Anemone Lump is widely regarded as the Abrolhos's premier dive site. It is a coral bommie in the Easter Group rising from about 38-40 m to within 3-8 m of the surface. Marine Life Network describes its covering of anemones with resident anemonefish and thousands of silvery minnows (baitfish) swirling around the lump, with tiger sharks recorded; Eco Abrolhos adds huge plate corals and large, curious spangled emperor and snapper.

The bommie concentrates life in the open water around it: schools of baitfish attract predators, and the anemone fields at this latitude – thanks to the Leeuwin Current – are a striking sight. Strong currents sweep the site, which feeds the growth but means it must be dived at slack water, ideally with a guide.

It suits Advanced Open Water divers comfortable with current and depth; snorkellers can enjoy the top in calm, slack conditions. It is a highlight of liveaboard itineraries in the Easter Group, which also include Rolland Passage and the sea lions of Little Sandy Island.

Slack water at the Abrolhos is short, so liveaboard crews time the dive carefully and usually drop divers up-current of the lump. The shallow top also makes an excellent long safety stop among the anemones. Photographers should bring wide-angle for the baitfish clouds and macro for the anemonefish. Nitrox helps extend time on the flanks, and a reef hook is not appropriate on living coral – hold position by finning or using dead rock only.

The Houtman Abrolhos lie 60-80 km west of Geraldton (about 420 km north of Perth). There is no public accommodation or camping on the islands, so divers visit on liveaboard trips departing Geraldton (a 3-5 hour crossing), on private vessels using the public moorings, or – for snorkelling only – on scenic-flight day tours that land on East Wallabi Island. Anemone Lump is in the Easter Group, the central group of the Abrolhos, about 60 km (3-4 hours) from Geraldton.

Liveaboards visit on slack tide; there is no public GPS mark.

The Abrolhos sit on the edge of the continental shelf in the path of the warm Leeuwin Current, which keeps water at 20-24°C and supports the world's southernmost major coral reefs. The islands are exposed to the south-west swell and to strong southerly winds that blow most afternoons from October to March; the crossing from Geraldton is often rough. Marine Life Network recommends March-May and September-November; late summer-autumn highs give the calmest seas.

Western rock lobster season (15 March-30 June) brings fishing camps and boat traffic. Marine Life Network notes the site is affected by strong currents; dive it at slack water and in light winds.

Descend at slack water onto the upper bommie at 8-12 m, circle it looking at the anemone fields and plate corals, drop to 20-25 m on the flanks if the current allows, and return to the top for the safety stop; deploy a DSMB if current picks up.

Liveaboard only for diving: Image Dive – 'Southern Image', the only dedicated dive boat at the Abrolhos (4 days/4 nights from Geraldton, max 8 divers, 3-4 dives a day); Eco Abrolhos Cruises – 5-day small-group cruises from Geraldton with snorkelling and diving; occasional Perth club charters. Batavia Coast Dive & Watersports (Geraldton) runs Abrolhos trips when boats are available. Eco Abrolhos lists Anemone Lump as an outstanding snorkel and dive location.