United States, Minnesota, Marshall, Thief Lake Wildlife Management Area. Thief Lake Wildlife Management Area; 3.6 mi N of the jnc of Rte 6 and Rte 89 (on the E side of Rte 89). T158N, R39W, Sec Thief Lake Wildlife Management Area; 3.6 mi N of the jnc of Rte 6 and Rte 89 (on the E side of Rte 89). T158N, R39W, Sec 30.. 158N 39W 30