Diving in Rivers and Estuaries - July 06
When I heard about our chosen dive site I was reminded about the time I dived the Swan River in WA and didn’t take my camera as I thought there would be nothing much to photograph…………how wrong I was! With anemones as big as tea plates and the most gorgeous green-lined paper bubble I could have kicked myself…very hard! I watched this amazing bubble like creature undulate its way across the sand with its apricot coloured foot that spread out like a ball gown and flowed around the beautiful shell that sat atop this mollusc; never more have I regretted not having a camera as I watched this lovely creature easily lit by the suns rays in 5metres on my three minute stop, what a missed opportunity!. Sadly I never saw another of these during my time in Australia. However, this occasion was to be quite different. Armed with my usual camera I was looking forward to this dive because I knew from what others had said that the amount of marine life in the East Narrows, (which was the area of Falmouth estuary that we were diving) was considerable.
The estuary bottoms out at around 30-35m but I had no intention of going that deep as I knew that there was plenty of life at a shallower depth and I would get a longer dive that would enable me to get more of a feel for the area. In addition we had been warned that a large ship, presently moored a little further up, would be moving in about an hours time so the skipper wanted us out of the main estuary thoroughfare and in the shallows by then. It was to be a drift dive and I was just hoping it wouldn’t be to fast on the incoming tide which would drag me away from things I wanted to photograph which was always so irritating. Descending to about 20m I was surprised at the visibility, which was around 5-6m. Looking around I could make out various pieces of debris and rubbish that had been thrown out of boats. I know this is a good spot for ‘spidge’ as many US ships used this thoroughfare during the war. Not being as ‘environmentally aware’ as we are today, much was thrown overboard without a second thought.
The bottom was covered with little patches of what I thought were green and red weed but I was most surprised when some of these started to move. They were in fact spider crabs and I have never seen them so well disguised to look exactly like the little patches of weed that covered the seabed. I was swimming very close to the bottom and I think occasionally my knee would brush the top of them and they would suddenly lurch forward in front of me. It was only when they were up on their orangey red spidery legs that they were visible.
Many other tiny little decorator crabs were dotted around sitting a top the clumps of weed. My camera seemed to have a lot of trouble focusing on them for some reason.
Various anemones and worms were scattered all over the sand. As I gradually moved up to the shallower levels although there was less life there were still a fair few things dotted around going about their business amid the pink merle that covered the seabed. It is calcified red seaweed and the effect reminded me of pink heather on mountains as it more or less covered everything and gave the whole scene a pink tinge. There were quite a lot of large hermit crabs that were difficult to see but once disturbed trundled their way round the patches of merle. With red weedy bits, or in some cases anemones living on their backs it really made them part of the scenery and therefore hard to spot.
Deciding it was time to head up and being at 8m I decided to move further up the bank so that I could cruise along looking at stuff whilst doing my stop. Unfortunately I couldn’t find anything shallower than 8.1. Later I was to learn I was not the only one with this idea nor to find that it didn’t seem to get any shallower. Deciding that I would have to just go and hang somewhere for my three minute stop and think chilled out thoughts instead of looking at cool stuff and I was just about to let off my DSMB when I noticed a thornback ray laying stock still on the bottom…….. well…….I really couldn’t miss this opportunity could I! Knowing that I shouldn’t dally too long I quickly shot off a few pictures. It’s at times like these you realise how slowly your strobe recycles!
I hope I get to dive this again as it was so fruitful in terms of marine life. Again probably a very underrated dive but when the viz is good, as it was on this particular occasion, its a brilliant dive. Never again shall I underestimate rivers or estuary in terms of what I might see. I think the dive in The Swan River and the missed opportunities for some great pictures taught me that.
August 1st, 2006 at 11:26 am
Nice report Jane, enjoyed reading it.