Epilogue: Factors implicated in amphibian population declines in the United States

Many species of amphibians have declined substantially in distribution or number of populations in the United States and globally, and a variety of anthropogenic and natural factors have been suggested as causal agents in these declines. Evidence for the causal action of these agents derives from many types of sources, all of which are important in seeking to understand amphibian population declines. This chapter evaluates the relative frequency of factors implicated as adversely affecting amphibian populations in the United States and examines taxonomic and geographic patterns in species status. It relies on species accounts to compile the factors implicated as adversely affecting populations and then assesses the status of each of these species with regard to the stability of its distribution and number of populations. Land use was identified as the most frequently implicated factor among both anurans and caudates.