Research Library Technical Bulletins Research Publications 2004 An inventory and condition survey of the Pilbara region, Western Australia A M E van Vreeswyk K A. Leighton A L. Payne P Hennig Follow this and additional works at: https://researchlibrary.agric.wa.gov.au/tech_bull Part of the Agricultural and Resource Economics Commons, Agricultural Economics Commons, Agricultural Science Commons, Desert Ecology Commons, Environmental Education Commons, Environmental Health Commons, Environmental Indicators and Impact Assessment Commons, Environmental Monitoring Commons, Geology Commons, Geomorphology Commons, Natural Resource Economics Commons, Natural Resources and Conservation Commons, Natural Resources Management and Policy Commons, Physical and Environmental Geography Commons, Soil Science Commons, Sustainability Commons, Systems Biology Commons, and the Terrestrial and Aquatic Ecology Commons Recommended Citation van Vreeswyk, A M, Leighton, K A, Payne, A L, and Hennig, P. (2004), An inventory and condition survey of the Pilbara region, Western Australia. Department of Primary Industries and Regional Development, Western Australia, Perth. Technical Bulletin 92. This technical bulletin is brought to you for free and open access by the Research Publications at Research Library. It has been accepted for inclusion in Technical Bulletins by an authorized administrator of Research Library. For more information, please contact [email protected]. 54886 Ag Dept Cover 4/4/05 8:56 AM Page 1 Department of Agriculture Government of Western Australia An inventory and condition survey of the Pilbara region, Western Australia No. 92 A.M.E. Van Vreeswyk A.L. Payne K.A. Leighton P. Hennig 54886 00i-086 14/4/05 12:10 PM Page i An inventory and condition survey of the Pilbara region, Western Australia By: A.M.E. Van Vreeswyk, A.L. Payne, K.A. Leighton and P. Hennig Technical Bulletin No. 92 December 2004 Department of Agriculture 3 Baron-Hay Court SOUTH PERTH 6151 Western Australia ISSN 0083-8675 ©Chief Executive Officer, Department of Agriculture, Western Australia 2004 Front cover: Gregory Gorge on the Fortescue River i 54886 00i-086 14/4/05 12:10 PM Page ii The authors A.M.E. Van Vreeswyk, A.L. Payne and P. Hennig, Rangelands Program, Department of Agriculture, Western Australia and K.A. Leighton, Geographic Services Branch, Department of Land Information, Western Australia. Other contributors S.L. Johnson, Department of Environment, Western Australia and A. Longbottom, Department of Agriculture, Western Australia. Acknowledgments The authors wish to thank A.A. Mitchell for his specialist botanical skills and enthusiastic assistance in the field, R. Wetterings for providing essential logistical support, and P.T. Godden and A.F. MacDonagh for their contributions as navigators and for their work on map production. We also thank S. Zappelli for her work on map production. We thank our agency colleagues, particularly the soil surveyors who assisted us during field work, and arid zone botanists throughout Australia for identification of plant specimens. We acknowledge the people who provided constructive criticism on parts of this report. This survey could not have been conducted without the co- operation, advice and assistance of pastoralists throughout the area. Definition The Pilbara region, as used in this report, includes the following 1:250,000 map sheets: Balfour Downs, Marble Bar, Nullagine, Robertson, Roy Hill, Pt Hedland and Yarrie, and parts of the Collier, Dampier, Mandora, Mt Bruce, Newman, Onslow, Pyramid, Roebourne, Turee Creek, Yarraloola and Wyloo. National Library of Australia Cataloguing-in-Publication entry An inventory and condition survey of the Pilbara region, Western Australia. Bibliography ISBN 0 646 44349 6. 1. Pastures - Western Australia - Pilbara. 2. Rangelands - Western Australia - Pilbara. I. Van Vreeswyk, A. M. E. (Alexandra Margaretha Elizabeth), 1963- . II. Western Australia. Dept. of Agriculture. (Series : Technical Bulletin (Western Australia. Dept. of Agriculture) ; No. 92). 633.202099413 The Chief Executive Officer of the Department of Agriculture and the State of Western Australia accept no liability whatsoever by reason of negligence or otherwise arising from the use or release of this information or any part of it. ii 54886 00i-086 14/4/05 12:10 PM Page iii Contents Page Summary .................................................................................................................... 1 Introduction ............................................................................................................... 5 Review ......................................................................................................................... 11 A brief land use history...................................................................................... 13 Climate ............................................................................................................... 19 Geology and hydrogeology ............................................................................... 39 Declared plants and animals ............................................................................. 53 The survey .................................................................................................................. 59 Methodology....................................................................................................... 61 Geomorphology.................................................................................................. 70 Soils..................................................................................................................... 87 Vegetation ........................................................................................................... 109 Site type ecology ................................................................................................ 125 Land systems ...................................................................................................... 175 Resource condition............................................................................................. 385 Appendices .................................................................................................................. 401 1. Plant species lists (i) Plant species recorded in the survey area ..................................... 402 (ii) Common plants in the survey area ................................................ 422 2. Land system maps iii 54886 00i-086 14/4/05 12:10 PM Page iv iv 54886 00i-086 14/4/05 12:10 PM Page 1 Summary Scope of the survey 1. The area surveyed by field work during 1995, 1996, 1997 and 1999 covers about 181,723 km2 and includes the following 1:250,000 scale map sheets: the entire Balfour Downs, Marble Bar, Nullagine, Robertson, Roy Hill, Pt Hedland and Yarrie sheets, most of the Mt Bruce, Newman, Pyramid and Yarraloola sheets and small parts of the Collier, Dampier, Mandora, Onslow, Roebourne, Turee Creek and Wyloo sheets. Seven towns fall within the area, namely Pt Hedland in the north, Onslow and Pannawonica to the west, Wittenoom in the centre, Marble Bar and Nullagine in the centre east and Newman in the south-east. Several major river catchments occur in the survey area including the De Grey, Turner and Yule in the north, and the Fortescue and Robe in the west. All rivers are ephemeral and flow generally north-west to the Indian Ocean. 2. Pastoralism is the most extensive land use in the area. Forty-four pastoral leases fall wholly or partly within the survey area and collectively occupy about 105,240 km2 (58% of the area). Areas set aside for nature conservation at the time of survey covered approximately 16,629 km2 (9% of the area) consisting of the Karijini and Millstream-Chichester National Parks, the Mungaroona Range and Cane River Nature Reserves and the Meentheena pastoral lease which has been purchased by the Department of Conservation and Land Management (CALM), destocked and is to be incorporated into the conservation estate. The Aboriginal reserves of Abydos, Jigalong, Woodstock and Yandeyarra, and the special lease for Aboriginal use, Callawa, occupy about 9,740 km2 (5% of the area). Mining is an important land use which is largely confined to ironstone ranges and greenstone belts throughout the survey area. There are also large tracts of unallocated Crown land which account for about 48,840 km2 (27% of the area). The remaining 1% of the survey area is made up of town commons and various reserves. 3. This report provides a regional inventory and descriptive reference of land resources to accompany a land system map. The report includes reviews of background information such as land use history, climate, geology and hydrogeology, and declared plants and animals. Detailed accounts are then provided of survey methodology, geomorphology, soils, vegetation, site type ecology, land systems and resource condition (in terms of pastoral impact) of the survey area. A comprehensive plant species list is supplied as an appendix. 4. Resource condition statements are provided for the whole survey area, for each land system and for the major ecological site types. These are derived from 12,445 visual traverse assessments, which are shown on the accompanying land system map. Severely degraded and eroded areas have been mapped. 5. The report deals specifically with resource description and assessment, recognising the widespread impact of pastoralism on resources in the process. A companion report1 focusing on pastoral