Data for "Anuran Populations Exhibit Species-specific Responses to Precipitation Conditions"

Flooding and drought events are increasing in frequency and severity across the Midwest of the USA. Increased variability of water on the landscape can impact wildlife populations, especially those that rely on water throughout their life cycle. We modeled anuran abundance for six species that range statewide in Iowa, USA using data from the Multiple Species Inventory and Monitoring program and the PRISM Group. Timed searches were conducted on at least five occasions between mid-April and mid-October each year from 2007-2022, with a total of 4485 surveys across 396 sites. We used Bayesian hierarchical N-mixture models to estimate adult abundance of each species while accounting for imperfect detection probability. We tested three hydric metrics (precipitation mean and variance, and drought index) during each of three temporal periods (current year, 1-year prior, 2-years prior) to determine the weather conditions that best explain variation in abundance for each species. Responses to hydric metrics were species-specific, and mean precipitation tended to be the strongest predictor for nearly all species. Regardless of the hydric metric, abundance was often best predicted by the hydric conditions one year prior. Boreal chorus frogs and American toads responded similarly to each hydric metric and time scale, and bullfrog and Blanchard’s cricket frogs showed similar patterns to each other. These emerging commonalities between species, suggest that conservation should focus on measures to support species assemblages based on shared ecological characteristics to maximize conservation benefit.