Dive Number: 9 28/02/2010 15.54 Steeles Rocks, Portarlington
Wind: 15-20knot southerlies
Tide: 0.82 high tide at geelong
Conditions: A windy and overcast day, but portarlington being protected from southerlies meant only surface chop, but generally pretty good.
Bottom Type: Rocky Rubble covered in a layer of mud and silt.
Visibilty: 3-5m
Water Temp: 21c
Bottom Time: 107 minutes
Max Depth: 4.2m
Air usage: 165bar/2400psi
SAC: 13.2 litres/min
Details: A dive lesson in overexertion. I swam about 1km from the boatramp towards the peir at a liesurely pace. But decided to vline it back to the boatramp on return, and when surfacing to check my orientation, started to feel a bit dizzy and panicy. An experienced diver died here a couple of months ago and i consider this a vital lesson learnt early. Steeles Rocks is a pretty vast underwater reef system extending about 4km from the pier in the west to well past the boatramp in the east. Its ecology would be considered “the barrens” for the most part, being generally damaged by silt build up on the rocks. This means theres not a lot of marine life to be seen, and its tempting to cover large distances searching and exploring the area. I definently overexerted myself covering this distance, and i think the oxygen demanded by the bodies muscles reduces the oxygen supply to the brain, which can lead to lightheadedness, and potentially blackout. I feel wiser for this experience.
Camera Details: Canon 17-40mm, single SS200 strobe.
Dive Report: Steeles Rocks could be an amazing place if it was allowed to recover, with some great rocky rubble sections and reef systems with small legdes and overhangs. Unfortunatley a muddy silt covers most of the rock restricting algea and sponge growth. There are still some nice patches around though, with orange sponges and these grey sponge/ascidian formations. Its also got the largest concentration of hard coral that i’ve seen in the bay.
Most of the larger fish species, such as moonlighters and old wives, are very flighty here, due to the area being overused by spearfishers.
So to find good critters at Steeles rocks, you have to check whats under the rocks.
I found this strange green worm which moved by pulsating spherical muscles through its body. UPDATE: This is Metabonellia haswelli.
I didn’t see a lot else of interest , a couple of smooty rays in the sand and under ledges, and a large school of salmon that circled me.