5 (1) It is a defence to a charge under Section 3 or 4 that the person charged reasonably believed that he had legal justification, or permission of the occupier or a person authorized by the occupier, to enter on the premises or to do the act complained of.

and states later that

15 (2) No person may be prosecuted for contravening any notice given pursuant to this Act prohibiting entry or prohibiting activity on forest land if that person is . . . fishing, picnicking, camping, hiking, skiing or engaged in another recreational activity or engaged in a study of flora or fauna.

and defines 'forest land' as

15 (1) . . . a wooded area, forest stand, tract covered by underbrush, barren ground, marsh or bog . . .

We do not know if "tract covered by underbrush, barren ground, marsh or bog" would apply to the sand spit at Sperry's Beach, or if there is case law which has established a precedent.

NS Protection of Property Act