This small 25 hectare wildlife refuge is almost in Nicaraguan waters. It lies 4 kilometers West of Puerto Soley in Salinas Bay on the NW Pacific Coast. The island is in one of the driest regions of the country with often less than 1,500 mm of annual rainfall. It is rugged, oval shaped and lies 4 kilometers from Descartes Point.

It has one of the very few nesting sites in the country for the brown pelican (Pelecanus occedentalis) with a colony of from 500 to 800 individuals.