Hotspot of adult cuban treefrog and cane toad multi organ abnormality in suburban South west Florida

Abstract

This study represents a continuation of the Florida hotspot of tadpole abnormality found in the Southwest Florida suburban roadside drainage ditches in 2012 to determine if the adult frogs and toads frequenting the study sites were anatomically abnormal. The gross examination of all organs included 397 adult anurans and 40 metamorphs representing five anuran species: Osteopilus septentrionalis (N=364), Rhinella marina (N=60), Lithobates sphenocephala (N=7), Anaxyrus terrestris (N=5) and Anaxyrus americanus (N=1). The gonads, liver, kidney and intestines were abnormal at a frequency of 87.4%. The few normal anurans (12.6%) were females and young male adults. We found a significant difference in organ abnormality type and frequency between sexes. Almost all f rog and toad males had testicular abnormality (92%) with only 6% with normal testes, whereas the female gonad abnormality was lower, at 41.6%. Hermaphroditism was found in both sexes at a frequency of 26.2%. The toads had a significantly higher frequency of hermaphroditism than the frogs. The toad hermaphroditism frequency was found to be 40%, whereas the frog hermaphroditism 23.3%. A hermaphrodite Cane toad male with a female phenotype coexisted with the normal male phenotype hermaphrodite. The fertility of 27 in situ pairs was assessed. The fertile testicular abnormal male and hermaphrodite pairs produced offspring with abnormal larval morphology. This information adds new evidence of the effect of chemicals on wild populations and the effect on non-target species which has always been underestimated.