds in South Australia 42 Table1.10 Summary of the status of South Australian terrestrial vertebrates 44 Table1.11 Major groups of terrestrial invertebrates and current state of knowledge 45 Table1.12 Current status of wetlands in South Australia 58 Table1.13 Unconserved wetlands of particular significance in South Australia 63 iv Page Table 1.14 Status of wetland birds in South Australia 72 Table 1.15 Status of inland water fishes in South Australia 74 Table 1.16 Freshwater invertebrates monitored by the State Water Laboratory of the Engineering and Water Supply Department since 1978 78 Table 1.17 Major invertebrate groups of inland waters and current state of knowledge 79 Table 1.18 Main types of marine habitat and associated biota 88 Table 1.19 Engineering and Water Supply Department reports containing references to South Australian seaweed and /or seagrasses 100 Table 1.20 Mangrove sites considered to be under stress in South Australia 106 Table 1.21 Status of marine mammals in South Australia 110 Table 1.22 Commercially exploited marine invertebrates in South Australia 112 Table 1.23 Extent of knowledge of marine invertebrates 114 V LIST OF APPENDICES Page Appendix 1 State Herbarium regions of South Australia 129 Appendix 2 Coding system for native flora and fauna 130 Appendix 3 Native vegetation species presumed extinct in South Australia threats and former occurrence 134 Appendix 4 Endangered native vegetation species in South Australia threats and occurrence 135 Appendix 5 Rare or threatened native plants in South Australia 137 Appendix 6 Threatened plant species of the Mt Lofty Ranges and Kangaroo Island regions of South Australia 143 Appendix 7 South Australian rare or threatened plants in cultivation at Botanic Gardens of Adelaide 144 Appendix 8 Rare plants in cultivation at Black Hill Native Flora Research Unit 146 Appendix 9 Research projects underway at Black Hill Native Flora Research Unit dealing with rare or endangered species of native plants 148 Appendix 10 An index of conservation priorities for plant associations categories not conserved or poorly conserved in South Australia 149 Appendix 11 Environmental provinces of South Australia 153 Appendix 12 Mammals 154 Appendix 13 Birds 167 Vi Page Appendix14 Reptiles and Amphibians 189 Appendix15 Freshwater fishes 201 Appendix16 Marine fishes 206 vii SUMMARY The purpose of this report is to describe, evaluate and explain the current condition and conservation status of South Australia's indigenous biological resources. It forms part of a major study of the state of the South Australian environment. It excludes introduced cultivated plants and domestic animals, other than those which now exist in the wild. For practical purposes the report is divided into three sections, each dealing with the biota of a major habitat type. These are: 1. The terrestrial, or land environment. 2. The inland water environment, including saline and temporary water bodies, and 3. The marine environment. The report examines each of these in terms of: the current state of knowledge the availability and applicability of data the current condition of each major habitat type, based on existing knowledge and data, and the conservation status of, and the legislative protection afforded to the State's biological resources. 1. TERRESTRIAL ENVIRONMENT a) The State of Knowledge. Two components of the terrestrial biota are well documented. These are the flowering plants, and the birds and mammals. All have been studied historically, with survey reports, specific and general accounts being widely available. Trends for species and communities generally can be discerned. viii For the lower plants including mosses, liverworts, lichens and fungi, the reptiles, and invertebrate animals generally, there is a paucity of current information and an overall lack of historical data. b) Availability and Application of Data. Most information used is in published form. The existence of maps and aerial photographs over time sequences has allowed data to be compiled for the quantitative assessment of loss rates for native vegetation in the agricultural regions of the State. In the arid northern part of the State however, no such data base exists and inferences have been drawn from the small number of documented experimental case studies. Data for the birds and mammals are from a variety of published and unpublished sources, comprising documented fact and the informed opinions of individuals actively researching particular groups in South Australia. Where information on other groups is available, it is not yet possible to apply it because of incompleteness, a lack of historical perspective, or both. c) State of the Terrestrial Environment Biota. The information available indicates: That natural vegetation in the agricultural region has declined in area by approximately 80% since European settlement, and the trend towards further clearance is continuing. In the arid zone the standing crop of native vegetation has declined significantly. A combination of habitat loss, and the competition from introduced plants and animals has resulted in extinction for 28 native mammal and 5 bird species. In addition 6 flowering plant species are presumed to be extinct on a national level. Many more plants are extinct within South Australia, but no statistics are available to enable an accurate assessment to be made of the situation. Research in this area is vital to provide basic data upon which to base management of the State's flora. ix It is possible that less conspicuous components of the biota have already become extinct or are likely to do so without ever coming to the attention of either the general or scientific communities.