The lesser prairie chicken, a flamboyant, stocky bird that once covered America's grasslands in the hundreds of thousands but whose population has dwindled to roughly 30,000, will be protected by the US Fish and Wildlife Service.

The species federal protection will be given to the two populations of the chicken when the rule takes effect in January.

The birds' northern population is spread across the plains of central and western Kansas, central Oklahoma and the northeast Panhandle of Texas.

The status is less urgent than "endangered," but it will give the chickens in the north the same protections as those in the south.

The agency's southwest regional director said that the decline of the lesser prairie chicken is a sign that the native prairies are in danger.

She said that the agency would work with all stakeholders to make sure the protections go smoothly.

The plight of the lesser prairie chickens has been entwined with the pursuit of oil and gas producers. The companies have long claimed that federal protections for the lesser prairie chickens would curtail oil production, with the law limiting where an oil rig can be placed if it could result in a further loss of habitat for the birds.

The US Fish and Wildlife Service has been told that quick action was needed to slow the loss of the beloved, showy little birds. Men inflate their air sacs with their feet against the ground, causing a loud noise that can be heard as far away as half a mile.

The species was listed as being at risk of extinction by the U.S. government. The move was criticized by oil and gas companies and some Republican legislators. At the time, environmental groups said that the chickens needed to be listed as extinct.

The government was sued by the oil and gas association for not taking into account voluntary conserver efforts. The judge in the western district of Texas ruled in favor of the association.

A new petition was filed in 2016 asking for the chickens to be protected by the federal government. Progress on the petition was stopped by the Trump administration.

The agency promised oil and gas companies, renewable energy developers, ranchers and agricultural workers that it would work to make sure their activities continued.

Some opponents of the measure might think that 21 million acres of land will be off limits to energy production, but that is not the case, according to Clay Nichols.

There are only four million acres of suitable habitat for the lesser prairie chicken and many industries will be allowed to continue operations in those acres.

There is not much overlap between where the birds live and where the oil is being developed.

New activities that result in the loss of habitat will most likely be prevented by the law.

Oil and gas companies don't think there's any need for protections.

Ben Shepperd said in a statement that the decision was reckless and irresponsible.

Tens of millions of dollars have been spent to protect the species, as a result of oil and gas companies investing significant resources.

The agency's decision was condemned by Roger Marshall and Jerry Moran, both Republicans of Kansas.

The health of the lesser prairie chickens is indicative of the health of the country's grasslands, which are important to the Great Plains.

Michael Robinson, a senior advocate with the Center for Biological Diversity, said by phone on Thursday that energy companies have accelerated habitat losses for the chickens in Texas and Oklahoma.

Mr. Robinson said that the smaller groups of lesser prairie chickens that can't interact with other groups weaken and disappear. That is a recipe for disaster.