The Gap is the channel that separates North and South Muiron, and the Muirons' classic drift dive. Tidal water funnels between the islands and over a bottom of hard and soft coral, sponges and gorgonians at roughly 10–20 m, so the dive is a fast, effortless glide rather than a swim. Salt & Charcoal describes it as an exhilarating drift between the islands with moderate current; Australia's Coral Coast highlights its colourful hard and soft corals.

The current brings food, and with it fish: schools of fusiliers, trevally and snapper, reef sharks along the edges, turtles, and the chance of manta rays, dolphins or other pelagics passing through. The speed of the drift means a wide-angle look at the reef rather than macro hunting.

Because the flow is tidal, the dive is timed for a manageable part of the tide and run as a live-boat drift with a DSMB. It is best for divers with some drift experience; Advanced certification is sensible. When current is too strong, skippers substitute a moored site.

The Muiron corals were badly affected by the 2025 marine heatwave and Dive Ningaloo has paused Muiron trips; other operators may still run it. The drift remains worth doing for the ride and the fish life.

About the Muirons: North and South Muiron are two low, uninhabited limestone islands about 15 km north-east of the tip of North West Cape, protected within the World Heritage-listed Muiron Islands Marine Management Area. They are reached only by boat, which has kept the surrounding reefs relatively untouched. The waters are visited by dolphins, dugong, pilot whales and, from July to October, migrating humpback whales, and turtles nest on the island beaches in summer. The islands are well known for strong currents and changeable conditions, so dives are always chosen on the day by the skipper according to wind, swell and tide, and a day on the Muirons usually combines two sites with lunch on the boat in the lee of the islands.

Muiron trips leave Exmouth early (around 8:00–8:30 am). Operators collect divers or meet at their shop, then launch from Exmouth Marina (2 km south of town) or Bundegi boat ramp (14 km north). The islands lie about 15 km (9.8 nautical miles) north-east of the tip of North West Cape; the run takes roughly 1 hour from the marina and less from Bundegi, and it can be bumpy in a south-westerly.

Sites have public moorings; the boat ties off and divers giant-stride from the stern. Full-day double-dive trips with lunch on board.

The Muirons are exposed: the crossing and the western sides take the brunt of south to south-westerly winds and swell, and the afternoon sea breeze (often 15–25 knots, especially October–March) makes the return trip rough, so trips run early and are frequently cancelled for wind. Strong tidal currents run between and around the islands; drift sites such as The Gap are timed with the tide, and building swell often limits which side of South Muiron is diveable. Visibility 5–20 m, lower during plankton blooms and after the March–April coral spawn.

Cyclone season November–April. DBCA advises carrying a PLB because conditions can change quickly.

Enter together on the up-current side of the channel with a DSMB, descend quickly to 12–16 m and let the tidal flow carry the group over the coral. Stay close to the guide, hold depth near the bottom where the flow is gentler, and when the guide signals, deploy the DSMB and ascend together for a safety stop while drifting. The boat collects the group down-current.

Carry DSMB, reel and audible signal; PLB recommended by DBCA for boats.

Dive Ningaloo paused all Muiron Islands diving from 21 August 2025 after the coral bleaching event (replaced with Westside trips); Exmouth Dive & Whalesharks Ningaloo (Exmouth Diving Centre) runs Muiron dive and snorkel day trips when weather allows; Ningaloo Whaleshark Swim and Ningaloo Whaleshark-N-Dive offer Muiron dives on request. Check current status before booking.