The exercise of commercial fishing in Malagasy territorial waters is reserved for natural persons of Malagasy nationality or legal entities incorporated in Madagascar, using boats and vessels flying the Malagasy flag. The crew [including its captain] of a Malagasy vessel must be of Malagasy nationality.
TITLE IV - FISHERIES ACCESS REGIME
CHAPTER 1 - MARINE FISHING
Fishing access regime
Article 23: The practice of fishing is subject to registration with the Ministry in charge of Fisheries and Aquaculture.
The exercise of commercial fishing in Malagasy territorial waters is reserved for natural persons of Malagasy nationality or legal entities under Malagasy law, using boats and vessels flying the Malagasy flag.
[...]
Fishing rights for Malagasy vessels
Article 25: Any Malagasy vessel engaged in fishing:
- in waters under Malagasy jurisdiction:
a) must be registered in Madagascar or acquired in the form of credit in accordance with the legislation and regulations in force by natural persons of Malagasy nationality or Malagasy legal entities;
b) must be chartered by natural persons of Malagasy nationality or legal entities under Malagasy law;
[...]
From the collection of fishing products
Article 51: Without prejudice to the texts in force, any natural or legal person who collects fishery products from the maritime and continental waters referred to in Article 3a) and b) or in a port or landing place located on the Malagasy territory must cumulatively fulfill the following conditions:
- be of Malagasy nationality; 
- be a legal resident in Madagascar;
- hold a collection authorization issued by the Ministry in charge of Fisheries and Aquaculture. [...]" (LAW n° 2015 – 053 on the Fisheries and Aquaculture Code [google translation])
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CHAPTER 3 - Naturalization
Art. 2.3.01. - Application domain
All ships, with the exception of warships, are subject to the provisions of this chapter.
Art. 2.3.02. - Definition
Naturalization is the administrative act which gives the ship the right to fly the Malagasy flag with the privileges attached to it.
Art. 2.3.03. - Possession of an act of naturalization
Any Malagasy vessel setting sail must have its naturalization certificate on board.
The maritime administrative authority may exempt from the act of naturalization certain ships of less than ten tons of gross tonnage.
Art. 2.3.04. - Conditions of naturalization
To be naturalized Malagasy, a vessel must meet the following conditions:
1. belong either to a natural person residing on Malagasy territory, or to a company having its registered office in Madagascar;
2. produce the documents required in article 2.2.08;
3. have undergone a commissioning visit by the central safety committee;
4. be manned by a Malagasy crew. However, an exemption may be granted by the central service of the Merchant Navy in the event of a shortage of Malagasy officers. In return, the shipowner will pay a special contribution to the operating budget of the National School of Maritime Education of Mahajanga, the amount of which will be fixed by decree.
[...]
CHAPTER 2 - Conditions for exercising the profession of seafarer
Art. 3.2.01. - Nationality
The quality of Malagasy sailor is reserved for Malagasy nationals holding a passport or a sailor's identity booklet.
[...]
CHAPTER 9 - Function on board and composition of the crew
Art. 3.9.01. - Authority of the captain
The crew of a ship constitutes a hierarchical society under the authority of the captain who is the sole judge of the conduct of the expedition and the decisions to be made.
[...]
Art. 3.9.05. - Nationality of the crew
The crew of a Malagasy vessel must be of Malagasy nationality, except for derogation provided for in article 2.3.04 paragraph b, or have, subject to reciprocity, the nationality of one of the States having concluded with the Republic of Madagascar special agreements.[...]" (Madagascar - Law No. 99-028 of 3 February 2000 revising the Maritime Code" [google translation])
LAW n° 2015 – 053 on the Fisheries and Aquaculture Code [google translation]
Madagascar - Law No. 99-028 of 3 February 2000 revising the Maritime Code" [google translation]
[<a href="http://extwprlegs1.fao.org/docs/pdf/Mad162704.pdf">Law</a>],[<a href="https://www.apmf.mg/sites/default/files/inline-files/Code%20maritime.pdf">Code</a>]