Montague Island

Everything starts at Narooma. Boats run out from the inlet and have to cross the entrance bar to reach open water, which is the single thing most likely to cancel a trip, since swell can shut the bar on a morning that looks fine from the beach. The crossing to the island is short but exposed, and often lumpy. Once out there, a standard trip is two dives: the colony first, then a reef or a gutter on whichever side of the island the wind has left alone.

The island is granite, and underwater that means clean boulder slopes, kelp over the shallow tops and channels cut through the rock where water pushes between. Nothing goes much past 25 m, so the limiting factor is cold rather than depth. The seal dive itself is shallow and unstructured: you stay near the shelf, keep your hands to yourself and let the animals set the distance, which they will do repeatedly and at speed. On the outer sides the current picks up and dives become short drifts along the rock.

It suits divers who are there for an animal encounter more than for a dive site; the topography is pleasant rather than the point. What it does ask for is tolerance of an exposed boat ride and water between 14°C and 22°C. May through September rate highest, with the colony still busy into October, and those are also the months when the ride out is least comfortable. Summer is warmer and generally clearer with a quieter haul-out, so pick the season for what you want from it. The island is a nature reserve, so any landing happens on a separate guided walk rather than as part of the dive day.