The US Endangered Species Act has supported the ongoing recovery of California condors (Gymnogyps californianus).Credit: Mel Melcon/Los Angeles Times via Getty

The number of endangered species that the United States government has no recovery plans for has grown steadily over the past decade, according to an analysis published this month in Conservation Letters1. The plans detail the specific threats against a species as well as the ‘nuts and bolts’ strategies that will help the species recover. They are also mandated under the Endangered Species Act, the country’s key conservation law.

Researchers used publicly available data from the US Fish and Wildlife Service and the National Marine Fisheries Service, the agencies tasked with developing recovery plans, to determine how many species lacked such safeguards and how that has changed since 1978. They found that of 1,548 species eligible for a plan, 24.5% were currently still without.

Furthermore, the analysis showed that the number of recovery plans has always lagged behind the number of species listed, but that the gap between the two has widened since 2009, when the rate of species listings increased (See 'Endangered Plans').

“There isn’t enough funding for the services to close that gap,” says lead author Jacob Malcom, a conservation biologist at the Defenders of Wildlife in Washington DC. And without the plans, he says, people won't know what threatens a species and may be unwittingly preventing their recovery .