North Horn (Osprey Reef)

Meet the site

North Horn is Australia's best-known shark dive, and the reason many divers make the long trip to Osprey Reef. The site sits at the northern tip of the atoll, where a soft-coral-covered bommie and a natural coral-rubble amphitheatre at around 12 m lie at the top of a wall that plunges well over 1,000 m into the Coral Sea.

The shark dive is run as a controlled feed. Dive the World describes up to 26 divers sitting in a semicircle at about 12 m while a bait drum is released 10–15 m away; Mike Ball says 10–30 grey reef, whitetip reef and silvertip sharks typically attend, and silky sharks and the occasional hammerhead also appear. Marinelife.org.au records that feeds used baited milk crates. The sharks arrive quickly as the drum opens and circle closely before dispersing. Potato cod, red bass and dogtooth tuna join in. Mike Ball calls the site 'shark central'.

North Horn is also a superb wall dive in its own right. The bommie is draped in soft corals, fans and whips, the wall has ledges and caves, and the blue water beyond brings eagle rays, manta rays, yellow-tailed fusiliers, dogtooth tuna and even the rare sailfish. On good days visibility exceeds 40 m. Spirit of Freedom notes soft corals at 25–40 m and describes it as a natural amphitheatre on a wall of more than 1,000 m. A memorial plaque sits on the wall at about 32 m.

The feed is conducted by permitted operators under Parks Australia rules within the Coral Sea Marine Park. The Important Shark and Ray Areas assessment of Osprey Reef notes a monitoring receiver at North Horn, where operators sometimes attract and feed reef sharks. The dive suits divers with some experience in open ocean conditions.

What you might see

Grey reef, whitetip reef, silvertip and silky sharks, occasional hammerheads, potato cod, dogtooth tuna, red bass, yellow-tailed fusiliers, eagle rays, manta rays, rare sailfish; soft corals, sea fans, whips

Location

The northern tip of Osprey Reef, an isolated oceanic atoll in the Coral Sea about 350 km north-east of Cairns and 100 km beyond the Great Barrier Reef.