In principle, only nationals of the Netherlands may be appointed as captain of a Dutch flagged fishing vessel. Exemptions may be granted to EU/EEA nationals.
"Article 29
1 On Dutch ships, only Dutchmen are appointed as captains.
2 Exemption from the requirement referred to in the first paragraph may be granted for fishing vessels by ministerial regulation, subject to conditions or restrictions.[...]" (Seafarers Act of 11 December 1997; consolidated version in force on 01-02-2002; Article 29 [google translation])
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"Article 1
Exemption from the requirement in Article 29, first paragraph, of the Seafarers Act is granted for persons who have the nationality of a Member State of the European Union, of another State that is a party to the Agreement on the European Economic Area, or of the Confederation of Switzerland, and who is appointed as captain of a Dutch sea-going fishing vessel.[...]" (Regulations for exemption from the nationality requirement for sea fisheries captains (Minister of Transport, Public Works and Water Management, 08.23.2003); subsequently amended; Article 1 [google translation])
Seafarers Act of 11 December 1997; consolidated version in force on 01-02-2002; Articles 29 and 30
Regulations for exemption from the nationality requirement for sea fisheries captains (Minister of Transport, Public Works and Water Management, 08.23.2003); subsequently amended; Article 1
[<a href="https://wetten.overheid.nl/BWBR0009124/2002-02-01">Act</a>],[<a href="https://wetten.overheid.nl/BWBR0015476/2003-08-23">Reg</a>]