Environmental Conservation at the Sub-Antarctic Prince Edward Islands: A Review and Recommendations

Abstract

With respect to environmental conservation at* the Prince Edward Islands, South Africa has not lagged behind other nations owning sub-Antarctic islands. Indeed, with respect to some aspects, it can claim to be in the forefront. The most serious environmental problems at the Prince Edward Islands have to do with the need for control or eradication of certain established alien species of both plants and animals, the prevention of the introduction of additional aliens, and the carrying out of environmental impact assessments prior to new developments or expansions of existing facilities and programmes. However, where South Africa has lagged behind is in the enunciation of a policy on, and the proclamation of legislation giving, formal status to environmental conservation at, and the implementation of a formal and effective management plan for, the Prince Edward Islands.It is hoped that these shortcomings will be redressed in the near future. But if, for example, an aircraft landing strip were ever to be built on Marion Island, then the need for the proclamation of legislation and the implementation of a management plan would become even greater than at present. Prince Edward Island is so exceptionally special as an undisturbed sub-Antarctic island that it must never be subjected to any such development.

Counts of Surface-nesting Seabirds Breeding at Prince Edward Island, Summer 2001/02

“…The subantarctic Prince Edward Islands are globally important breeding sites for seabirds (Williams et al 1979, Cooper andBrown 1990), including eight Threatened and five Near Threatened species (BirdLife International 2000). Accordingly, the islands are recognized as an Important Bird Area (Barnes et al 2001) and are afforded the highest level of conservation protection under South African law, being designated as Special Nature Reserves (Prince Edward Islands Management Plan Working Group 1996).…”

Decrease in Numbers of the Eastern Rockhopper PenguinEudyptes Chrysocome Filholiat Marion Island, 1994/95–2002/03

“…In such a situation, van Zinderen Bakker's estimate for 1965/66 is equivalent to about 270 000 breeding pairs. In the 1970s, there were thought to be 35 000 pairs of rockhopper penguins at Prince Edward Island (Cooper and Brown 1990). Subtracting this value from van Zinderen Bakker's estimate leaves a population of 235 000 pairs at Marion Island in 1965/66.…”

“…Laying takes place in late November and early December, and chicks hatch in late December and early January and fledge by mid March (Cooper and Brown 1990). The normal clutch of rockhopper penguins is two eggs (Williams 1980a).…”

“…From 1994/95 to 2001/02, 30 -45 stomach samples were collected each season between 6 January and 9 March, during the chick-rearing period (Cooper and Brown 1990). Birds were caught when they came ashore and their stomachs emptied using a stomachflushing technique modified (water was poured down a tube rather than pumped into the stomach) from that described by Wilson (1984).…”

“…Assuming that 70% of nests hatched chicks (Cooper et al 1997), the total breeding population for 2001/02 was considered to be about 45 000 pairs (Ryan et al 2003). The population in the 1980s was thought to be about 35 000 pairs (Cooper and Brown 1990). The higher estimate for 2001/02 may have resulted from greater coverage in that year and from bias introduced from counting loafing birds as breeders in colonies that were observed at a distance.…”