A new report discusses methods for preserving the biodiversity of islands.

The Bali Starling is one of many endangered species living on islands. Photo: Shutterstock


Islands are often home to great biodiversity as species develop to fill very specific niches there and nowhere else. It was this fact that helped Darwin to develop his theory of evolution, after all. But that potential for diversity also makes those species vulnerable, especially to the predation of mammals like rats or foxes.

Some 40 percent of all species worldwide that face extinction live on islands. Now a new study finds that by carefully exploring how invasive mammals interact with different island ecosystems, we can take serious steps towards preventing many of those extinctions.

The study’s authors believe that without conservation efforts, some 45 percent of island species face extinction, but through the use of targeted invasive animal control and eradication, up to 75 percent of those extinctions could be prevented. While we’ve known for some time that, for example, rats introduced to an island can wreak havoc on the local ecosystem, the new study is geared toward exploring more detailed connections.

On some islands, rats may pose the biggest threat, where on others it may be foxes. There are factors of the ecosystem like how wet or dry the climate is, that can be taken into consideration as well. The point of this work is to figure out what species face the greatest threats, what those threats are, and then move to eliminate them. Because money for conservation can be hard to find, the researchers hope that by better understanding the ways invasive mammals interact with island ecosystems, the easier and more cost effective eliminating them can be.

Once we start to see success stories, it’s possible that we can move on to less threatened populations of animals. Obviously, the end goal of conservation in any form is to keep animals from vanishing, but it’s important to prioritize native animals currently in serious danger so we don’t lose one species while trying to save another.