The groups sent a letter Monday to Idaho Gov. C.L. "Butch" Otter as well as Idaho Department of Fish Game officials. The state has 60 days to respond.
Western Watersheds Project, the Center for Biological Diversity and Friends of the Clearwater contend that Idaho is violating the Endangered Species Act by allowing recreational trapping for bobcats that has led to the capture of three lynx in the last two years.
The groups say one was killed and two others were released.
The groups say the state needs a special permit from federal officials to continue the trapping.
State officials didn't return a call Tuesday from The Associated Press.