Biotemas (Sep 2010)
Reproduction of the exotic bullfrog Lithobates catesbeianus (Shaw, 1802) (Anura, Ranidae) in creeks of the Atlantic Rainforest of Minas Gerais, Brazil
Abstract
Reproduction of the exotic bullfrog Lithobates catesbeianus was studied every two months from January 2005 to December 2006, analyzing tadpoles, juveniles, and adult vocalizations at three creeks located in the largest Brazilian center of ornamental fish breeding. Absolute and relative tadpole frequencies were measured bimonthly in three development stages: G1 (no limbs), G2 (hind limbs present), G3 (fore and hind limbs) and I (metamorphs). Results show that, during warmest months, a greater proportion of tadpoles in G1, G2, and G3 phases were found in Santo Antônio and Chato creeks, while G1, G3, and I phases were more common in Gavião creek. Tadpoles in G1 and G2 phases predominated in coldest months at all locations. Male calls and highest average water temperatures and rainfall were recorded at 3 streams during the hottest months. Management measures should be adopted, such as the extermination of larval and adult stages, and initiatives should be taken to prevent new re-introductions, such as: (1) installation of fences around tanks where adults are located, (2) placement of protective screens on the pipes that release waste water from tanks directly into streams, (3) capacity building and educational measures on the problems of biological invasions for staff working on ornamental fish farms.
