Section 36. For the purpose of protecting smelt and their spawn the director may close such portions of streams flowing into the coastal waters during the spawning season of such fish as he may deem necessary and may forbid the entrance into such portions of said streams by posting on or near such closed areas notices of such closing, giving the bounds thereof; provided however, that such closing and such prohibition of entrance shall not be for a period longer than sixty days in any one year. No person shall molest or disturb smelt or their spawn within such closed areas.