Study reveals ocean island’s rich biodiversity

A study around the sub-Antarctic island of South Georgia by a team from the British Antarctic Survey (BAS) has revealed a biologically rich marine region greater than even many tropical sites. Funded by the British Government’s Darwin Initiative and the South Georgia Heritage Trust, the team examined over 130 years of polar records, highlighting
about 1500 species from around South Georgia and its surrounding islands.

Lead author Oliver Hogg from BAS said: “The biodiversity of South Georgia exceeds that of its nearest rivals such as the Galapagos and Equador in terms of the number of species inhabiting its shores. During the breeding season it hosts the densest mass of marine mammals on Earth.”

Specimens were collected from scientific cruises, fisheries vessels and by scuba divers from the seas around South Georgia, famous for great polar explorer Sir Ernest Shackleton’s expedition. Species identified include sea urchins, freeswimming worms, fish, sea spiders and crustaceans. Most are rare and many occur nowhere else on Earth. The
near-surface waters around South Georgia are some of the fastest warming on Earth so this study provides a
framework to identify ecologically sensitive areas and species, identify conservation priorities and monitor future
changes.

Oliver Hogg continued: “This is the first time anybody has mapped out the biodiversity of a small polar archipelago in the Southern Ocean. If we are to understand how these animals will respond to future change, a starting point like this is really important.”