WOLF ISLAND

Wolf is inhabited only by sea birds and is rarely visited by tourists other than master divers. There is no terrestrial visitor site on the island. The main attraction of this tiny island is the dive site known as El Derrumbe. It is well-known among divers for its diverse and abundant marine wildlife. Because of the cold currents, the Great Spotted Whale Shark, various species of whales, and Hammerhead, White-tipped, and Galápagos Sharks are often seen. While many seabirds frequent the cliffs of the island, the most famous resident is the vampire finch.

The same species as the Sharp-beaked Ground Finch (Geospiza difficilis), on Wolf Island these birds have developed a curious and perhaps a bit repugnant behavior – drinking the blood of the Nazca and Red-footed Boobies and other birds that nest on the island. The climate on Wolf is extremely dry most of the year and the seeds that are produced in the brief periods of rain are quickly eaten by the finches. To survive the long dry spells, the finches developed this extraordinary behavior. They peck the skin of the booby at the base of their feathers with their very sharp beaks until they draw blood. Other finches line up behind the booby and as soon as one leaves another takes its place.

It is theorized that this behavior evolved from the pecking behavior used to eat parasites that live within the plumage. Curiously their feeding does not appear to harm the boobies. The vampire finch also feeds on booby eggs, as well as the lubricating fluids released by the boobies when they lay the eggs. However, some finches are not strong enough to crack the eggs, so they roll them until they fall and crack.