Current view: Text account
Site description (2008 baseline):
Site location and context
The Sir Joseph Banks Islands IBA consists of all 20 islands in the Sir Joseph Banks Group at the neck of the Spencer Gulf in South Australia. It includes the 18 islands that make up Sir Joseph Banks Group Conservation Park, which together cover a total land area of approximately 1242 ha and a total area of 47,528 ha, and also Dangerous Reef to the south. The islands are low-lying, reaching a maximum height of 50 m on Spilsby Island, and are composed mainly of limestone on a granite base topped with calcrete or sandy soil. Many of the islands in the group are covered by low shrubland dominated by Nitre Bush and/or African Boxthorn. Some islands, especially those recovering from disturbance, support tall shrubland dominated by Coastal Boobialla or Coastal Daisy-bush. Most islands also have some areas of sandy loam with shrubland dominated by Marsh Saltbush, and some of the larger islands retain patches of woodland and open scrub. Introduced grasses and Burr Medick are prevalent on islands formerly used for grazing. Spilsby Island, which is excluded from the conservation park but included in the IBA, continues to be grazed by some sheep, and also has a small number of holiday houses. The Cape Barren Goose was recorded breeding on 14 islands during a survey in 1996, including a total of 328 adults on Reevesby Island. Introduced cats, House Mice, chinchilla rabbits and goannas are present on many of the islands in the IBA.
The Eastern Reef Egret has been recorded in the group and is listed as a threatened species in South Australia under the National Parks and Wildlife Act 1972. The Little Penguin bred and was present in good to large numbers on several islands in the IBA in 1979-80, with at least several hundred pairs on Reevesby Island in 1979-80 and approximately 50 pairs on Lipson Island in 1990-91 (Copley 1996). The Silver Gull was abundant on Blythe, Duffield and Sibsey Islands and common on Stickney Island in 1979-80, with a large breeding colony on Marum Island in 1979-80 and about 60 adults plus chicks on Dangerous Reef in 1982 (Copley 1996). The Crested Tern breeds in colonies on Kirkby (380 nestlings banded 1966-67), Lipson (790 nestlings banded 1986-87) and Winceby (a 'large' breeding colony 1979-80) Islands (Copley 1996).
Non-bird biodiversity: The Australian Sea-lion breeds on islands in the Sir Joseph Banks Group and the Greater Stick-nest Rat was reintroduced to Reevesby Island in 1990/91. The Australian Sea-lion and Greater Stick-nest Rat are listed as nationally threatened species under the Environment Protection and Biodiversity Conservation Act 1999. The Tiger Snake is common on several of the islands within the IBA.
Pressure/threats to key biodiversity
Access to the islands is difficult to regulate. Consequently, human intrusions may cause difficulties for some species during their breeding seasons.
Conservation responses/actions for key biodiversity
Studies are being conducted on the Australian Sea-lion, Greater Stick-nest Rat and Tiger Snake populations in the IBA.
The IBA overlaps with Sir Joseph Banks Group Conservation Park.
Eighteen islands are owned by the state and managed by the Department for Environment and Heritage; two islands are private land.
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Sir Joseph Banks Islands (Australia). Downloaded from
https://datazone.birdlife.org/site/factsheet/sir-joseph-banks-islands-iba-australia on 22/11/2024.
