Time and money make a difference in endangered species recovery

Since passage of the Endangered Species Act in 1973, over 1,300 endangered species have been protected in the United States and its territories. In the forthcoming issue of Ecology Letters, Male & Bean assess 14 years of endangered plant and animal status trends and show that the length of time species are protected, and the amount of money spent on their conservation are key variables in explaining trends.

Overall, about half of species protected are no longer declining and only 35 % of species protected for 13 years or more were still declining. Status trends are partly explained by taxonomy and funding. Species reported as receiving more money from the U.S. Fish and Wildlife Service or National Oceanic and Atmospheric Administration were much more likely to be improving or stable than those receiving less funding.

This study emphasizes the need to consider the ways in which agencies administer and the U.S. Congress funds the Endangered Species Act in judging whether the law is a success or failure in recovering biodiversity. This issue has become a major focus of political battles over this controversial environmental law.