Spotlight on the Subantarctic

Humans have exploited the subantarctic islands for centuries, but conservation of these special areas is now a priority, delegates at the first International Forum on the Subantarctic were told.

Organised by Antarctic Tasmania, the forum was held as a satellite to the larger scientific and operational meetings held in Hobart in July. Sir Guy Green, Honorary Antarctic Ambassador for Tasmania, chaired the forum which was attended by 96 delegates from 12 countries.

Over two days, delegates were treated to an overview of the geological structure and formation of the subantarctic islands, their terrestrial biological diversity, and the oceanography, climatology and biodiversity of their surrounding seas. This was followed by a more detailed investigation of their physical environments and ecology. What emerged from this is that the islands, for the most part, are small and young — not over 10 million years old — and have had an unstable existence in recent geological time. Only South Georgia, being an extension of the Andes/Trans-Antarctic mountain spine, has existed into the distant past. All subantarctic islands have low species richness, in sharp contrast with the relative luxuriance of subarctic islands, and many appear to rely on bird guano as their only source of nutrient input.

The history of human use of the islands revealed a sorry tale of butchery of seals from the mid-19th Century, and later bay-whaling and penguin-rendering. With sealers came cats, rats, mice and other unwelcome introductions which are causing great conservation problems today. A few islands have had permanent human inhabitants and nowadays most have seasonal occupation, usually for research purposes. Several are frequently visited by tourists.

Delegates agreed that the subantarctic region is a special part of the world with an identity and characteristics of its own. The existence of common values in and around the islands, and the changing human usage of the islands, may see future forums convened. Long-term monitoring of the environment is critical to future best-practice management, and international collaboration and information exchange will be an important route towards this.

Antarctic Tasmania and Sir Guy Green’s drive and enthusiasm, are to be commended for hosting this worthwhile and valuable meeting.