Endangered Species Act Isn't Working Well, Study Finds

Most species aren't protected until their numbers dwindle so low they're hard to save.

Giant Panda, Ailuropoda melanoleuca, Wolong Giant Panda Research Center, China
Giant pandas have protections under the ESA. Mike Powles / Getty Images

Since the Endangered Species Act was passed in 1973, it has helped hundreds of species avoid extinction in the United States. The strong conservation policy has been used as a model in other countries. But it’s not as successful as it could be, a new study finds.

Researchers have discovered that most species are not being protected until their numbers have dwindled so low that their chance of recovery is slim.

“The ESA is an incredibly powerful, ambitious law for protecting our imperiled wildlife. Yet, for decades, the agency primarily responsible for operationalizing the ESA—the U.S. Fish and Wildlife Service (USFWS)—has been starved of resources,” lead author Erich Eberhard from Columbia University’s Department of Ecology, Evolution, and Environmental Biology, tells Treehugger.

“As a result, we are very slow to give species the protections that they deserve. We typically wait until species are extremely rare and thus at extreme risk of extinction, and then, when a species is finally listed, FWS is straining its resources to try to recover it.”

In 1993, a study found that few species received protection under the ESA until their populations became very small. The study found that species listed for protection under the act had dwindled to very tiny numbers: on average, just 1,075 individuals for vertebrates, 999 for invertebrates, and 120 for individuals for plant species.

For the new study, researchers repeated the methodology in the earlier research to see if protections have become better since the problem was first noted. They also looked at trends in “wait times”—the amount of time between when a species is identified as potentially needing protection and when it actually receives protection under the ESA.

“Our analysis suggests that, in the nearly 30 years since attention was first brought to this problem, we have not become more proactive in protecting imperiled species,” says Eberhard. 

The researchers found that the population sizes of species when they first became protected under the ESA are not statistically different from those in the 1993 study. The findings showed that the median population of vertebrates when listed is 999 individuals, invertebrates is 536, and plants is 192.

“That's just too low,” he says.

They also discovered that there are long wait times between when a species is identified as likely needing protection and when they actually receive them.

“At the same time, the number of species protected under the ESA has grown, and the funding provided to FWS hasn't kept pace,” Eberhard says. “The result, as we report in our study, is that there was less funding available for the management of imperiled species, on a per species basis, in 2020 than there was in 1985.”

The results of the study were published in the journal PLOS ONE.

Strength Is Undercut

There have been several thousand species listed on the ESA over the past nearly five decades, and 99% of the listed species have avoided going extinct. But researchers point out that only 54 species—like the bald eagle and American alligator—have recovered so well that they no longer need protection.

“Since it was passed in 1973, the ESA has served as an inspiration and model for conservation policy in other countries around the world. It's considered one of the strongest laws for wildlife conservation on Earth,” Eberhard says. “Yet, our analyses suggest that its strength is being undercut by a pattern of listing species too late, with too small of populations, and with too little funding for listing activities and recovery actions.”

Researchers say that the findings are timely due to the upcoming December meeting of the United Nations Convention on Biological Diversity. The members will finalize a plan for conservation efforts globally through 2030.

“I can say that our study paints the current state of the ESA as a bit of a cautionary tale for aspirational conservation policy,” says Eberhard.

Polls over the years have demonstrated that most Americans support a strong ESA to protect vulnerable wildlife. And the ESA has the strong policy, if used correctly, to do that.

Eberhard says: “What our study suggests is that we need a more serious investment of resources into the U.S. Fish and Wildlife Service—which has had success when the necessary resources are in place—so that the ESA can be operationalized as intended, imperiled species can receive protection more quickly, and more species can be recovered.”

View Article Sources
  1. lead author Erich Eberhard from Columbia University’s Department of Ecology, Evolution, and Environmental Biology

  2. Eberhard, Erich K., et al. "Too Few, Too Late: U.S. Endangered Species Act Undermined by Inaction and Inadequate Funding." PLOS ONE, vol. 17, no. 10, 2022, p. e0275322., doi:10.1371/journal.pone.0275322

  3. "Listing Species Under The Endangered Species Act". Biological Diversity.

  4. "U.S. Fish and Wildlife Service Proposes Delisting 23 Species from Endangered Species Act Due to Extinction." U.S Department of the Interior.