Spatio-temporal dynamics of pond use and recruitment in Florida gopher frogs (Rana capito aesopus)
This study examines spatio-temporal dynamics of Florida gopher frog (Rang capito aesopus) breeding and juvenile recruitment. Ponds were situated within a hardwood-invaded or a savanna-like longleaf pine-wiregrass upland matrix. Movement (N = 1444) was monitored using intermittent drift fences with pitfall and funnel traps at eight isolated, ephemeral ponds February 1994 to January 1999. Adult pond use was low but relatively constant among years and did not differ between habitat matrices. Juvenile recruitment was significantly higher in the savanna-like upland matrix. The number of adults using ponds was positively correlated with the number of next-year's recruits in only one year. Recruitment rates were relatively low (maximum 175 captured/pond/yr), but juveniles were produced from most ponds in three of five years. Recruitment was negligible in 1994 because of ponds drying and in 1997 for unknown reasons. Juvenile body size differed significantly among years and ponds. Body size was negatively correlated with the number of juveniles exiting ponds in only one year, suggesting that intraspecific competition is only one of many factors affecting juvenile body size. Most emigration by metamorphic juveniles occurred May through August and was unrelated to rainfall. Dates of first emergence and length of emigration periods varied. A high proportion of juveniles with tailbuds and similar tailbud lengths in most months suggest that metamorphosis occurred throughout the emigration period. High variability in juvenile recruitment success and significant differences in body size among years and ponds suggests that each is influenced by factors at both a landscape (e.g., rainfall and pond hydrology) and within-pond scale (e.g., competition and predation).