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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Prince Edward Islands | 3/4 | https://en.wikipedia.org/wiki/Prince_Edward_Islands | reference | science, encyclopedia | 2026-05-05T13:18:39.411145+00:00 | kb-cron |
The islands have been designated an Important Bird Area (IBA) by BirdLife International for their significant seabird breeding populations. At least thirty different species of birds are thought to breed on the islands, and it is estimated the islands support upwards of 5 million breeding seabirds, and 8 million seabirds total. Five species of albatross (of which all are either threatened or endangered) are known to breed on the islands, including the wandering albatross, dark-mantled, light-mantled, Indian yellow-nosed and grey-headed albatross. The islands also host fourteen species of petrel, four species of prion, the Antarctic tern, and the brown skua, among other seabirds. Four penguin species are found: king penguins, Eastern rockhoppers, gentoos and macaroni penguins.
=== Mammals === Three species of seal breed on the islands: the southern elephant seal, the Antarctic fur seal, and the Subantarctic fur seal. The waters surrounding the islands are often frequented by several species of whale, especially orcas, which prey on penguins and seals. Large whales such as southern rights and southern humpbacks, and leopard seals are seen more sporadically, and it remains unclear how large or stable their current local populations are, though it is thought their numbers are significantly down compared to the time of first human contact with the islands. The area saw heavy sealing and whaling operations in the nineteenth century and continued to be subject to mass illegal whaling until the 1970s, with the Soviet Union and Japan allegedly continuing whaling operations into the 1990s. Currently, the greatest ecological threat is the longline fishing of Patagonian toothfish, which endangers a number of seabirds that dive into the water after baited hooks.
=== Terrestrial plants === Like all subantarctic islands, Marion has a small number of native plant species. The isolation of the island and the cold, wet, windy weather conditions filtered out many potential plants from reaching and successfully establishing populations. Only 22 vascular plants were native to the island prior to human arrival. One of them, Ranunculus moseleyi, a species also found in the Kerguelen Islands, is of uncertain status with no records of it being found since 1969 and no specimens in archives to unambiguously prove its presence prior to that date. There are seven species of fern and fern allies include Antarctic hard-fern (Austroblechnum penna-marina), alpine filmy-fern (Hymenophyllum peltatum), Magellanic clubmoss (Lycopodium magellanicum), Notogrammitis crassior, Phlegmariurus saururus, Polystichum marionense, and Elaphoglossum randii. The island has five species of cushion and mat forming flowering plants Azorella selago, Callitriche antarctica, Colobanthus kerguelensis, Crassula moschata, Leptinella plumosa. Other herbaceous plants include Kerguelen cabbage (Pringlea antiscorbutica), Antarctic buttercup (Ranunculus biternatus), Limosella australis, and blinks (Montia fontana). Several grass-like species grow on Marion including the rush Juncus scheuchzerioides, Cook's tussock-grass (Poa cookii), Polypogon magellanicus. The sedge species Carex dikei is endemic to Marion and Prince Edward Island, but was only scientifically described in 2015. Further research is needed to determine if records of Carex austrocompacta on other subantarctic islands might be this species.
=== Invasive species === The wildlife is particularly vulnerable to introduced species and the historical problem has been with cats and mice. House mice arrived to Marion Island with whaling and sealing ships in the 1800s and quickly multiplied, so much so that in 1949, five domestic cats were brought to the research base to deal with them. The cats multiplied quickly, and by 1977 there were approximately 3,400 cats on the island, feeding on burrowing petrels in addition to mice, and taking an estimated 455,000 petrels a year. Some species of petrels soon disappeared from Marion Island, and a cat eradication programme was established. A few cats were intentionally infected with the highly specific feline panleukopenia virus, which reduced the cat population to about 600 by 1982. The remaining cats were killed by nocturnal shooting, and in 1991 only eight cats were trapped in a 12-month period. It is believed that no cats remain on Marion Island today, and with the cats gone, the mouse population has sharply increased to "plague like" levels. In 2003, ornithologists discovered that in the absence of other food sources, the mice were attacking albatross chicks and eating them alive as they sat helplessly on their nests. A similar problem has been observed on Gough Island, where a mouse eradication programme began in 2021. A programme to eradicate invasive rats on South Georgia Island was completed in 2015, and as of 2016 the island appears to be completely rat free. The geography of Marion Island presents certain obstacles not found on either Gough or South Georgia islands, particularly its large size, high elevations and variable weather. An assessment of the island was completed in May 2015, led by noted invasive species ecologist John Parkes, with the general conclusion that an eradication programme is feasible, but will require precise planning. Both Gough Island and the Prince Edward Islands also suffer from invasive procumbent pearlwort (Sagina procumbens), which is transforming the upland ecosystem and is now considered beyond control.
== Legal status ==
Marion Island and Prince Edward Island were claimed for South Africa on 29 December 1947 and 4 January 1948 respectively, by a South African Navy force from HMSAS Transvaal under the command of John Fairbairn. On 1 October 1948 the annexation was made official when Governor-General Gideon Brand van Zyl signed the Prince Edward Islands Act, 1948. In terms of the Act, the islands fall under the jurisdiction of the Cape Town Magistrate's Court, and South African law as applied in the Western Cape applies on them. The islands are also deemed to be situated within the electoral district containing the Port of Cape Town; as of 2016, this is ward 115 of the City of Cape Town.
== Amateur radio ==