Avian Island
| Avian Island | ||
|---|---|---|
| Waters | Marguerite Bay | |
| Archipelago | Adelaide and Biscoe Islands | |
| Geographical location | 67 ° 46 ′ 21 ″ S , 68 ° 53 ′ 28 ″ W | |
|
||
| length | 1.45 km | |
| width | 800 m | |
| surface | 49 hectares | |
| Highest elevation | 39 m | |
Avian Island (meaning bird island ) is a small island off the Adelaide Island in the west of Marguerite Bay on the west side of the Antarctic Peninsula .
The only 49 hectare island is 1.45 km long and up to 800 m wide. It reaches its greatest height in the south with 38.7 m. It is roughly triangular in shape, but - especially in the northwest - has a strongly indented, rocky coastline with numerous offshore rocky islands. In summer the island is mostly ice-free. During this time there are short-lived freshwater lakes that can be up to one hectare in size and up to 40 cm deep.
A polynya regularly forms near Avian Island . Strong tidal currents and occasional katabatic winds from Adelaide Island keep the surrounding waters ice-free for much of the year.
Avian Island has been under the protection of the Antarctic Treaty since 1991 and ASPA-117 as a specially protected area since 2002 . The main reason for protection is their high density of seabirds , which are represented here as breeding birds by seven species in very specific habitats . In 2013, 300 pairs of blue-eyed shags nested on the well-drained northern slopes. On the other hand, rugged rocky areas provide a suitable habitat for hundreds of breeding pairs of the red-legged petrel . Avian Island has one of the largest populations of the giant petrel in the southern part of the Antarctic Peninsula. In 2013, 470 breeding pairs were counted. The colony of Adelie penguins , which covers the entire northern half of the island and the central area of the east coast, has long been considered the largest on the Antarctic Peninsula. Recent findings contradict this, but in 2013 a substantial population of 77,500 breeding pairs was identified. Attracted by the colony, the Antarctic and Sub- Antarctic skua and the Dominican gull breed on Avian Island .
The vegetation on the island is very sparse. So far, 9 types of moss and 11 types of lichen have been identified. The moor sickle moss Warnstorfia fontinaliopsis is here on the southern edge of its range. Moss mats with an area of 100 m² occur on the banks of a small freshwater pond in the east of the island. The green alga Prasiola crispa is widespread in damp areas .
Avian Island was discovered by the Fifth French Antarctic Expedition (1908-1910) led by Jean-Baptiste Charcot . The Falkland Islands Dependencies Survey visited the island in 1948 and named it after the large number of different bird species.
Web links
- Avian Island in the Geographic Names Information System of the United States Geological Survey (English)
- Avian Island on geographic.org (English)
Individual evidence
- ↑ a b Management Plan for Antarctic Specially Protected Area No. 117: Avian Island, Marguerite Bay, Antarctic Peninsula (PDF; 4.59 MB), Secretariat of the Antarctic Treaty, 2013 (English)