Shirley Island / Beall Island (45201)
Antarctica, Antarctica
Site overview
KBA status: confirmed
Year of last assessment: 2015
National site name: Shirley Island / Beall Island
Central coordinates: Latitude: -66.2961, Longitude: 110.4806
System: marine, terrestrial
Elevation (m): 0 to 50
Area of KBA (km2): 4.14098
KBA classification: Regional
Legacy site: Yes
Site details
Site description: Shirley Island and Beall Island are part of the Windmill Islands group, Budd Coast, Wilkes Land. Shirley Island lies ~200 m west and Beall Island ~ 600 m southwest of Bailey Peninsula. Shirley Island is ~1.5 km long and ~0.5 km wide with a maximum elevation of 37 m, while Beall Island is ~2 km long and up to 1.5 km wide with a maximum elevation of 48 m. Both islands are mostly ice free with rocky, undulating terrain. Several small lakes are present on Beall Island, the largest of which lies at the north of the island and is saline (Hodgson et al. 2006). The IBA qualifies on the basis of the Adélie Penguin (Pygoscelis adeliae) colony present and comprises Shirley Island, Beall Island and the intervening marine area. The nearest permanent station is Casey (AUS), ~1 km to the east on Bailey Peninsula.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that was identified using previously established criteria and thresholds for the identification of Important Bird and Biodiversity Areas (IBAs) and for which available data indicate that it does not meet global KBA criteria and thresholds set out in the Global Standard.
Additional biodiversity: Woehler et al. (1991) counted 7637 and 5225 breeding pairs of Adélie Penguin on Shirley Island and Beall Island respectively in 1989/90 (12 862 in total). Murray & Luders (1990) reported an average of around 7500 pairs breeding on Shirley Island in the 1970s. This compares with approximately 13 658 breeding pairs (95% CI 8163, 22 603) of Adélie Penguin present on Shirley Island and Beall Island as estimated from January 2011 satellite imagery (Lynch & LaRue 2014). On Shirley Island breeding is concentrated in the southwest, with smaller groups occupying the northeast, while on Beall Island breeding is mainly on elevated ground in the south. Snow Petrels (Pagodroma nivea) are widely distributed on Beall Island (Australian Antarctic Data Centre 2012), with ~452 breeding pairs counted in 2002/03 (Olivier, Lee & Woehler 2004). Snow Petrels also breed on the northeastern coast of Shirley Island, with ~61 breeding pairs counted in 2002/03 (Olivier, Lee & Woehler 2004). Wilson's Storm-petrel (Oceanites oceanicus) and South Polar Skua (Catharacta maccormicki) are confirmed breeding on Beall Island (Australian Antarctic Data Centre 2012), although numbers are not known. Non-bird biodiversity: Weddell (Leptonychotes weddellii), Leopard (Hydrurga leptonyx) and Southern Elephant (Mirounga leonina) seals have been reported in the area (Woehler et al. 1991).
Delineation rationale: Shortest perimeter around island groups and/or ice-free areas ≤ 5 km2, including marine areas as appropriate.
Threats
Summary of threats to biodiversity at KBA: Shirley Island and Beall Island lie in close proximity to Casey Station, and as such station operations have the potential to affect birdlife on these islands. In particular, both fixed wing and helicopter aircraft regularly operate out of Casey Station during the summer breeding season, and local flight paths pass within several km of the islands. Aircraft access is tightly regulated taking into account the number and location of breeding birds, although potentially adverse conditions may force aircraft to pass near or over breeding colonies on these islands. Shirley Island lies within the limits of recreational access for station personnel (Australian Antarctic Data Centre 2014). Travel to Shirley Island for recreational and other purposes is allowed by permission of the station leader and in accordance with Australian Antarctic Division (AAD) operational procedures, and visitors are required to follow AAD wildlife viewing guidelines. Beall Island lies outside of Casey recreational limits, and visits to this island are likely therefore to be more limited and related to scientific or management purposes only with the permission of the station leader.
Additional information
References: Australian Antarctic Data Centre. 2012. Windmill Islands Map 2 of 5, Scale 1: 50 000. Edition 6. Catalogue ID 14111. Australian Antarctic Data Centre. 2014. Casey: recreational limits, Scale 1: 15 500. Edition 5. Catalogue ID 14295. Bricher, P.K., Lucieer, A. & Woehler, E.J. 2008. Population trends of Adélie Penguin (Pygoscelis adeliae) breeding colonies: a spatial analysis of the effects of snow accumulation and human activities. Polar Biology 31(11): 1397-407. doi:10.1007/s00300-008-0479-z Hodgson, D. A., Roberts, D., McMinn, A., Verleyen, E., Terry, B., Corbett, C.& Vyverman, W. 2006. Recent rapid salinity rise in three East Antarctic lakes. Journal of Paleolimnology 36(4): 385-406. doi:10.1007/s10933-006-9010-0 Lynch, H.J. & LaRue, M.A. 2014. First global census of the Adélie Penguin. The Auk 131(4): 457-66. doi:10.1642/AUK-14-31.1 Murray, M.D. & Luders, D.J. 1990. Faunistic studies at the Windmill Islands, Wilkes Land, East Antarctica, 1959-80. ANARE Research Notes 73 (IV): 1-45. Olivier, F., Lee, A.V. & Woehler, E.J. 2004. Distribution and abundance of Snow Petrels Pagodroma nivea in the Windmill Islands, East Antarctica. Polar Biology 27: 257-65. doi:10.1007/s00300-004-0595-3 Woehler, E.J., Slip, D.J., Robertson, L.M., Fullagar, P.J. & Burton, H.R. 1991. The distribution, abundance and status of Adélie Penguins Pygoscelis adeliae at the Windmill Islands, Wilkes Land, Antarctica. Marine Ornithology 19(1): 1-18.