Eighty Mile Beach (25147)
Australia, Australasia

Site overview

KBA status: confirmed

Global KBA criteria: A1a, A1c, B1, D1a

Year of last assessment: 2009

National site name: Eighty Mile Beach

Central coordinates: Latitude: -19.5785, Longitude: 120.8743

System: marine, terrestrial

Elevation (m): 0 to 10

Area of KBA (km²): 315.17785

Protected area coverage (%): 94.09

KBA classification: Global

Legacy site: Yes

Site details

Site description: Eighty Mile Beach is in the southern Kimberley, south of Broome. The IBA is defined as the intertidal flats and sandy beach between Cape Missiessy, 142 km south of Broome, to Cape Keraudren, 220 km further south. It lies immediately adjacent to the Mandora Marsh & Anna Plains IBA, but as only a few species of shorebird move regularly between the beach and plains, these are kept as separate IBAs (Oriental Plover and Little Curlew feed on the plains and sometimes use the beach as a hot-weather refuge). The climate is semi-arid monsoonal with a hot wet summer and a warm dry winter. Eighty Mile Beach is a long and relatively featureless beach with intertidal mudflats rich in benthic organisms. The beach is approximately 100 m wide and includes several irregular, muddy, microscale embayments, while the adjoining tidal mudflats vary from an estimated 1 to 5 km in width. Shorebirds are found along this entire stretch of coastline but are most concentrated where the mud-flats are widest. The IBA is included within the Eighty-mile Beach Ramsar site.

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: A count in 2001 indicated the wader population at Eighty Mile Beach numbered approximately 470,000 individuals (Minton et al 2003b) while another 150-200,000 use the site as a migration stop-over (DEWHA 2008). The beach regularly supports a few individuals of the near threatened Asian Dowitcher. The near threatened Black-tailed Godwit has been recorded in large numbers but not in recent years: counts include 205 in 1993, 450 in 1994, max 15 1995-2000, 268 in 2001, 1 in 2002, 1 in 2003, 0 in 2004, 2 in 2005, 18 in 2006 and 24 in 2007 (Australian Shorebird Count Database). It also supports nationally important and occasionally globally important numbers of Broad-billed Sandpiper (max 205 in 2001); and Curlew Sandpiper: counts include 5199 in 2007, 1608 in 2006, 4332 in 2005, 495 in 2004, 693 in 2003, 1430 in 2002, 11,867 in 2001 and max 4115 in 1993-2000 but not all counts were complete or at optimal times (Australian Shorebird Count Database) and a historical max count of 60,000 (Lane 1987); Little Curlew (max 3261 in 2005, 1280 in 2006 and 1155 in 2004); Sharp-tailed Sandpiper (max thousands on the beach in 1982 and 25,000 in mid-September 1984) (Australian Shorebird Count Database). It has occasionally supported high numbers of terns but the regularity of such numbers is uncertain: max 30,000 White-winged Tern in 2004, with previous highest count of 6000 in 1989 (Minton et al. 2004); max 6046 Roseate Tern in 2004 but only 405 in 2005 (Rogers et al. 2006) and max 1994 Gull-billed Tern in 2003 (Minton et al. 2003c). Non-bird biodiversity: The nationally Vulnerable Flatback Turtle Natator depressus regularly nests at scattered locations along Eighty Mile Beach. The primary dunes of Eighty Mile Beach are stabilised by Spinifex longifolius and Crotalaria cunninghamii. Secondary parallel, calcareous dune ridges and swales commonly feature scattered Dune Wattle Acacia bivenosa. Important grasses include Whiteochloa airoides and the local endemic Triodia epactia, a resinous hummock-forming species. There are two minor mangrove stands within the IBA, each of which occupy about 50 ha around small tidal creeks near Mandora Station. The mangrove stands are dominated by Avicennia marina 4-6 m in height with a few Ceriops tagal. Samphire communities also occur in the vicinity. Many of the 114 species of benthic fauna found in the IBA are present in high densities.

Other site values: Crown Land with four adjoining pastoral leases (Mandora, Anna Plains, Wallal, Pardoo). Permission for access needs to be acquired from stations.

Habitats

Land use: fisheries/aquaculture | not utilised

IUCN Habitat	Coverage %	Habitat detail
Marine Intertidal	100

Threats

Summary of threats to biodiversity at KBA: Minimise disturbance along the roosting and feeding areas used by shorebirds. Ensure that exploration licences and shipping procedures minimise the impact on the beach and inshore waters.

Threat level 1	Threat level 2	Threat level 3	Timing
Biological resource use	Fishing & harvesting aquatic resources	Unintentional effects: large scale (species being assessed is not the target) [harvest]	Ongoing
Energy production & mining	Oil & gas drilling		Only in the future
Human intrusions & disturbance	Recreational activities		Ongoing
Transportation & service corridors	Shipping lanes		Ongoing

Additional information

References: DEWHA (2008) A Directory of Important Wetlands in Australia. Eighty Mile Beach System-WA018. Downloaded from http://www.environment.gov.au/water/publications/environmental/wetlands/database/ accessed November 2008. Lane, B.A. (1987) Shorebirds in Australia. Melbourne: Nelson Publishers. Minton, C., Collins, P., Sitters, H., Hassell, C. and Jessop, R. (2004) NWA wader and tern expedition 24 January to 14 February, 2004. Stilt 45: 54-59. Minton, C., Jessop, R., Collins, P. and Sitters, H. (2003a) Northwest Australia wader and tern expedition from 1 August to 1 November 1998. Stilt 43: 42-46. Minton, C., Jessop, R. and Collins, P. (2003b) Northwest Australia wader and tern expedition from 15 September to 17 November 2001. Stilt 43: 55-67. Minton, C., Jessop, R. and Collins, P. (2003c) A summary of the results of the Northwestern Australia wader and tern expedition from 28 June to 19 July 2003. Stilt 44: 64-72. Minton, C., Jessop, R., Collins, P. and Hassell, C. (2005) NWA 2005 wader and tern expedition, 12 February to 6 March 2005. Stilt 47: 58-64. Piersma, T., Pearson, G.B., Hickey, R. and Lavaleye, M. (eds) (2005) The long mud: benthos and shorebirds of the foreshore of Eighty-Mile Beach, Western Australia. Royal Netherlands Institute for Sea Research, Texel. NIOZ Report 20005/2. Rogers, D.I., Rogers, K.G., Gosbell, K.B. and Hassell, C.J. (2006) Causes of variation in population monitoring surveys: insights from non-breeding counts in north-western Australia 2004-2005. Stilt 50: 176-193. Sitters, K., Minton, C., Collins, P., Etheridge, B., Hassell, C. and O’Connor, F. (2004) Extraordinary numbers of Oriental Pratincoles in NW Australia. Stilt 45: 43-49.