Cape Denison (45210)
Antarctica, Antarctica
Site overview
KBA status: confirmed
Year of last assessment: 2015
National site name: Cape Denison
Central coordinates: Latitude: -67.0097, Longitude: 142.6681
System: marine, terrestrial
Elevation (m): 0 to 60
Area of KBA (km2): 1.02012
Protected area coverage (%): 100.00
KBA classification: Regional
Legacy site: Yes
Site details
Site description: Cape Denison is a rocky point at the western entrance to Commonwealth Bay, George V Land. The Cape extends ~1.5 km in width and ~1 km inland, rising to meet the permanent continental icecap at a height of around 40 m. Several valleys, oriented northwest/southeast, contain a number of small glacial lakes, and melt streams can form in summer. Cape Denison served as a base for the Australasian Antarctic Expedition of 1911-14, and a number of historic relics from this era remain. Cape Denison was designated as ASMA No.3 in 2004, although in 2014 this was replaced by an enlargement of ASPA No.162 Mawson's Huts, Cape Denison, to include all of the original ASMA within the boundary of the protected area. The main reason for protection is the site's historic values, although environmental features such as the lakes, flora, mammals and the breeding birds are also listed as of importance (ASPA No.162 Management Plan 2014). The IBA qualifies on the basis of the concentration of seabirds present (in particular Adélie Penguin (Pygoscelis adeliae)) and coincides with the boundary of ASPA No.162. There are no research stations nearby. The closest permanent station is Dumont d'Urville, ~120 km to the west in Terre Adélie.
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: The management plan for ASPA No. 162 (2014) gives 18 800 breeding pairs of Adélie Penguin present at Cape Denison, although the year and source of data are not given. The satellite image analysis by Lynch & LaRue (2014) gave an estimate of ~13 834 breeding pairs (95% CI 8377, 22 671) (February 2011). The penguins nest mainly on the eastern and western coasts of Cape Denison, although are also found in smaller numbers along the northern coast. Map C of the 2014 management plan shows Snow Petrel ( Pagodroma nivea ) and Wilson's Storm-petrel ( Oceanites oceanicus ) breeding on elevated ridges across the cape. A solitary pair of Cape Petrels ( Daption capense ) was reported breeding in 1982 (Woehler & Johnstone 1991), which appears to be shown at the eastern extremity of the cape on a map of Cape Denison (Australian Antarctic Data Centre 2010). At least several pairs of Antarctic Prions ( Pachyptila desolata ) were observed nesting at Cape Denison in 1913 by the Australasian Antarctic Expedition. A pair and a single bird were shot for museum collections, although Antarctic Prions have not been observed at Cape Denison since; this is the only record of Antarctic Prions breeding on the continent apart from the Antarctic Peninsula (Ensor & Bassett 1987). The number of birds breeding at Cape Denison are summarised in Table 157.1. Other non-breeding bird species recorded at Cape Denison include Southern Giant Petrel ( Macronectes giganteus ) and Emperor Penguin ( Aptenodytes forsteri ) (ASPA No. 162 Management Plan 2014). Non-bird biodiversity: Weddell (Leptonychotes weddellii), Southern Elephant (Mirounga leonina) and Leopard (Hydrurga leptonyx) seals are reported to haul out at Cape Denison. Southern Elephant Seals also remain in the area to moult (ASPA No. 162 Management Plan 2014).
Delineation rationale: Coincides with ASPA boundary.
Threats
Summary of threats to biodiversity at KBA: Cape Denison is isolated and difficult of access, although there has been steady interest by tourists over recent years, with visits made in seven out of the 10 seasons from 2004-14. For the years in which visits were made, an average of 197 people per year landed at Commonwealth Bay (IAATO Tourism Statistics, accessed: 18/12/2014). ATS Visitor Site Guidelines have been adopted for the area, which have been updated for consistency with the management plan adopted for ASPA No.162 in 2014, which allows for tourism at the site. Visits are also made to Cape Denison for historical conservation work, scientific research and for management, although because such visits are infrequent and small-scale, these activities are unlikely to pose risks to breeding birds at the site.
Additional information
References: Antarctic Treaty System Visitor Site Guidelines: Mawson's Huts and Cape Denison. URL: http://www.ats.aq/siteguidelines/documents/2014/Mawson's Huts and Cape Denison_e.pdf. Accessed 06/04/2015. Australian Antarctic Data Centre. 2010. Cape Denison, Scale 1: 5000. Edition 3. Catalogue ID 13575. ASPA No. 162 Mawson's Huts, Cape Denison, Commonwealth Bay, George V Land, East Antarctica: Management Plan (2014). 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 Woehler, E.J. & Johnstone, G.W. 1991. Status and conservation of the seabirds of the Australian Antarctic Territory. In Croxall J.P. (ed.) Seabird status and conservation: a supplement. ICBP Technical Publication 11: 279-308.