No person, except for the Casco Bay Island Transit District, created by Private and Special Law 1981, chapter 22, may, directly, by lease or other arrangement transport passengers or property by vessel, for compensation, between the mainland of Cumberland County and Peaks Island, Great Diamond Island, Little Diamond Island, Long Island, Chebeague Island or Cliff Island, or between the islands mentioned in this section, without obtaining a certificate of public convenience and necessity from the commission authorizing the transportation. The district and any person who must obtain a certificate are ferries subject to the jurisdiction of the commission with respect to the service that requires authority. The commission shall specify in the certificate the business and operation of the ferry and shall attach to it at the time of issuance and from time to time after issuance reasonable terms, conditions and limitations as it determines necessary to maintain adequate transportation to these islands. The Casco Bay Island Transit District may assign or subcontract to another person any service for which it has a franchise. Regularly scheduled freight and passenger services are subject to the requirements of sections 5101‑A to 5101‑C. Unscheduled freight, tour, charter and taxi services are subject to the requirements of sections 5101‑D and 5101‑E.   [PL 1991, c. 774, §1 (AMD).]