U.S. Endangered Species Act Works, Study Finds

Maryann Mott
for National Geographic News
April 18, 2005
The longer an animal or plant species is protected under the U.S.
Endangered Species Act, the more likely it is to recover, a new study
says. The finding contradicts recent criticism that the act has returned
too few species to full health.

Researchers Martin Taylor, Kieran Suckling, and Jeffrey Rachlinski compared population trends of 1,095 listed species with three related factors: how long the species were listed, whether their habitat had been protected, and whether specific recovery plans were in place.

Overall, the study found that the Endangered Species Act (ESA) is effective, said Suckling, co-author of the study and policy director of the Center for Biological Diversity in Tucson, Arizona. The report is published in the April issue of the journal BioScience.

Three Key Factors

"We were able to identify three aspects that contribute to the act's success: recovery plans, critical habitat [protection], and the listing itself," he said. "Each of those has an independent contribution, and therefore we need to do more of those things."

Not everyone agrees that the ESA successfully preserves and protects wildlife. Critics argue that recovery of only 15 animals in 32 years indicates failure.

Suckling counters that the statistic is not a good measure of the act's effectiveness. "That would be like walking into an emergency room and saying, 'Look, everyone is sick. This hospital must be a failure.'"

A better measure, he said, is the extent to which the ESA is moving species toward recovery.

In particular, species that have had dedicated recovery plans in effect for two or more years showed greater rates of survival and recovery. Recovery plans lay out specific steps that need to be carried out to restore species to health.

Suckling adds that all recovery plans are not equal. Single-species recovery plans, for example, perform better than multispecies plans.

Since 2000, researchers noted, 73 percent of all new ESA recovery plans have been multispecies strategies.

"Wildlife agencies should reconsider the growing emphasis on multi-species plans, or at least take care to ensure that multi-species plans include the same level of attention to the needs of single species as is found in dedicated plans," the researchers write in the study.

Critical Habitat

Protecting "critical habitat"—areas that have biological or physical features essential to conservation—was also found to assist survival and recovery efforts. Such habitats, though, have rarely been designated since 1986, when new regulations restricted the U.S. Fish and Wildlife Service's ability to establish critical habitats.

Suckling explained that the regulations, introduced by the administration of President Ronald Reagan, created a feeling that protection of habitat was a redundant, unnecessary, and expensive procedure. In the last four or five years, however, courts have repeatedly struck down the 1986 regulations.

Recently more than 350 new critical habitats have been designated, the researchers wrote. "Our results suggest that if this progress continues, the proportion of species with recovering trends will increase significantly."


Attorney Reed Hopper of the Pacific Legal Foundation, a California-based organization that defends private-property rights, isn't convinced that the study shows a positive correlation between species improvement and the designation of critical habitat.

As proof, he points to the Fish and Wildlife Service's online database. The database shows that only 2 of the 15 animal species that have fully recovered have had critical habitats designated for them.

"Just looking at correlations would suggest that species without critical habitat are seven times more likely to recover," he said. "The type of pseudoscience used in this report adds nothing to the public debate on the effectiveness of the Endangered Species Act."

In March, the Pacific Legal Foundation filed two lawsuits against the Fish and Wildlife Service over the designation of 42 critical habitats

"There is no rhyme or reason why some areas are designated as critical habitat and no meaningful evaluation of the real costs to society of these designations," Hopper said. "As a result, Californians pay more for their homes, face higher taxes, and have seen their property unnecessarily turned into what amounts to wildlife preserves."

The Pacific Legal Foundation says that the Fish and Wildlife Service, when determining critical habitats, does little more than guess where species live.

The legal action was filed on behalf of associations throughout California that represent farmers, ranchers, developers, and other business owners.

A spokesperson for the Fish and Wildlife Service said the agency does not comment on active lawsuits.

Free E-Mail News Updates
Sign up for our Inside National Geographic newsletter. Every two weeks we'll send you our top stories and pictures (see sample).


© 1996-2008 National Geographic Society. All rights reserved.