Clerke Channel Drift

Meet the site

The Clerke Channel drift is the Rowley Shoals' adrenaline ride. On the incoming tide, oceanic water pours through the channel into the lagoon, and divers fly with it through bommies to the 'Coral Gardens' inside. Divernet lists a maximum of about 23 m, with sweetlips, bumphead parrotfish and cleaning stations along the way, and snapper schools in the incoming water; the channel is also called the Main Channel.

The tender drops divers outside and collects them inside the lagoon. Speed varies with the tide — the crew time it.

About the Rowley Shoals: three shelf-edge atolls — Mermaid, Clerke and Imperieuse reefs — rise from 300–700 m depths on the edge of the continental shelf about 260–300 km west of Broome. Mermaid Reef is protected in the Commonwealth Mermaid Reef Marine Park (a no-take national reserve); Clerke and Imperieuse form the State Rowley Shoals Marine Park, with sanctuary zones and limited recreational fishing areas. Clerke carries Bedwell Island and Imperieuse carries Cunningham Island and its lighthouse. More than 200 coral species and 700 fish species have been recorded, and only a few hundred divers visit each year in a season of a few weeks. The 2024–25 marine heatwave hit hard: AIMS surveys in April 2025 found very high (61–90%) coral mortality at Mermaid and Clerke across all habitats to 30 m, so hard coral cover is currently much reduced, although fish, sharks and the drama of the walls and drifts remain.

Planning notes: Advanced Open Water certification is recommended and the site is rated intermediate. Expect to spend most of the dive around 15 m, with a maximum of about 23 m. It can only be reached on a multi-day expedition or liveaboard, so it is usually one of several sites dived on the trip and choices are made by the crew on the day. Currents are significant, so timing around the tide is part of the plan. Best season: September–December (most trips October–November). Traffic: remote/expedition only.

What you might see

Bumphead parrotfish, sweetlips, snapper schools, trevally, reef sharks, cleaning stations

Location

Fast incoming-tide drift through the main channel of Clerke Reef over bommies into the lagoon's Coral Gardens, to about 23 m.

Facilities nearby

None – all services on the liveaboard (departures from Broome).