Any person, finding or taking possession of personal property not his own, of the value of $20 or more, shall immediately return such property to its lawful owner or custodian. If the lawful owner or custodian cannot be immediately found or ascertained, the property shall be turned over to a member of the regional park police, or if no member of the regional park police can be located, an employee of the office, who shall issue a receipt therefor.