Bynoe Harbour Entrance Reefs

Meet the site

Bynoe Harbour is a large, mangrove-lined inlet between the Cox Peninsula and Dundee, south-west of Darwin. The Marine Life Network describes the reefs and islands adjacent to the harbour entrance as easily accessed from Dundee, and the area is well known to anglers, crabbers and pearl farmers. It is not a mainstream dive destination, but its reefs offer an alternative when Fog Bay is too rough.

Published detail is limited. Expect fringing reefs around the entrance islands and banks, with turbid-water coral communities – massive, encrusting and plate corals, leather and soft corals, sponges and gorgonians – interspersed with rubble, sand and seagrass. Big tides flush the harbour twice a day, so currents at the entrance are strong and visibility changes rapidly through the tidal cycle.

Fish life is rich: golden snapper, fingermark, black jewfish, estuary cod, coral trout and grunter on the reefs, with queenfish, trevally and mackerel at the entrance on the run of tide. Turtles and dugong use the seagrass, and rays are common on the sand.

SS Brisbane lies on Fish Reef north of Bynoe Harbour and Quail Island, and many divers visiting the area will be doing so as part of a Brisbane trip. Bynoe itself suits self-sufficient, experienced Top End divers who can read tides and accept poor visibility. Divers who explore here are encouraged to record positions, depths and conditions and share them with Darwin Sub Aqua Club, as very little about these reefs has been written down, and the harbour's pearl leases and crab-pot lines should be given a wide berth when anchoring.

What you might see

Golden snapper, fingermark, black jewfish, estuary cod, coral trout, grunter, queenfish, trevally, Spanish mackerel, turtles, dugong, rays

Location

Reefs and islands at the entrance to Bynoe Harbour, the large inlet between Cox Peninsula and Dundee, south-west of Darwin.

Facilities nearby

Crab Claw Island (resort, boat ramp, fuel – check current availability) and Dundee Beach services. No air fills.