WASHINGTON, D.C. — California, Washington and 15 other states on Wednesday filed a lawsuit against the Trump administration’s weakening of the Endangered Species Act, a landmark law that has ensured the survival of the California condor, the grizzly bear and other animals close to extinction.

The lawsuit is the latest in a blitz of legal challenges to the president’s policies.

California Attorney General Xavier Becerra has sued the Trump administration more than 60 times over its agenda of dismantling Obama-era environmental and public health regulations. Though most of those cases haven’t been decided, judges have so far sided with California and environmental groups in cases concerning air pollution, pesticides and the royalties that the government receives from companies that extract oil, gas and coal from public land.

In a statement, Becerra said the administration’s rollback of the Endangered Species Act could have major repercussions for California, which has more than 300 species listed as endangered or threatened — more than any other mainland state.

“As we face the unprecedented threat of a climate emergency, now is the time to strengthen our planet’s biodiversity, not to destroy it,” Becerra said. “The only thing we want to see extinct are the beastly policies of the Trump administration putting our ecosystems in critical danger.”

The other states suing are Massachusetts, Maryland, Colorado, Connecticut, Illinois, Michigan, Nevada, New Jersey, New Mexico, New York, North Carolina, Oregon, Pennsylvania, Rhode Island, and Vermont. The District of Columbia and New York City also joined the lawsuit.

Interior Secretary David Bernhardt, a former oil lobbyist, has defended the new rules as a necessary modernization of a 46-year-old law that administration officials have called overly restrictive and expensive to follow. In Western states especially, where the federal government oversees large swaths of land that’s home to endangered species, the oil and gas industry, as well as farmers, loggers and ranchers, have fought to weaken the law.

Under the new rules, the federal government will be allowed to reduce the amount of land set aside for wildlife and to disregard the possible effects of climate change when predicting the future dangers species might face. For instance, animals that scientists say are likely to lose their habitats to melting sea ice and rising sea levels could have a harder time qualifying for protection.

The changes also mean that, for the first time, officials will be able to put a dollar figure on the cost of protecting an animal or plant.

Seven environmental and wildlife advocacy groups filed a separate lawsuit in August in the U.S. District Court for the Northern District of California challenging the changes to the act.

Building on the administration’s rollbacks, House Republicans from Western states announced earlier this week that they are reviving an effort to further diminish the act’s powers.

Yet among most Americans, the Endangered Species Act remains popular. A 2018 survey conducted by Ohio State University found that four out of five Americans support the act.