Rare species of plants and animals first studied by evolution theorist Charles Darwin are threatened by a rumbling volcano in the Galapagos Islands, a researcher says.

The El Cumbre volcano began spouting lava last week, and a major eruption could kill hundreds of cormorants, hummingbirds and lizards - some found only on the islands 600 miles west of Ecuador - Gonzalo Ceron, head of the islands' Charles Darwin research station, told reporters in Quito on Wednesday.