Quick answer. French Polynesia (Tahiti) is a French overseas collectivity, but it is not in the EU free-movement area. French nationals can work freely. Everyone else, including other EU citizens and UK passport holders, needs a work permit and a residence permit.
Do skippers and crew need a work permit in French Polynesia?
Unless you are a French national, yes. A non-French worker needs a work authorisation from the local labour directorate plus a residence permit. This is employer led and takes time, so start well ahead. This is the key surprise: being an EU citizen does not give you the right to work here.
Does the type of yacht matter?
On a bareboat charter (up to 12 guests who charter the yacht and hire a skipper) the rules above apply. On crewed charter, private yachts and superyachts, crew are often treated as seafarers and the route can differ with the flag and where the yacht is based, so confirm for that yacht. Working ashore follows ordinary work-permit rules.
Official source
French Polynesia public-service portal: service-public.pf (Direction du Travail and SEFI handle work authorisations). Confirm the current rules for your nationality before you travel.
What we ask of you
Keep your nationality correct in your profile.
If you hold a work permit for French Polynesia, tick the work-permit box.
Tell us early if your right to work is not sorted, so we can help before your dates.
Important
Immigration rules change and vary by nationality. This is general orientation, not legal advice, and Quarterdeck is not an immigration adviser. Confirm your own position with the official source above before you travel. We will not place you in French Polynesia if you do not hold the right to work. See also: Visas & work permits, overview.