Using Anuran community diversity and Pseudacris crucifer to predict landscape quality across a land use gradient

As human-modified landscapes and climate changes proliferate, maintaining
biodiversity and understanding the function and quality of available
habitat is imperative. As anurans (frogs/toads) such as Pseudacris
crucifer, can be an indicator species of habitat quality and ecosystem
productivity, studying the anuran community in a mixed-land use region
provides an opportunity to better understand the relationship between
species and landscape modification. We explored the relationship between
anurans and ecosystem productivity by assessing the effects of spatial and
temporal heterogeneity on the presence of anurans across a land use
gradient. Within the Toledo Metropolitan Area, including the biodiversity
hotspot Oak Openings Region, we surveyed 67 different wetlands (N=1800)
over three years. There was a difference in community assemblage between
rural and suburban/urban habitats driven by human modification (impervious
surface), composition (landcover type), and productivity (NDVI). The
variation in spatial structure but lack of variation in temporal variables
suggests that spatial factors explain differences in the anuran community
among sites. Areas with more impervious surfaces, lower amounts of swamp
forest, and lower NDVI generally had significantly fewer anuran species (p
< 0.001, p = 0.001, p = 0.013), significantly lower average species
per survey (p < 0.001, p = 0.011, p = 0.005), and lower relative
abundance of anurans. Utilizing Generalized Linear Mixed Modeling, we
found that P. crucifer relative abundance (p = 0.006) and greater species
richness (p = 0.021) were the best predictors of ecosystem productivity.
Our research demonstrates the value of non-invasive anuran call surveys to
assess ecosystem productivity and species richness on a large scale, while
also offering a method to evaluate conservation efforts internationally.
This scalable approach can be applied anywhere with available
environmental data, and we recommend utilizing anurans as indicator taxa
for understanding ecosystem function, especially in human-modified
landscapes.