The Shannon II is one of the newer wrecks off 1770. Marinelife.org.au records that the 18.6 m fibreglass trawler capsized in 2004 after hooking an obstruction, floated upside down for about a week and eventually sank about 4 nm from the Barcoola wreck. Dave Harasti also lists her among the 'fish magnet' wrecks of the region.

Very little has been published about the dive itself. Marinelife.org.au notes only that she is attracting fish, and neither her depth nor her exact position is given. Given her proximity to the Barcoola, she is likely to lie in similar open, sandy ground, and in rich water like this any structure quickly gathers baitfish, cod and pelagics. As a fibreglass hull she will not corrode like the steel wrecks nearby, but she offers less relief and fewer internal spaces.

The Shannon II is included in this database because it is named in the regional dive references, not because it is an established dive. Anyone wanting to visit it would need local knowledge of the mark, a capable boat and a calm window, and would most likely combine it with the Barcoola on the same trip. Until more is known, plan it as a deep, exploratory dive for experienced divers with full boat support.

For visitors to 1770 without their own boat, the realistic diving options are the reef trips to Lady Musgrave Island and Fitzroy Reef, or technical wreck charters by arrangement with the local dive centre. Whatever the plan, carry emergency oxygen and a first-aid and evacuation plan: the 1770 offshore wrecks are 40 km or more from port and several hours from the nearest recompression chamber in Brisbane.

Boats launch at the Seventeen Seventy boat ramp on Round Hill Creek (at the end of Captain Cook Drive in the town of 1770, about 6 km north of Agnes Water; the town is 2 hours' drive north of Bundaberg via Rosedale or the coast road). The Round Hill Creek bar is shallow and should be crossed on the top half of the tide in a calm sea. The Shannon II lies about 4 nm from the Barcoola, which is roughly 44 km from the 1770 bar; no position is published, so obtain the mark from local divers or fishers.

Allow 60-90 minutes each way in a capable boat and drop a shot on the wreck.

These offshore sites lie north of the protection of K'gari and are exposed to the south-east trade winds that blow for much of the year, so they need a calm spell – winds under about 12-15 knots and seas under 1-1.5 m – for a small boat to make the run and anchor safely. North-westerly and westerly winds in winter give the flattest seas and the best visibility (up to 30-40 m on the outer wrecks). The wrecks are tidal: plan to dive at high-water slack, and prefer neap tides, as the current can run hard across open sand on springs.

The Round Hill Creek and Turkey Beach bars are shallow and dangerous on a low tide with swell. Summer brings northerly sea breezes, storms and cyclone risk (November-April).

Descend the shot onto the wreck, circle the hull once to orient yourself and then work slowly along it looking for resident fish. Depth is not published – plan conservatively and carry an SMB.

No regular operator – private boat or technical charter from 1770 (Dive Spear and Sport @ 1770 on demand).