Gov. Sam Brownback says Kansas will join Oklahoma in suing the federal government over the addition of the lesser prairie chicken to its list of threatened species.

Brownback announced his state’s response Friday during a news conference. Oklahoma sued the U.S. Fish and Wildlife Service in federal court last week, challenging the process under which the federal agency was considering the listing.

The Kansas governor said there was no need for the federal agency to list the lesser prairie chicken as threatened because five states containing its habitat have developed a conservation plan. The states are Kansas, Colorado, New Mexico, Oklahoma and Texas.

The federal agency said in announcing its listing Thursday that there are fewer than 18,000 lesser prairie chickens, down 50 percent from the 2012 population.