Mass. Gen. Laws ch. 131 § 10
Whenever such wildlife sanctuary has been established by an order as provided in section nine, no person, except as authorized by the director under clause (2) of section four, shall hunt, trap or take any bird or mammal within said sanctuary, nor shall any person enter such sanctuary with a firearm, trap, snare, or other device of any kind or description adapted to the killing, taking or injuring of birds and mammals, nor shall any person take, molest, disturb or destroy any nest, eggs or young of such birds or mammals or remove the eggs or young from the nest.
The established borders of a wildlife sanctuary, including any entry path or way, shall be posted to provide conspicuous notice to the public of the designation of the land as a wildlife sanctuary and of the prohibitions under this section. If the required notice has not been posted, a person shall have an affirmative defense against an alleged violation of a prohibition under this section.
The director shall adopt regulations regarding the posting of wildlife sanctuary land that shall include a requirement that notice shall be posted in a conspicuous manner for the type of terrain at intervals of not greater than 300 feet in distance along the borders of the land.
Mass. Gen. Laws ch. 131, § 10