VERTEBRATE PALEONTOLOGY OF ISLA DE MONA, PUERTO RICO

Vertebrate fossil materials were collected from over a dozen cave localities on Isla de Mona, Puerto Rico. Guano deposits at these localities were excavated and sifted to recover bone materials. The predominant vertebrate fossils recovered at every sifting site were Audubon’s shearwater (Puffinus lherminieri) bones. Fragmentary undifferentiated lizard bones were also found sporadically in the sifted material. Fossil skeletal bones and fresh bones from other bird species were found on the surface of the cave floors at several localities. Extensive fossil guano deposits on the island are interpreted to be of mixed origin with deposits near entrances primarily derived from bird guano, and deposits from the darker interiors of the caves derived from bat guano. Isla de Mona is a small, isolated island located in the Mona Passage, 68 km west of Puerto Rico and 60 km east of Hispaniola. There are a limited number of native, non-flying, vertebrate species extant on Isla de Mona. These include nine species of terrestrial reptiles (six lizards and three snakes), one species of amphibian (coqui tree frog), and two species of native mammals, both bats (Wiewandt 1973). Five species o