Kauai

Most operators run Niihau and Lehua trips between May and September when seas and winds align. Build a buffer of 1-2 days because crossings are weather dependent. Winter trips are rare due to swell and wind. If conditions shut down, shift to Poipu and Koloa south shore sites which are viable most of the year.

Non-residents must reserve entry. Choose either a parking-plus-entry pass or a shuttle ticket that includes entry. Time slots fill quickly in summer. If you only have snorkel plans, consider the shuttle to avoid limited parking. Bring your reservation QR and photo ID.

For year-round access, base near Poipu and Koloa on the south shore. You will be close to Koloa Landing, Sheraton Caverns, and boat ramps. If your trip is in late spring or summer and you want north shore snorkeling, consider splitting time between Poipu and Princeville or Hanalei.

On the water keep 100 m from humpback whales and 50 m from spinner dolphins. Give turtles 3 m and monk seals 15 m or 45 m for moms with pups. Never touch or chase wildlife. These distances apply on land and in water for listed species.

Yes, especially at Koloa Landing on calmer days. The sloping reef, multiple entry options, and easy navigation suit training and first ocean dives. Use a flag, check for surge, and time dives for mornings before winds build. In winter, focus on south shore pockets and avoid the north shore.

No general marine tag is required. You only need reservations for Haena State Park on the north shore and permits for overnight camping in Napali Coast State Wilderness Park. Boat dives and Niihau trips are handled by licensed operators.

Most divers are comfortable in a 3 mm full suit year-round, with water typically around 24°C to 28°C. Photographers or those prone to cold can add a hooded vest. Freedivers often use 2-3 mm two-piece suits.

Winter north swells make the north shore unsafe for snorkelers. Choose lifeguarded south shore pockets and avoid brown water after storms. In summer, the north shore settles and offers long, clear drifts. Mornings are best before trades pick up.

Only with a guide, proper lighting, and zero surge. Caverns like those at Sheraton require overhead discipline. Never enter overhead environments on snorkel or while freediving, and skip cavern dives entirely during swell or strong surge.

Yes. From December to April, look from south and west-facing lookouts for blows and tail slaps. Bring binoculars and keep your distance if on the water. Boats often post a dedicated whale spotter in season.