The powers conferred by RCW 77.12.610 through 77.12.630 are in addition to all other powers conferred by law upon the department. Nothing in RCW 77.12.610 through 77.12.630 shall be construed to prohibit the department from operating wildlife information stations at which persons shall not be required to stop and report, or from executing arrests, searches, or seizures otherwise authorized by law.