In any prosecution for a violation of state fish, game, wildlife, or natural resources laws, photographs of either wildlife or fish alleged to have been taken, possessed, sold, transported, or imported illegally are considered competent evidence of the wildlife or fish and are admissible if properly authenticated in any proceeding of the case to the same extent as if the wildlife or fish had been introduced as evidence. The photographer shall affix his signature and the date to the back of each photograph for identification purposes. When the photograph is so identified, is authenticated, and is admitted, it shall constitute substantive evidence.