Mont. Code Ann. § 87-3-121

The commission shall adopt rules to regulate contests, in accordance with the provisions of 87-6-214, by a person, firm, or club that intends to offer or give a prize, gift, or anything of value in connection with or as a prize for the taking, capturing, killing, or in any manner acquiring fish that are protected under Title 87. The commission's rules must be based on the commission's duty under Title 87 to protect, preserve, and propagate fish in the state.