island off the coast of southern Ecuador, at the head of the Gulf of Guayaquil, opposite the mouth of the Guayas River. It is flanked by two channels, the Jambelí Channel on the east and the Morro Channel on the west, and has an area of approximately 330 square miles (855 square km).

In the 16th century the island served as a stopping point for Spanish conquistadors (including Francisco Pizarro) on their way south from Panama; it was originally inhabited by the aboriginal Tumbez Indians, whom not even the Inca had conquered. The present population is concentrated around the village of Puná at the island's northeastern tip. Punta Salinas is a fishing and hunting resort on the southwestern cape.