Manta Ray Bay, at the northern tip of Hook Island, is the Whitsunday Islands' signature fringing-reef site and the stop almost every day boat heading north from Airlie Beach makes. It lies about 25 km from Airlie, in a Marine National Park green zone, with six public moorings used on a first-come basis and no anchoring permitted. The bay's reef slopes from shallow coral into valleys, caves and swim-throughs, with bommies reaching about 25 m at its outer edge.

It is famous for its resident fish. George, a giant humphead Maori wrasse up to 2 m long, has been greeting snorkellers and divers for years, and Trevor, a large male giant trevally, is a regular; schools of hundreds of yellowtail fusiliers, batfish, coral trout and parrotfish fill the water column. From May to September, as the name promises, manta rays with wingspans up to 5 m cruise the bay.

The reef has a hard recent history. Severe Tropical Cyclone Debbie in March 2017 hit northern Hook Island directly, and the ABC reported that the 'entire substrate' of Manta Ray Bay had been wiped out, leaving only the large bommies standing. Recovery since has been steady, and operators now describe the reef as recovering well.

To support that recovery and draw visitors back, the Ngaro Underwater Marine Sculpture Trail placed two works here: a 3.8 m aluminium Manta Ray by Adriaan Vanderlugt, made with Traditional Owners, at 5–6 m, and Migration of the Mantas by Brian Robinson at 4–10 m. It suits all levels: snorkellers and Discover Scuba divers in the shallows, certified divers on the deeper slope. Mornings before the crowds arrive are best.

Boat only. Northern Hook Island is about 22–28 nautical miles from Airlie Beach – roughly 45–75 minutes by fast day boat from Coral Sea Marina or Port of Airlie, or about 1 hour from Hamilton Island marina. Day tours that stop here include Ocean Rafting, Red Cat Adventures (Thundercat), Whitsunday Dive Adventures and Explore Group (from Airlie and Hamilton Island); overnight sailing and bareboat charters also visit.

Private and bareboat skippers must use the public moorings (time-limited, first come first served) and observe no-anchoring areas marked by reef protection markers; bareboat operators restrict where hirers may go. Parking at Airlie is available near Coral Sea Marina and the Port of Airlie.

The northern Hook Island bays face north and are sheltered from the dominant south-east trades (15–25 knots April–September), but they are open to northerly winds and swell (common October–March) and to very strong south-easterlies that wrap around the headlands. Tidal currents through the islands are strong on spring tides (tidal range up to about 4 m) and can make points and bay entrances difficult – plan dives at slack water and neap tides where possible. Visibility is usually 5–15 m, dropping after strong winds, big tides and wet-season rain.

Manta rays visit May–September. Marine stinger season (box jellyfish and Irukandji) runs roughly November to May – wear a full-length stinger suit or wetsuit with hood and gloves, carry vinegar. Cyclone season November–April; tropical lows and cyclones can close sites and damage coral (TC Yasi 2011, TC Debbie 2017).

Severe Tropical Cyclone Debbie (March 2017) badly damaged the fringing reefs of northern Hook and Hayman islands; recovery is ongoing. Manta Ray Bay is unsuitable as an overnight anchorage because of exposure and currents.

From the mooring, descend to the coral slope and follow it along the bay's edge at 8–15 m through the valleys and swim-throughs, dropping to 20–25 m at the outer bommies if experienced. Return shallower past the Ngaro trail manta sculptures (5–6 m) for the safety stop.

Ocean Rafting (Northern Exposure/Southern Lights – daily snorkel stops on northern Hook), Red Cat Adventures Thundercat (daily, Mantaray Bay/Stonehaven), Whitsunday Dive Adventures (certified and Discover Scuba day trips, several times a week), Explore Group (dive and snorkel from Airlie Beach and Hamilton Island, daily), plus overnight sailing vessels and bareboats.