NATURAL HISTORY

PUERTO RICO ROCK FROG } Eleutherodactylus cooki
FAMILY: Leptodactylidae

DESCRIPTION: Female guajóns are slightly larger than males, reaching approximately 3.5 inches in length . Guajóns are solid brown with whitish underparts and large, white-rimmed eyes, giving them a phantom-like appearance. Breeding males and some females may have a yellow throat and abdomen. The species is characterized by large truncate discs under the frogs' feet and a peculiar, melodious, low voice completely different from any other coquí species in Puerto Rico.

HABITAT: The guajón primarily occupies caves and rock grottos in the spaces between large granite boulders, as well as some rivers with rocky shores.

RANGE: The species inhabits the Pandura range in southeastern Puerto Rico west to Patillas/San Lorenzo.

MIGRATION: The guajón does not migrate.

BREEDING: Eggs are laid on the humid faces of boulders within the grottos. The males guard the clutches, which average 17 eggs. Up to four clutches from different females are guarded together.

LIFE CYCLE: Breeding occurs from March to November, and eggs hatch within a month.

FEEDING: The guajón's feeding habits are unknown.

THREATS: Threats include deforestation, construction and industrial development, runoff from the use of pesticides and fertilizers in agriculture, the use of caves as garbage dumps, and fire.

POPULATION TREND: The population trend is unknown, but the species is extremely restricted in geographical distribution and occurs only on privately owned lands. All individual frogs are in fewer than five locations.

Photo by J.P. Zegarra, USFWS