Remarkable Amphibian Biomass and Abundance in an Isolated Wetland: Implications for Wetland Conservation

Abstract

Despite the continuing loss of wetland habitats and associated declines in amphibian populations, attempts to translate wetland losses into measurable losses to ecosystems have been lacking. We estimated the potential productivity from the amphibian community that would be compromised by the loss of a single isolated wetland that has been protected from most industrial, agricultural, and urban impacts for the past 54 years. We used a continuous drift fence at Ellenton Bay, a 10-ha freshwater wetland on the Savannah River Site, near Aiken, South Carolina (U.S.A.), to sample all amphibians for 1 year following a prolonged drought. Despite intensive agricultural use of the land surrounding Ellenton Bay prior to 1951, we documented 24 species and remarkably high numbers and biomass of juvenile amphibians (>360,000 individuals; >1,400 kg) produced during one breeding season. Anurans (17 species) were more abundant than salamanders (7 species), comprising 96.4% of individual captures. Most (95.9%) of the amphibian biomass came from 232095 individuals of a single species of anuran (southern leopard frog[Rana sphenocephala]). Our results revealed the resilience of an amphibian community to natural stressors and historical habitat alteration and the potential magnitude of biomass and energy transfer from isolated wetlands to surrounding terrestrial habitat. We attributed the postdrought success of amphibians to a combination of adult longevity (often >5 years), a reduction in predator abundance, and an abundance of larval food resources. Likewise, the increase of forest cover around Ellenton Bay from <20% in 1951 to >60% in 2001 probably contributed to the long-term persistence of amphibians at this site. Our findings provide an optimistic counterpoint to the issue of the global decline of biological diversity by demonstrating that conservation efforts can mitigate historical habitat degradation.

Man-made Mediterranean temporary ponds as a tool for amphibian conservation

“…Therefore, it will be crucial to determine if species of high conservation concern can colonize artificial MTPs within these brief periods. Moreover, quantifying the productivity of these MTPs will provide an estimate of how well creating new aquatic habitats maintains local biodiversity (Gibbons et al, 2006).…”

Serosurveillance of Eastern Equine Encephalitis Virus in Amphibians and Reptiles from Alabama, USA

“…Because of their high energy conversion efficiency, ectotherms typically represent a large portion of the vertebrate biomass in many ecosystems, [9][10][11][12][13] and may therefore greatly influence transmission dynamics, either as virus amplifiers or dilution hosts. This feature may be especially true of EEEV because it is found in hardwood swamps where amphibians and reptiles are particularly abundant.…”

Design guidelines for integrating amphibian habitat into golf course landscapes

“…Amphibians are key components in wetland and terrestrial ecosystems as they are often the most abundant vertebrates present in terrestrial habitats (Blaustein & Kiesecker, 2002;Gibbons et al, 2006;Ranvestel, Lips, Pringle, Whiles, & Bixby, 2004;Wake, 1991) and they serve as both prey and predators for a diverse range of organisms (Davic & Welsh, 2004;Harding, 1997). Declines in amphibian populations will have ecological impacts in both aquatic and terrestrial ecosystems (Halliday, 2008;Ranvestel et al, 2004).…”