Big game hunter Corey Knowlton’s long wait to kill an endangered black rhinoceros in Africa is finally over.

In a decision Thursday that’s certain to rile animal rights activists, the U.S. Fish and Wildlife Service removed the last hurdle in the way of Knowlton’s quest. More than a year after the wealthy Texan submitted the winning $350,000 bid for a Namibian government permit at a Dallas auction to shoot the animal, the agency announced that it approved his application for a separate U.S. permit to import the animal’s carcass back home as a trophy.

As soon as Knowlton verifies that funds sitting in an escrow account have been wired to Namibia, a Fish and Wildlife official said, the permit is his.

The agency explained its controversial decision by saying hunting rhino bulls such as the one Namibia selected for Knowlton is a necessary evil to increase the population of a species in peril. Older rhinoceros bulls are known to keep younger bulls from mating with cows in their groups even after the elder males can no longer reproduce. After studying Namibia’s conservation program, the agency deemed that culling certain bulls “will benefit … the species,” according to a statement.