LAFIANDRA, E.M.*; BABBITT, K.J.; SOWER, S.A.; Univ. of New Hampshire, Durham; Univ. of New Hampshire, Durham; Univ. of New Hampshire, Durham: Morphological and reproductive abnormalities in wild caught Rana clamitans, Rana pipiens, and Rana utricularia metamorphs

The prevalence of malformed amphibians and the association of high incidences of malformation with the presence of environmental contaminants have raised questions about the effects of contaminants such as PCBs, DDT, and pesticides on the development of larval amphibians. Recent research has shown that pesticides may have endocrine disrupting effects, suggesting that many of the observed reproductive and developmental abnormalities may be due at least in part to the alteration of steroidogenesis. To determine if amphibians in the wild are experiencing reproductive abnormalities that may be due to the endocrine disrupting effects of environmental contaminants, we examined the external and reproductive morphology of metamorphs collected at National Wildlife Refuges. Sites on refuges in Maryland, Minnesota, New Hampshire, and Vermont were selected based on their relatively high incidences of amphibian malformations and/or the presence of potential endocrine disrupting chemicals. External morphological malformation rates ranged from 4% to 14% and included brachydactyly, microagnathia, polyphalangy, ectromelia of femur and tibiafula, amelia of both hind limbs, and abnormal iris formation. Gross reproductive abnormalities included the unilateral absence of gonads in two animals, suggesting that other less obvious abnormalities may also be present. These data document reproductive abnormalities in amphibians exposed to environmental contaminants and may lend support to the theory that these chemicals have endocrine disrupting effects. Supported by USF&WS to KB.