central america

Feasibility Study for the Cocos Island Mammal Eradication

Cocos Island is situated 500 km off the coast of Costa Rica. It is a World Heritage Site and a 'wetland of international importance' under the Ramsar Convention as well as being a National Park. Cocos Island is home to over 80 species of birds and many other endemic animals and plants. There is also abundant marine life in the waters surrounding the island.

The biodiversity of Cocos Island is threatened by a suite of introduced mammals including pigs, white-tailed deer, cats and two species of rat . These pests destroy native vegetation, prey on native animals and, in the case of pigs, damage the island's coral reefs. This damage occurs when pigs disturb the forest understorey while rooting through the soil looking for food. The lack of understorey vegetation results in large amounts of unstable soil being washed into the sea when it rains, smothering the coral with sediment and reducing water clarity.
 


Cocos Island and assessment team

 

A working group has been set up by the Costa Rican Government to address the threats that these invasive species pose to the biodiversity of Cocos Island. This group involves representatives from IUCN, the Friends of Cocos Island Foundation and the Ministry of Environment and Energy. The aim is to assess the methods and viability of the proposed eradication plan and to develop a plan to manage other invasive species on the island. In 2003, UNESCO through the World Heritgae Fund provided funding for the development of a feasibility study to eradicate invasive alien mammals at Cocos Island.