Relative abundance and habitat use by the frogs Pristimantis shrevei (Strabomantidae) and Eleutherodactylus johnstonei (Eleutherodactylidae) on St. Vincent

Abstract

St. Vincent, one of the Windward Islands of the Lesser Antilles, is home to four amphibian species, only one of which (Pristimantis shrevei) is endemic. Pristimantis shrevei (Strabomantidae) is restricted to the highlands, whereas Eleutherodactylus johnstonei (Eleutherodactylidae), an introduced species, has become widely distributed throughout the island. We established and surveyed 26 transects at three sites and recorded the numbers of P. shrevei and E. johnstonei, encounter rates, and all perch types and heights. In general, P. shrevei was more abundant in less disturbed sites at higher elevations and absent from low elevations, whereas E. johnstonei was more abundant at lower elevations and in more severely disturbed or altered sites. Both species used elevated perches more frequently than the ground and were not selective regarding microhabitat types.