Carnac Island (Perth) (25097)
Australia, Australasia
Site overview
KBA status: confirmed
Year of last assessment: 2009
National site name: Carnac Island (Perth)
Central coordinates: Latitude: -32.1213, Longitude: 115.6627
System: marine, terrestrial
Elevation (m): 0 to 20
Area of KBA (km2): 0.20528
Protected area coverage (%): 92.71
KBA classification: Global/Regional TBD
Legacy site: Yes
Site details
Site description: Carnac Island is a small limestone island 8 kilometres offshore, between Garden and Rottnest Islands, south-west of Perth. The island is comprised of calcareous sandstone and lacks permanent fresh water. The coast is mostly cliffs 10-15 m high, with one large beach on the eastern shore and two smaller beaches in the west. The IBA also includes the small offshore rocks and reefs which are used by some seabirds. The average annual rainfall for nearby Rottnest island was 668 mm between 1950–95. Carnac is a popular location for fishing, as the eastern side of the island provides sheltered anchorage for boats. The island receives an estimated 12,000 visitors annually, mostly on commercial tours but also on private boats.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance because it meets one or more previously established criteria and thresholds for identifying sites of biodiversity importance (including Important Bird and Biodiversity Areas, Alliance for Zero Extinction sites, and Key Biodiversity Areas)
Additional biodiversity: The island also is an important nesting habitat for several species of seabirds such as Little Penguin (50-80 pairs in 1980; most northerly breeding site in WA), Wedge-tailed Shearwater (140-200 pairs in 1980), Pied Cormorant (450-550 pairs in 1980 and 1993), Pied Oystercatcher (1-2 pairs in 1980), Caspian Tern (a handful of pairs in 1980), Bridled Tern (50-100 pairs in 1980), Crested Tern (about 200 pairs in 1980) and Silver Gull (3000 pairs in 1977/8 and 3000-4000 in 1980) (Wooller and Dunlop 1979; Dunlop and Storr 1981; Abbott et al. 2000). Non-bird biodiversity: Australian Sea-lions use Carnac Island as a haul-out area during the non-breeding season. A large population of tiger snakes inhabits the island.
Other site values: Western Australian State Government with management the responsibility of WA DEC. Day visits are allowed with licensed tour operators.
Habitats
Land use: nature conservation and research (100%)
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Marine Coastal/Supratidal | 29 | |
| Shrubland | 29 | |
| Marine Intertidal | 14 | |
| Introduced Vegetation | 29 |
Threats
Summary of threats to biodiversity at KBA: Visitor access regulations, signage and fencing should be adjusted seasonally to protect the variable location of Fairy Tern breeding colonies. The breeding success of Fairy Terns should be investigated to determine the impacts of various threats.
| Threat level 1 | Threat level 2 | Threat level 3 | Timing |
|---|---|---|---|
| Invasive & other problematic species, genes & diseases | Problematic native species/diseases | Named species | Ongoing |
| Human intrusions & disturbance | Recreational activities | Ongoing |
Additional information
References: Abbott, I., Marchant, N. and Cranfield, R. (2000) Long-term change in the floristic composition and vegetation structure of Carnac Island, Western Australia. Journal of Biogeography 27: 333-346. Conservation Commission of Western Australia (2003) Carnac Island Nature Reserve management plan. Perth: Dept. of Conservation and Land Management. Dunlop, J.N. and Storr, G.M. (1981) Seabird islands No.111. Carnac Island, Western Australia. Corella 5: 71-74. Wooller, R.D. and Dunlop, J.N. (1979) Multiple laying by the Silver Gull Larus novaehollandiae Stephens, at Carnac Island, Western Australia. Australian Wildlife Research 6: 325-335.
Contributors: Sue Mather provided much of the underlying data.