A federal judge has tossed a rancher’s claim that he should still have the right to use federal land in New Mexico after it was revoked for killing a wolf.

Craig Thiessen killed an endangered Mexican wolf in Gila National Forest six years ago and has since argued that he should still be allowed to graze his cattle on the 48,000 acres (about 194 square kilometers) of public land, the Santa Fe New Mexican reported  on Friday.

That argument was rejected this week by U.S. Magistrate Judge Gregory Fouratt.

Thiessen pleaded guilty in 2018 for killing the wolf. He faced a year of probation and a $2,300 fine. Later that year, the U.S. Fish and Wildlife Service revoked his company’s permit to graze cattle on the public land.

A court document said he had 286 cows and 143 calves on the property. Thiessen has continued legal action in an attempt to keep his cattle on the land. The federal fish and wildlife service has sued Thiessen to remove the cows.

Hayden Ballard, an attorney who has represented Thiessen, did not respond to a request for comment on Friday by the newspaper.

Representatives from four conservation groups said in a statement that Thiessen had given up his privileges to use the public land after his actions.

Greta Anderson from the Western Watersheds Project accused Thiessen on Friday of animal cruelty by killing the wolf. The Santa Fe New Mexican reported that numerous accounts said the young wolf’s leg was caught in a trap and it was then struck with a shovel.