Shearwater Island is a small islet – roughly 100 m east–west and 150 m north–south – immediately south of Sugarloaf in the Admiralty Islets, and Michael McFadyen calls it 'one of the most interesting dive sites at LHI'. The dive covers the western and southern sides of the island, where a series of rocky fingers jut out from the shore and drop to sand at about 16 m. The main reef sits at around 10 m, which keeps the dive shallow and bottom times long.

What sets it apart is coral cover. McFadyen describes all the rocks as covered in hard coral, with abundant gorgonias, and compares the coverage with the Great Barrier Reef – a striking thing to see at the southern limit of coral reefs. The gutters between the fingers are where the fish concentrate: moray and other eels, firefish, butterflyfish, anemonefish in their hosts, and schools of trevally and almaco jacks overhead. Humphead wrasse and Spanish dancers are both recorded, and there are nudibranchs and flatworms for macro photographers.

McFadyen's May dive had at least 40 m visibility and 21.8°C water. The site is a good option in southerly winds, when the southern dive sites of the island are rough and the Admiralty Islets are in the lee.

The route is simple: west through the boulders of the main reef, south-east through the finger gutters, then back north to the anchor. It suits Open Water divers and snorkellers can see a good deal of the top of the reef on calm days, though the boat does not usually carry snorkellers here. For photographers wanting a coral-rich shallow site with good light, this is one to ask for.

Lord Howe is reached only by air: QantasLink flies from Sydney daily (about 1 h 50 min), with Brisbane and seasonal Port Macquarie services. Accommodation must be booked before flights (visitor numbers are capped at about 400) and the checked-baggage limit is 14 kg, so most divers hire gear on the island. Dive Lord Howe's shop is at 2 Lagoon Road beside the Lagoon Beach boatsheds; most lodges transfer divers or it is a short bike ride.

Divers board the boat, which is moored in the lagoon, and exit the lagoon through North Passage, then run north-east around North Head to the Admiralty Islets, a group of seven rocky islets a few hundred metres to about 1.5 km off the island's north-east tip. The trip takes about 20 minutes. The boat anchors on sand or a small reef close to the site or runs live if there is current.

Lord Howe sits in the path of the prevailing south-east to east trades and winter westerly fronts. The Admiralty Islets are exposed to north-east and easterly swell and to northerly winds, which blow them out; they come into their own in south-westerly to southerly winds, when the island shelters them and the southern and western sites are rough. A 1.5 m swell from the north-east makes the shallower gutters surgy, and a lump above about 2 m stops the trip.

The Coral Sea current washes these islets more than other sites, so currents can pick up, especially on the outer edges. Visibility is typically 30–40 m. Best months are February–May; winter westerlies are fine here if the swell is down.

The boat anchors on a small reef about 25 m off the north-western corner of the island. Swim west through and around the boulders of the main reef at about 10 m, then head south-east exploring the gutters between the rocky fingers that run out from the island. Turn north for the return, keeping to 10–12 m, and finish back on the anchor reef.

Dive Lord Howe (PADI 5-star, 2 Lagoon Road) – morning double boat dives daily in season, afternoon single dives on demand; site chosen on the day by wind and swell. Howea Divers has also advertised dives here.