Cod Spot is the headline dive of the Muiron Islands and is often called the most impressive dive near Exmouth. It lies about 100 m off South Muiron, a limestone reef of ledges, overhangs and bommies on a sandy floor at roughly 14–20 m, and it takes its name from the giant potato cod that live there. These metre-plus groupers approach divers closely and are the site's signature encounter.

The reef is also a manta cleaning station. Reef manta rays come in to hover over coral heads while cleaner wrasse pick them over, and patient divers who stay low and still can watch them circle for long periods. Winter and spring are the most reliable months for mantas around the Muirons. Beyond the headline animals the reef hosts clouds of golden cardinalfish in the overhangs, emperor, batfish, catfish, reef sharks, cleaner shrimp, nudibranchs, and green and hawksbill turtles resting under coral.

The Muirons sit in a World Heritage marine management area and before 2025 were known for dense hard and soft coral, gorgonians and sponges. The 2024–25 marine heatwave hit the northern Ningaloo region hard, and Dive Ningaloo paused all Muiron diving from August 2025 to reduce pressure on the reef. Some other operators continue to run Muiron trips when the weather allows; expect bleached or dead hard coral while the fish and big animals remain.

Cod Spot suits Open Water divers comfortable with a boat dive and some current. Visibility averages 5–20 m and is at its worst around the autumn coral spawn and plankton blooms, which are also what bring mantas and whale sharks into the area.

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.

Descend the mooring to the reef base at 14–18 m, find the potato cod around the main ledges and settle beside (not above) the cleaning station if mantas are present. Circuit the limestone outcrops with the current, rising to 8–10 m over the reef top for the second half, and return to the mooring for a safety stop.

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.