Maximizing pond biodiversity across the landscape: a case study of larval ambystomatid salamanders

Abstract

Loss or alteration of natural wetland habitats is a near ubiquitous global phenomenon. In the US, legislation mandates that all lost wetland habitats be replaced; manmade wetland habitats rarely have the same structural form or ecological function as natural wetlands. In the eastern US, these manmade pond habitats often serve as water sources for wildlife, but many are also utilized by amphibians for reproduction. Understanding the features that maximize species' abundance and diversity is critical to effective management. In this study, we surveyed for ambystomatid salamander larvae at 169 manmade ponds in a military training installation. Three species were present: Ambystoma maculatum, A. opacum and the regionally endemic A. annulatum. We estimated larval densities in each pond in relation to landscape-and pond-level covariates. Important factors relating to larval density were forest habitat surrounding each pond, canopy cover over a pond, the number of ponds within 300 m of the focal pond, presence of fish, slope of the pond basin, hydroperiod and amount of vegetation within the pond. Density estimates for each species were best predicted by different combinations of these factors, underscoring the need to provide a range of pond habitats to promote species diversity on the landscape. Our results indicate that manmade ponds are providing a valuable reproductive resource, but that future construction of ponds on the landscape will best serve the salamander and broader amphibian community if different combinations of hydroperiod and slope are utilized.

Habitat traits and species interactions differentially affect abundance and body size in pond‐breeding amphibians

“…To estimate the density of larval salamanders, we conducted repeated surveys of ponds within the focal area as described in Peterman et al . (). We sampled all focal area ponds using dip net sweeps and funnel traps standardized to pond surface area (Shulse et al .…”

“…We also measured pond characteristics that may have affected larval density and interactions (Peterman et al . ). We measured pond area assuming all ponds were ellipses.…”

“…A different analysis with these data found no difference in detection between dip net sweeps and funnel traps (Peterman et al . ). We estimated that each dip net sweep sampled an area of 1 m 2 and assumed that each funnel trap sampled a comparable area.…”

“…Additionally, abundance estimates made using N‐mixture models were imprecise; larval counts between days and sites were highly variable, necessitating modelling approaches that improved model fit at the cost of precision of abundance estimates (Peterman et al . ). As such, we used mean density estimates for all ponds in the focal area for our analyses.…”

Ecological Drivers of Cladoceran Diversity in the Central European City (Łódź, Poland): Effects of Urbanisation and Size of the Waterbody

“…This in itself represents only a fraction of the overall biological diversity present within ponds. Aquatic macrophytes Jeffries, 2008;Hassall et al, 2012), algae (Asencio, 2014), and Zooplankton (Rundle et al, 2002;Drenner et al, 2009) are also very well represented within ponds and all six species of native UK amphibians (including the protected Great Crested Newt (Triturus cristatus) and the Natterjack Toad (Epidalea calamita)) utilise ponds (Boothby, 1997b;O'Brien, 2014;Peterman et al, 2014). In addition, the following section outlines the ecological importance of ponds to freshwater biodiversity.…”