The south-eastern tip of Kanowna Island is the deep wall of the Anser Group, and Scuba Doctor rates it, with Skull Rock and South East Point, in the Deep/Technical class of Prom dives. The listing describes a wall that plunges steeply to the bottom at 55 metres, with plenty of boulders, caves and swim-throughs to explore, current swept, facing south-east into the often wild seas of Bass Strait. The wall is granite, dropping in sheer faces and stacked blocks from the kelp line to a boulder floor at 55 m, and the gaps between the blocks form caves and swim-throughs at several depths.

Because the site takes the full force of the swell and the tidal stream between the islands and South Point, the growth is the richest kind of exposed-reef cover: dense sponge gardens, yellow zoanthids, gorgonians and sea whips angled into the current, soft corals and jewel anemones, with crayfish deep in the ledges. Fish life is described as prolific – clouds of butterfly and barber perch, sweep, bullseyes in the caves, boarfish and morwong on the ledges, with kingfish and salmon passing in the blue – and the fur seals from the colony on the other side of the island follow divers along the wall. The depth and the current make this a dive for very experienced divers, ideally with nitrox or technical gases and a live boat, and only on a day of complete calm at slack water; it is a site that may see a handful of divers a year.

For those divers it combines everything the southern Prom offers – big walls, big fish life, seals and 25 m visibility – on one corner of one island, with the added interest of caves and swim-throughs that the neighbouring seal sites lack. The seal-colony vessel exclusion zone and marine national park rules apply as for the rest of Kanowna.

Boat only. The nearest launch is the Tidal River beach ramp at the western end of Norman Bay (4WD beach launch, key and deposit from the Parks Victoria office; needs several people and calm surf), from which the western islands are 5–12 km. Larger trailer boats launch at Port Welshpool (sealed ramp, Corner Inlet) and run about 50–60 km around South East Point – 1.5–2 hours – or at Sandy Point (Waratah Bay, beach ramp) and run 35–45 km south-east.

Sites are exposed to Bass Strait and require settled weather, a seaworthy boat, radio, and self-sufficiency: there is no rescue or refuelling closer than Port Welshpool. The south-east tip is the most exposed corner of Kanowna, 12 km from Tidal River; it is a live-boat dive in slack water only, outside the seal-colony exclusion zone (check Parks Victoria for current distances).

Current swept and facing south-east into the often wild seas of Bass Strait; dive only at slack water with calm seas, no swell and no wind. Any southerly or easterly swell makes the tip untenable. This is a rare-day site even by Prom standards; late summer and autumn calms are the only realistic windows.

Drop a shot or descend a live-boat line onto the top of the wall at 10–15 m near the tip, descend the face to a planned maximum (30–40 m recreational; the wall bottoms at 55 m), then work along the wall through the boulders, caves and swim-throughs at a rising depth, turning on a third of gas or NDL. Ascend on an SMB in open water clear of the rock with a deep stop and full safety stop.

Rated Deep/Technical; suits trimix or rebreather divers for the 40–55 m base; recreational divers set a 30–40 m floor and use EAN32.

No dive charter operates at Wilsons Promontory. Sites are dived from club and private trailer boats – Dive La Trobe, VSAG, Melbourne University Underwater Club and Dive Victoria Group run occasional camping-and-diving trips – launching at Tidal River (beach launch, permit/key from Parks Victoria), Port Welshpool or Sandy Point. Wilsons Promontory Cruises (Port Welshpool) runs sightseeing cruises to Skull Rock and the islands but no diving.