Big Reef, Portland

Meet the site

Big Reef lies about 1.2 km south of Point Danger, the headland with the mainland gannet colony that guards the southern side of Portland Bay, and it sits directly on the boat route from the harbour to Lawrence Rocks. The Scuba Doctor observes that it can easily be overlooked on the way to somewhere else, but that it offers a vast array of interesting dive opportunities. The eastern side drops steeply from about 5 m on the reef top to 15 m on the sand, forming a low wall with ledges and undercuts; the western side descends more gradually in a series of ridges and gutters. The reef was once an important commercial abalone ground, which tells you about the habitat – clean rock, heavy algal growth and plenty of crevices – and although the commercial fishing has moved on, the reef still carries the western Victorian community in good numbers: kelp and mixed algae on the tops, sponges and ascidians on the eastern face, crayfish and abalone in the ledges, and blue-throat wrasse, magpie perch, sea sweep, herring cale, zebrafish, leatherjackets and boarfish over and under the structure, with rays on the sand and seals from Lawrence Rocks and Point Danger passing through.

It is an easy Open Water boat dive fifteen minutes from the harbour, with a wall to follow and a reef top to cross, and it makes a sensible first or second dive of a Portland day, a fallback when Lawrence Rocks is too rough, or a shallow finish after the Emily S. The Passage Bommie 160 m to the north and Little Reef nearby extend the same ground. Like everything at Portland it is very weather dependent and needs a low swell and light winds, and since no dive charter operates from the port it is dived from private boats and by arrangement with fishing charters, with Portland SCUBA the local source of air and advice. Victorian bag limits apply to crayfish and abalone.

What you might see

Southern rock lobster, black-lip abalone, blue-throat wrasse, magpie perch, sea sweep, herring cale, zebrafish, leatherjackets, longsnout boarfish, rays, Australian fur seals, kelp, sponges and ascidians on the eastern face

Location

Reef about 1.2 km south of Point Danger, Portland, on the way to Lawrence Rocks, dropping steeply from 5 to 15 m on its eastern side and more gradually on the west.

Facilities nearby

Portland Harbour ramps with trailer parking, toilets and showers at the Lee Breakwater; Portland SCUBA for air, gear and courses; Portland town facilities, fuel and accommodation.