Barrow Island (26474)
Australia, Australasia
Site overview
KBA status: confirmed
Global KBA criteria: A1b, D1a
Year of last assessment: 2009
National site name: Barrow Island
Central coordinates: Latitude: -20.7878, Longitude: 115.3990
System: marine, terrestrial
Elevation (m): 0 to 65
Area of KBA (km2): 234.06031
Protected area coverage (%): 99.86
KBA classification: Global
Legacy site: Yes
Site details
Site description: The IBA consists of the whole 235 km² Barrow Island, as the whole island is listed as a Nature Reserve and threats from invasive species must be managed on a whole-island basis. Barrow is 60 km off the Pilbara coast of Western Australia. It is a limestone island with a hot, arid climate and a mean rainfall of about 320 mm pa. Most of the island is low and gently undulating, but on the west coast there are gullies, cliffs and sandy beaches. Hummock grassland dominates the landscape and provides habitat for Spinifexbirds and White-winged Fairy-wrens. Although shorebirds are concentrated in the south-east and south of Barrow Island, significant numbers are present around the entire island except for the 'Upper West' section (Bamford and Bamford 2005).
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that meets the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs.
Additional biodiversity: The Barrow Island subspecies of the White-winged Fairy-wren Malurus leucopterus edouardi is endemic, listed as vulnerable (Garnett and Crowley 2000), protected by the Federal EPBC Act, genetically distinct from the mainland Malurus leucopterus leuconotus (Driskell et al. 2002) and has a population of around 7500 birds (Bamford and Bamford 2005). 1708 Common Terns counted in November 2003 and 7300 Roseate Terns counted in September 2004 are more than the 1% of the biogeographic population but it is not known whether the island regularly supports these numbers. A count of 83 Sooty Oystercatcher represents 1.1% of the known population of the distinctive northern race (ophthalmicus) of the species. Counts of Sanderling, Greater Sand Plover and Lesser Sand Plover during the southward migration period (September to November) met the staging criterion (0.25% of a species’ biogeographic population) of the Ramsar Convention. Counts of 4000 Bridled Terns around Double Island in November 2003 may also be locally significant for this species (Bamford and Bamford 2005). Non-bird biodiversity: Barrow Island has several mammal taxa listed as threatened and numerous endemic subterranean animals (troglobites and stygobites), some of which are listed as threatened. One endemic troglobitic snake species (the only troglobitic snake in the world) and one endemic skink subpecies also occur on the island. The beaches are regionally-significant rookeries for green turtles (west coast) and flatback turtles (east coast).
Other site values: Barrow Island Nature Reserve is Class A Reserve 11648 for 'Conservation of Flora and Fauna' vested in the Conservation Commission of Western Australia and managed by the Department of Environment and Conservation. A petroleum lease, owned by Chevron Australia, covers the whole island. Access is limited because of Petroleum Production Lease.
Habitats
Land use: nature conservation and research (95%) | urban/industrial/transport (5%)
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Marine Intertidal | 5 | |
| Grassland | 95 |
Threats
Summary of threats to biodiversity at KBA: Disturbance to the shorebirds from people and infrastructure development needs to be minimised. To conserve the terrestrial species, the quarantine management system needs improving, including intensive biological monitoring to detect introduced species before they become widespread.
| Threat level 1 | Threat level 2 | Threat level 3 | Timing |
|---|---|---|---|
| Invasive & other problematic species, genes & diseases | Invasive non-native/alien species/diseases | Unspecified species | Ongoing |
| Natural system modifications | Fire & fire suppression | Increase in fire frequency/intensity | Ongoing |
| Residential & commercial development | Commercial & industrial areas | Only in the future | |
| Energy production & mining | Mining & quarrying | Only in the future | |
| Energy production & mining | Oil & gas drilling | Ongoing | |
| Human intrusions & disturbance | Recreational activities | Ongoing |
Additional information
References: Bamford, M.J. and Bamford, A.R. (2005) Technical Report: Avifauna. Technical Appendix C3 in the draft EIS/ERMP for the proposed Gorgon development. http://www.gorgon.com.au/ 03-man_environment/EIS/Technical Appendix C3. Driskell, A.C., Pruett-Jones, S., Tarvin, K.A. and Hagevik, S. (2002) Evolutionary relationships among blue-and black-plumaged popuklations of the white-winged fairy-wrens (Malurus leucopterus). Australian Journal of Zoology 50(6): 581-595. Garnett, S.T. and Crowley, G. M. (2000) The Action Plan for Australian Birds 2000. Canberra: Environment Australia. Sedgewick, E.H. (1978) A population study of the Barrow Island avifauna. Western Australian Naturalist 14: 85-108.
Contributors: Thanks to Andrew Burbidge as compiler of the nomination and for comments received from Mike Bamford and Cheryl Gole.