TL;DR: The data suggest that R. sevosa has high population turnover among years and that most adults live less than 7 yr, and the viability of the population is contingent on consistent recruitment of juveniles with minimal years of reproductive failure.
Abstract: We studied variation in the population ecology of dusky gopher frogs, Rana sevosa Goin and Netting, in southern Mississippi from 1996–2001. Specifically, we measured adult size structure, adult survivorship, residency length within the pond, and juvenile recruitment using a drift fence that completely enclosed the study pond. Population size structure shifted among years because of lack of recruitment in previous years, adult mortality, and differential age at maturity. Age at maturity was 6–8 months for males and 24–36 months for females. Annual survival ranged from 65 to 92%; however, the rate at which adults returned to breed among years was low (16–22%). The average number of seasons that adults bred was 1.2, although nine individuals bred in 3–5 seasons. Our data suggest that R. sevosa has high population turnover among years and that most adults live less than 7 yr. Because of the low rate of return of adults among years and complete isolation of the population, the viability of the populat...
TL;DR: The objectives for this study were to develop and optimize eDNA survey protocols and assays to complement and enhance capture-based survey methods for these amphibian species.
Abstract: Environmental DNA (eDNA) is an emerging tool that allows low-impact sampling for aquatic species by isolating DNA from water samples and screening for DNA sequences specific to species of interest. However, researchers have not tested this method in naturally acidic wetlands that provide breeding habitat for a number of imperiled species, including the frosted salamander (Ambystoma cingulatum), reticulated flatwoods salamanders (Ambystoma bishopi), striped newt (Notophthalmus perstriatus), and gopher frog (Lithobates capito). Our objectives for this study were to develop and optimize eDNA survey protocols and assays to complement and enhance capture-based survey methods for these amphibian species. We collected three or more water samples, dipnetted or trapped larval and adult amphibians, and conducted visual encounter surveys for egg masses for target species at 40 sites on 12 different longleaf pine (Pinus palustris) tracts. We used quantitative PCRs to screen eDNA from each site for target spe...
TL;DR: Body size was negatively correlated with the number of juveniles exiting the pond in only one year suggesting intraspecific competition is one of many factors in the spatio-temporal dynamics of the Florida Gopher frog breeding and juvenile recruitment.
Abstract: We examined spatio-temporal dynamics of the Florida Gopher frog breeding and juvenile recruitment. Ponds were situated in a hardwood or pine-savanna matrix of upland forest. Movement was monitored from 1994-1999. Adult pond use was low but relatively constant. Juvenile recruitment was higher in the upland savanna matrix. Body size was negatively correlated with the number of juveniles exiting the pond in only one year suggesting intraspecific competition is one of many factors. Most immigration occurred in May through August and was unrelated to rainfall.
TL;DR: This study uses radiotelemetry to study movements and habitat use of juvenile and adult gopher frogs as they migrated from the same ponds following metamorphosis or breeding, and suggests that terrestrial habitats surrounding breeding ponds should be managed with frequent prescribed fire in order to maintain suitable terrestrial habitat for juveniles.
TL;DR: The breeding biology of Rana capito was studied for one breeding season at a 1.2 ha pond in Okaloosa County, Florida with a drift fence and pitfall traps and female oviposition site selection was examined using wading surveys.
Abstract: -The breeding biology of Rana capito was studied for one breeding season at a 1.2 ha pond in Okaloosa County, Florida. Frog movement was monitored with a drift fence and pitfall traps and egg deposition site selection was examined using wading surveys. A total of 301 unmarked adult frogs was captured, nearly half in February. Movement of immigrating frogs was positively correlated with rainfall. Frogs that entered and exited the pond only once, exited within an average of 38.5 m from the point of entry. Males spent more time in the basin than females and multiple-recaptured males stayed in the basin longer than single-recaptured males. Overall, the sex ratio did not differ from parity; however, nightly operational sex ratios were overwhelmingly male-biased. The eight-month breeding season (October through May) encompassed three major breeding events (one each in October, February, and April). A total of 146 complete egg masses was found, 67 of which contained an average of 2210 eggs. Frogs oviposited non-randomly, preferring rigid, vertical stems upon which to lay eggs. Each female deposited one egg mass. The gopher frog, Rana capito, is considered rare throughout its range (Martof, et al. 1980; Means, 1986; Dundee and Rossman, 1989; Godley, 1992), with habitat loss regarded as the greatest threat to its existence (Bailey, 1991). The terrestrial stage of the life cycle is threatened by habitat degradation or loss resulting from fire suppression, or habitat loss as a consequence of conversion for agriculture, plantation forestry, and real estate development. The larval stage is threatened by breeding site degradation due to drainage, siltation from road run-off, stocking of predatory fishes, and off-road vehicle use. Although various facets of its ecology have been investigated (Volpe, 1958; Franz, 1986; Bailey, 1990; Semlitsch et al., 1995), the natural history of R. capito remains poorly known. The only quantitative ecological study of R. capito was by Bailey (1990), who examined population size and structure, and environmental factors influencing movement of R. capito at a breeding site in Alabama. A better understanding of the breeding biology of R. capito is needed to address its conservation needs. My study was designed to gather data on (1) R. capito breeding migrations and breeding population size and structure, (2) the number of egg masses deposited per female, and (3) female oviposition site selection. MATERIALS AND METHODS Rana capito breeding biology was examined at Holley Pond, an isolated 1.2 ha depression marsh (Florida Natural Areas Inventory, 1990) on Eglin Air Force Base, Okaloosa County, Florida. Holley Pond is dominated by herbaceous vegetation, principally maidencane (Panicum hemitomon), spikerushes (Eleocharis spp.), hatpins (Eriocaulon compressum), bog-moss (Mayaca fluviatilis), floating hearts (Nymphoides aquatica), centella (Centella erecta), yellow-eyed grass (Xyris sp.), and panic grass (Panicum sp.). Holley Pond typically dries annually, and is comprised of three sub-basins that are connected at high water. Holley Pond occurs within an extensive, fire-suppressed longleaf pine (Pinus palustris)turkey oak (Quercus laevis) sandhill, and is immediately bordered by a narrow band of longleaf pine-live oak (Quercus virginiana) flatwoods. Frog movement into and out of Holley Pond was studied from 20 October 1994 to 19 May 1995 using a drift fence and pitfall traps. The drift fence was constructed from 30.5 m long x 0.9 m high rolls of black polypropylene silt-fencing, the bottom 15 cm of which was buried in the soil to prevent animals from burrowing beneath the fence. The ends of adjoining rolls were overlapped and secured with staples. Wooden stakes were used to support the fence. The fence, which completely encircled the pond, was 483 m long and an average of 15 m (range = 626 m) from the pond edge. Forty-seven pairs of 19 1 plastic buckets were sunk flush against both sides of the fence at approximately 10 m intervals. Each bucket was filled with water to a depth of approximately 2.5 cm and furnished with a sponge to provide cover for trapped animals and moisture if the water evaporated. With few exceptions, traps were checked daily in the morning and occasionally at night during peaks of frog migration. Buckets were covered on days when pitfalls were not checked. Frogs were measured with a plastic rule to the nearest mm (SVL) while flattened on their back, weighed to the nearest 0.5 gram with Pesola 217 This content downloaded from 157.55.39.106 on Mon, 25 Apr 2016 06:05:10 UTC All use subject to http://about.jstor.org/terms