Reproduction and growth of the Southern Leopard Frog, <em>Lithobates sphenocephalus</em> (Cope, 1886), in Virginia: implications for seasonal shifts in response to global climate change

Abstract

An examination of 750 museum specimens of the Southern Leopard Frog (Lithobates sphenocephalus) collected during 1938-1989 from eastern Virginia (USA) provided comparative life-history data from the northeastern portion of this species geographic range. Individuals were collected in all months except December. Testis size was largest and incidence of gravid females was highest during fall and spring. In both sexes, fat storage was lowest during late-winter-spring, which is indicative of increased activity and commencement of breeding. Incidence of food in stomachs was lowest in late winter and relatively high thereafter, especially in males. Geographic trends in five life-history traits were corroborated for the Southern Leopard Frog in this study, including breeding season, egg size, mean adult body size, sexual size dimorphism, and larval metamorphosis season. In response to hotter summers and milder winters, as predicted to occur with climate change, the reproductive characteristics for this species in Virginia will likely shift to resemble contemporary reproductive patterns of southern populations