BILLINGS, Mont. (AP) — The Biden administration said Thursday it was delaying a rule finalized in former President Donald Trump's last days in office that would have drastically weakened the government's power to enforce a century-old law protecting most wild birds.

The rule could mean more birds die, including those that land in oil pits or collide with power lines or other structures, government studies say. But under Trump, the Interior Department sided with industry groups that had long sought to end criminal prosecutions of accidental but preventable bird deaths.

While the new rule had been set to take effect Monday, Interior Department officials said they were putting it off at President Joe Biden's direction and will reopen the issue to public comment.

The migratory bird rule was among dozens of Trump-era environmental policies that Biden ordered to be reconsidered on his first day in office. Former federal officials, environmental groups and Democrats in Congress contend many of the Trump rules were meant to benefit private industry at the expense of conservation.

“The Migratory Bird Treaty Act is a bedrock environmental law critical to protecting migratory birds and restoring declining bird populations," Interior spokesperson Melissa Schwartz said. “The Trump administration sought to overturn decades of bipartisan and international precedent in order to protect corporate polluters.”

A federal judge in August had blocked a prior attempt by the Trump administration to change how the bird treaty was enforced. But the administration remained adamant that the law had been wielded inappropriately for decades to penalize companies and other entities that kill birds accidentally.

The highest-profile case brought under the law resulted in a $100 million settlement by energy company BP after the 2010 Gulf of Mexico oil spill killed about 100,000 birds.

Hundreds of other enforcement cases — including against utilities, oil companies and wind energy developers — resulted in criminal fines and civil penalties totaling $5.8 million between 2010 and 2018. U.S. Fish and Wildlife Service officials said relatively few cases end in criminal prosecutions.

More than 1,000 North American species are covered by the law — from the fast-flying peregrine falcon to numerous tiny songbirds and more than 20 species of owls. Non-native species and some game birds like turkeys are not on the list.

In 2017, the government stopped enforcing the law against companies and others in accidental bird deaths.

The move drew backlash from organizations advocating for an estimated 46 million U.S. birdwatchers. It came as species across North America already were in steep decline, with some 3 billion fewer birds compared with 1970, according to researchers.

A Trump administration analysis of the rule change didn't put a number on how many more birds could die. But it said some vulnerable species could decline to the point they would require protection under the Endangered Species Act.

Former federal officials and some scientists had said billions more birds could have died in coming decades under Trump's new rule. Advocacy groups, including the Audubon Society, had lobbied the Biden transition team to block it. They want the administration to set up a permitting system instead, so that wildlife officials can more closely regulate bird deaths.

“All indications are the birds need more protections and that the public strongly supports protections and loves birds,” said Steve Holmer with the American Bird Conservancy. “There has been great progress in finding solutions to bird mortality, and we're hopeful the administration will create a process to start implementing those solutions."

Industry sources and other human activities — from oil pits and wind turbines, to vehicle strikes and glass building collisions — kill an estimated 460 million to 1.4 billion birds annually, out of an overall 7.2 billion birds in North America, according to the U.S. Fish and Wildlife Service and recent studies. Researchers say cats kill the most birds; more than 2 billion a year.

Virginia’s Democratic governor blamed the Trump administration decision to end enforcement of the migratory bird law for the 2019 destruction of a nesting ground for 25,000 shorebirds to make way for a road and tunnel.

Many companies have sought to reduce bird deaths in recent decades by working with wildlife officials, but the incentive drops without the threat of criminal liability.

Industry groups that supported the Trump rule declined to say if they will fight to keep it.

“Our focus remains on working with the Biden administration in support of policies that support environmental protection while providing regulatory certainty,” said Amy Emmert, a senior policy adviser with the American Petroleum Institute.

Brian Reil with the Edison Electric Institute said utility companies that the trade group represents have a record of taking steps to protect wildlife and plan to work with the Biden administration.

The 1918 migratory bird treaty came after many U.S. bird populations had been decimated by hunting and poaching — much of it for feathers for women’s hats.

___

Follow Brown on Twitter: https://twitter.com/MatthewBrownAP.