Balleny Islands
The remote Balleny Islands are a trio of uninhabited
islands lying at the northwestern fringes of the Ross Sea, astride the Antarctic Circle. They are located some 300 km off
the Oates Coast and Pennell Coast regions of Antarctica's Victoria Land. The New Zealand sub-Antarctic islands of Macquarie
Island and Campbell Island lie 1,290 km and 1,565 km to the north and northeast, respectively.
The islands form part of the Ross Dependency — Antarctic territorial claims of New Zealand.
The Balleny Islands (785 km²) form a short, northwest to southeast orientated, 190 km long chain of islands. There are three main islands: Young Island (225 km²), Buckle Island (123 km²) and Sturge Island (437 km²). Offshore from the main islands are numerous smaller islets, sea stacks and emergent rocks. The largest off the minor islets include Sabrina Island (0.2 km²) off Buckle Island, Row Island (1.7 km²) and Borradaile Island (3.5 km²), both located off Young Island. Smaller islets and stacks include the Seal Rocks and Pillar off northeastern Young Island, Scott Cone, The Monolith and Chinstrap Islet off southern Buckle Island and Eliza Cone off the western coast of Buckle Island.
The islands are often locked in the Antarctic pack ice (see ice-bound image); when the ice breaks up during the brief Austral summer, the islands are surrounded by ice flowing from the interior of the bay-like Ross Sea.
The larger islands are all similar in character: narrow and elongate in shape with typical dimensions of 23-38 km in length and 6-10 km in width. Rising sharply from the sea floor, the islands rise steeply from the sea via rocky cliffs to elevations of up to 1,524 m above sea level (Brown Peak on Sturge Island). The Balleny Islands have very few areas of low coastal terrain — beaches of gravel occur on the smaller Row, Sabrina and Borradaile islands. The interiors of all three islands lie buried beneath thick ice caps, that in places often descend directly to the sea.
The few beaches of the Balleny Islands support breeding colonies of Adelie penguins (Pygoscelis adeliae) at Cape Cornish on Buckle Island and on Sabrina Island; small numbers of Chinstrap penguins (Pygoscelis antarcticus) nest on the nearby Chinstrap Island as well as on Buckle Island. The high cliffs of the main islands and the isolated rocky stacks offshore support colonies of seabirds such as Antarctic Petrel (Thalassoica antarctica), Cape Petrel (Daption capense), Snow Petrel (Pagodroma nivear), Southern Fulmar (Fulmarus glacialoides), and Wilson's Storm Petrel (Oceanites oceanicus).
Marine mammals also use the Balleny's few beaches as haul-out grounds and the surrounding waters for hunting, though they do not breed on the islands. Species commonly observed include, Crabeater Seal (Lobodon carcinophagus), Southern Elephant Seal (Mirounga leonina) and Weddell Seal (Leptonychotes weddellii).
