North Horn

North Horn is Osprey Reef's stage. The atoll's northern point pinches into open ocean, walls fall away beyond sight on both sides, and a natural amphitheater at moderate depth seats divers for one of the Pacific's classic shark dives. Gray reef sharks own the arena, whitetips slide along the ledges, and silvertips make entrances from the blue; on winter trips hammerheads sometimes patrol the deep edge. Crews stage a controlled attraction that concentrates the action without turning it into a scrum, and even without bait the point delivers dogtooth tuna, potato cod, and the low hum of big-water tension.

その瞬間のために: Shark amphitheater over abyssal walls, silvertips from the blue, dogtooth tuna, ocean-clear water

地形: Coral point at the northern tip of Osprey Reef with a ledge amphitheater and walls into abyssal water

流れ（カレント）: The point splits oceanic flow; the amphitheater itself is usually workable while the corners run.

危険生物・リスク: Bottomless walls, current at the corners, and charged-up sharks during attractions; hold the ledge line.

保全: Shark attractions are conducted under operator protocols; sit where briefed and keep hands in.

ナイトロックス: ここでは効果的です——このエリアのプロファイルは、ナイトロックスが無減圧潜水時間を有意に延ばせる水深帯にあります（適切なトレーニングを受けていることが前提です）。