Ala. Code § 13A-8-6

A person commits the crime of theft of lost property if he actively obtains or exerts control over the property of another which he knows to have been lost or mislaid, or to have been delivered under a mistake as to the identity of the recipient or as to the nature or the amount of the property, and with intent to deprive the owner permanently of it, he fails to take reasonable measures to discover and notify the owner.