Included here is a series of subantarctic islands comprising the Kerguelen Islands, Marion Island, Prince Edward Islands, Crozet Islands, Heard Islands, McDonald Island, Saint Paul Island and Amsterdam Island.

Kerguelenian Poa cookii Grassland

Characterized by the endemic tussock grass Poa cookii (Poaceae), this vegetation is one of the southern hemisphere’s so-called ornithocoprophilus or bird guano loving communities found around seabird colonies and, in this case, penguin rookeries. It has a similar structure and ecology to the Poa foliosa and Poa flabellata communities found on other sub Antarctic islands like Macquarie, South Georga, Gough and Tristan da Cunha. There are no large herbivores so grazing is not an important factor, but trampling, especially by herds of elephant seals, can have a major impact. Consequently there are areas, often between tussocks of Poa cookii, where the vegetation has a pioneer character consisting largely of therophytes, particularly Callitriche antarctica and Montia fontana. Where there is less guano and trampling, other species may be found, notable mosses such as Brachythecium rutabulum, Leptodontium proliferum, Mielichoferia campylocarpa and liverworts like Marchantia berteroana and the endemic Lophozia cylindriformis. Other endemic liverworts associated with these grasslands are Andrewsianthus carinatus, A. lancistipus, Cephalozia randii and Metzgeria grollei.

References

Bergstrom, D. M. & Chown, S. L. 1999. Life at the front: history, ecology and change on southern ocean islands. Tree, 14: 472-477.

Chapuis, J. L., Frenot, Y. & Lebouvier, M. 2004. Recovery of native plant communities after eradication of rabbits from the sub Antarctic Kerguelen Islands, and the influence of climate change. Biological Conservation, 117: 167-179.

Frenot, Y., Gloaguen, J. C., Cannavacciuolo, M. & Bellido, A. 1998. Primary succession on the glacier forelands in the sub Antarctic Kerguelen Islands. Journal of Vegetation Science, 9: 75-84.

Gremmen, N. J. M. 1982. The vegetation of the sub Antarctic islands Marion and Prince Edward. Dr W. Junk Publishers.

Grolle, R. 2002. The Hepaticae and Anthocerotae of the sub Antarctic and temperate islands in the eastern Southern Hemisphere - an annotated list. Journal of Bryology, 24: 57-80.

Kidder, J. H. 1876. Contributions to the natural history of Kerguelen Island made in connection with the United States transit-of-Venus Expedition, 1874-75. Bulletin of United States National Museum, No. 3.

Scott, J. J. 1990. Changes in the vegetation on Heard Island 1947-1987. In: Antarctic Ecosystems. Ecological Change and Conservation. Eds. K. R. Kerry and G. Hempel. Springer-Verlag.

Smith, H. G. et al. 1974. A biological survey of St Paul’s Rocks in the equatorial Atlantic Ocean. Biological Journal of the Linnaean Society, 6: 89-96.

Wace, N. M. 1960. The botany of southern oceanic islands. The Royal Society Expedition to Southern Chile. Proceedings of the Royal Society, 152: 475-490.

Wace, N. M. 1965. Vascular Plants. In: Biogeography and Ecology in Antarctica. Eds. Mieghem, J. Van, Oye, P. Van and Schell, J. Dr Junk Publishers. The Hague.