Hugo's Trench

You drop into the trench and settle between two sheer walls, with a working range of 15 to 18 m from the top of the rock to the bottom of the cut. There are in fact two parallel gutters here, Hugo's Trench and False Trench, both on the sheltered side of the island and both out of the strong northerlies that run from September to Christmas. The dive is linear — you follow the gutter rather than picking a route — which makes it an easy site to rush.

Pace is the whole thing here, because most of what lives on these faces only shows itself once you have stopped moving and let your eyes settle on one patch of rock. Nudibranchs are the constant, Spanish dancers among them; crayfish and mantis shrimp sit back in the holes, moray eels use the same cracks, and ghostfish, pineapple fish and bubble snails turn up on the faces once you are looking at the right scale. None of it is large, and none of it is obvious at swimming speed.

The trench is not only macro. Bull rays and wobbegongs use the crevices here as well, and both are large enough to be easy to miss when you are focused on something thumb-sized — wobbegongs in particular lie flat and patterned against the rock, so watch where you put hands and fins. With a maximum of 18 m, depth is not what makes this dive; the rock close on both sides is.