BILLINGS, Mont. – Republicans in Congress on Tuesday called for an overhaul to the Endangered Species Act to curtail environmentalists' lawsuits and give more power to states, but experts say broad changes to one of the nation's cornerstone environmental laws are unlikely given the pervasive partisan divide in Washington.

A group of 13 GOP lawmakers representing states across the U.S. released a report proposing "targeted reforms" for the 40-year-old federal law, which protects imperiled plants and animals.

Proponents credit the law with staving off extinction for hundreds of species — from the bald eagle and American alligator to the gray whale. But critics contend the law has been abused by environmental groups seeking to restrict development in the name of species protection.

Led by Rep. Cynthia Lummis of Wyoming and Rep. Doc Hastings of Washington state, the Republicans want to amend the law to limit litigation from wildlife advocates that has resulted in protections for some species.

And they want to give states more authority over imperiled species that fall within their borders. Also among the recommendations are increased scientific transparency, more accurate economic impact studies and safeguards for private landowners.

The Republicans said only 2 percent of protected species have been recovered despite billions of dollars in federal and state spending.

"The biggest problem is that the Endangered Species Act is not recovering species," Hastings said.

The political hurdles for an overhaul are considerable. The Endangered Species Act enjoys fervent support among many environmentalists, whose Democratic allies on Capitol Hill have thwarted past proposals for change.

Signed into law by President Richard Nixon in December 1973, the act has resulted in additional protections for more than 1,500 plants, insects, mammals, birds, reptiles and other creatures, according to the Fish and Wildlife Service.

Throughout its history, the law has faced criticism from business interests, Republicans and others. They argue actions taken to shield at-risk species have hampered logging and other economic development.

Complaints grew louder in recent months after federal wildlife officials agreed to consider protections for more than 250 additional species in settlements of lawsuits brought by environmental groups.

The endangered act was last amended in the 1980s. Given the current level of rancor between Democrats and Republicans, academics who track the law were skeptical that the latest calls for change would succeed.