Galápagos shark

Open year-round with no closure; the split is a quality trade, not an access one. Cool season (Jun-Nov) means whale sharks, big-animal density, cold water and rough seas. Warm season (Dec-May) means calmer water, better visibility, more hammerhead schooling and more comfortable diving. Liveaboard permits are capped, so availability rather than weather is the practical constraint.

Same caveat as the sandbar shark.

South shore wreck diving runs year-round and is sheltered. North shore is seasonal in practice: winter (Nov-Mar) brings the swell Oahu is famous for and the Haleiwa tours cancel frequently. Because the wrecks are unaffected, the destination reads 'open' throughout, with the north-side caveat carried in the trip formats.