These data have been collected by a collaborative and coordinated research network, SPARCnet (Salamander Population and Adaptation Research Collaboration network). We collected these data to examine patterns in seasonal and latitudinal variation in population density. This data can be used to estimate local salamander biomass, correcting for imperfect detection, and then compare these to estimates of biomass for other vertebrate species in North America that are known to have out-sized roles in ecosystem processes.