Climate of Our Future

ScienceDaily (May 11, 2009) — Rare and unique ecological communities will be lost if oceanic islands aren’t adequately considered in a global conservation plan, a new study has found. Although islands tend to harbor fewer species than continental lands of similar size, plants and animals found on islands often live only there, making protection of their isolated habitats our sole chance to preserve them.

Many conservation strategies focus on regions with the greatest biodiversity, measured by counting the number of different plants and animals. “Normally you want to focus on the most diverse places to protect a maximum number of species,” said Holger Kreft, a post-doctoral fellow at the University of California, San Diego and one of the two main authors of the study, “but you also want to focus on unique species which occur nowhere else.”

To capture that uniqueness, Kreft and colleagues at the University of Bonn, UC San Diego and the University of Applied Sciences Eberswalde used a measure of biodiversity that weights rare species more than widespread ones. They carved the terrestrial realm into 90 biogeographic regions, calculated biodiversity for each, then compared island and continental ecosystems. By this measure, island populations of plants and vertebrate animals are eight to nine times as rich. Keep Reading