The Mangrove Finch is just one of the Critically Endangered species that the 2009 Birdfair will highlight. Photo: Michael Dvorak (DWCT)

The population of the Galapagos Mangrove Finch has fallen to about 100 individual, making it one of the world’s most Critically Endangered birds, and the rarest of the 14 closely related finches that Darwin found when he visited the islands.

The mangrove finch has evolved to live in one of the most restricted habitats on the islands as there are only a few strips of mangroves on a few islands. Its remaining population is all found on the island of Isabella.

The main reason for the decline in the mangrove finch is the black rat which became established on Isabella, arriving on pirate vessels perhaps as early as the 16th century. However, it has probably never been numerous as the mangrove habitat is limited.

Conservationists have spent three years investigating its decline, and a new project will now attempt to reverse this. Each year, for three years, 10 young birds will be taken from Playa Tortuga Negra on the western side of Isabella, and they will be moved to Bahia Cartago on the eastern side where there is an additional small area of mangroves.

The project is being led by the Durrell Wildlife Conservation Trust, together with the Charles Darwin Foundation and the Galapagos National Park. Funding is coming from Britain's Department for Environment, Food and Rural Affairs through the Darwin Initiative.  

"The mangrove finch is a quite remarkable piece of evolution," said Glyn Young, the Durrell Trust scientist who is leading the effort. "It's evolved to live in this tiny habitat. It's not as though mangroves have disappeared from the Galapagos – there's just never been much there in the first place. It's a brilliant example of natural selection, filling in this tiny niche."

See: The Independent