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Hotels, dive operators, gear, and how to get here are on the Kona Coast location page.
Overview
A drowned volcanic tuff cone in the ʻAlalākeiki Channel between Maui and Kahoʻolawe, breaking the surface as a 0.6 km crescent that shelters a shallow lagoon famous for water clearer than almost anywhere in Hawaii — 30 m of visibility is an ordinary day, 45 m happens. Inside the arms, a coral-and-rubble reef at 6–18 m holds dense reef fish: schooling black durgon, yellow tang, Moorish idols, raccoon butterflyfish, parrotfish and patrolling bluefin trevally over beds of red pencil urchins. The crater's open back side is a different dive entirely — a sheer wall plunging past 60 m into blue water where whitetip reef sharks, eagle rays, the occasional manta and even Galápagos sharks cruise the drop-off. Protected since 1977, it is one of the most-dived sites in the islands.
Briefing note
State Marine Life Conservation District and Seabird Sanctuary since 1977 — no fishing, feeding, anchoring or taking anything; mooring buoys only. The sheltered interior suits open-water divers and snorkelers, but the Back Wall is an advanced drift dive over a 300 m+ drop-off with real current and depth. Trade winds pick up by late morning and afternoon trips are often choppy and lower-visibility. Humpback song is audible underwater roughly December–April.
What you'll see
12 species curated- year-roundBluefin trevally
- year-roundYellow tang
- year-roundBlack durgon
- year-roundMoorish idol
- year-roundRaccoon butterflyfish
- year-roundWhitetip reef shark
- year-roundSpotted eagle ray
- year-roundGreen sea turtle
- year-roundRed pencil urchin
- rareReef manta ray
- seasonalHumpback whalePeak: Dec · Jan · Feb · Mar
- rareWhale shark
Conditions
| Month | Water | Visibility | Current |
|---|---|---|---|
| Jan | 24–25 °C | 15–30 m | mild |
| Feb | 23–24 °C | 15–30 m | moderate |
| Mar | 23–24 °C | 15–30 m | moderate |
| Apr | 24–25 °C | 20–38 m | mild |
| May | 24–26 °C | 20–40 m | mild |
| Jun | 25–26 °C | 20–40 m | mild |
| Jul | 26–27 °C | 20–45 m | mild |
| Aug | 26–27 °C | 20–45 m | mild |
| Sep | 26–27 °C | 20–45 m | mild |
| Oct | 26–27 °C | 20–40 m | mild |
| Nov | 25–26 °C | 15–35 m | moderate |
| Dec | 24–25 °C | 15–30 m | moderate |
Season calendar
Peak season highlighted · current month outlined
Next step
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