This is the MLSSA Newsletter, the monthly publication of the Marine Life Society Of South Australia Inc. Our Society is active in trying to protect our marine environment and this Newsletter usually contains articles about marine life and the marine environment.
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The October General Meeting will be
held at our usual meeting place, the Conservation Centre, 120 Wakefield
Street. We will begin at 8pm with the business part of the night and then,
after the break, we will be entranced by a selection of David Muirhead's
latest underwater slides. Some of these will no doubt be selected for the
Photo Index. The Committee has had the privilege of a quick preview at
the September Committee Meeting and we can guarantee the quality is again
outstanding!
Congratulations Phill and Helpers on another great result, viz:
1st Best Planted
1st Marine Fish
1st Best Marine Aquarium
Champion Marine Aquarium
We crouch at the cliff's edge surveying the dive site. One hundred metres below, the ocean sparkles invitingly and the almost imperceptible swell moves slowly over shadowy patches of submerged reef. Sweating in full gear in the late morning sun, we descend the steep ridge that is our only access to the beach. Elsewhere cliffs meet the Southern Ocean abruptly and one can look directly over the edge into the depths of "The Gap" which is actually a square notch in the otherwise largely regular line of the limestone cliffs. Although the diving here at the foot of the Yorke peninsula can be excellent, on most days a shore entry is made hazardous by the prevailing southerly winds and boats launched from the nearest ramp at Edithburgh face a long journey along the exposed coast. Soon the north-west wind at our backs is gone and we are in a sheltered amphitheater with the gull's cries loud in the stillness. After struggling through the coarse soft sand to the point nearest "The Gap" we are exhausted, but not too exhausted to miss the fact that the swells look much bigger at eye level! But today's conditions are the best we're likely to see here, so we don fins, flounder into the dumpers, snorkel out to the first rocky point to the left and dive to the cliff base. The sandy bottom at 5metres displays only dead seagrass drifting amongst a few weed-tousled rocks - very disappointing after the view from the cliff top. And as if this were not enough, it seems the not-so-famous S.A. visibility has let us down, being barely three metres, but we discover after swimming further that this is due to the swell channelling the disintegrating weed past the point towards the beach. Moving along the cliff base we soon encounter 10 metre viz and deep water, down to 25 metres at "The Gap" itself, and here the dive really begins.
There are jagged limestone outcrops richly clothed in kelp and other brown algae, which moves to and fro revealing glimpses of colourful overhangs, and the fish life can only be described as prolific. Blue Devils display their finery fleetingly before returning to their dark lairs, numerous dusky morwong approach in disarmingly trusting fashion, suicidal curiosity being a hallmark of this species, and ghostly schools of swallowtail divide before us. Looking up we see sweep and ruffs circling in our bubbles against the sunlit surface. Numerous rockfish patrol the bottom including sedate old wives and magpie perch, aggressive scalyfin, leatherjackets snake-like herring cale and various energetic wrasse. Indeed, of all the fish groups, the wrasse best characterise S.A. diving, being ubiquitous in our coastal waters. But enjoying the wrasse family underwater and catching them on film are two different things for they seldom interrupt their busy schedule to pose for the camera and when they do they often park theselves in amongst thick weed. Nevertheless these fish deserve the photographer's attention and certainly a Senator Wrasse in full finery can rival many of his tropical cousins.
Fish aside, probably the most striking features of "The Gap" are the massive slabs of limestone overhang which have dropped from the cliff to the seabed. As well as adding dimension to the sea floor, some of these lie at angles against the base of the cliff, so that a diver can swim through naturally formed tunnels amongst schools of bullseye, admire the encrusting ascidians, sponges and bryzoans and feel transiently free from those mental images of great white sharks appearing suddenly on the scene! The slabs conjure the image of an overgrown demolition site but the fish know better - to them they're more like nuclear shelters, fending off the powerful swells of the open ocean.
Wedged in the base of one slab, a lobster's antennae betray his presence, a timely reminder that the sea holds more for some divers than beauty and solace. At 20 metres plus depth our air doesn't allow more through exploration so, reluctantly, we head back, already resolving to return. But the dive is not yet over.
As we're approaching the last point before the beach a dark form comes barrelling towards us, spade-like pectoral fins flapping lazily, only to veer off at the last moment. It's the mother of all Blue Groper (actually members of the wrasse family) and these are the largest scaled fish a diver is likely to encounter. We watch rapt, as she comes and goes several times, and is joined by half a dozen smaller "blueys", some not yet having attained the mature fish's deep blue finish (juveniles are dull green) and looking clearly inferior as a consequence.
But now the dive is over. Trudging up the beach we slump onto the sand and savour again the sounds and smells of this lonely shore. Pulling back our hoods, the freshening breeze seems loud in our ears and as we view the white caps appearing out to sea, we realise sadly that it could be quite some time before we again have the privilege of being amongst the creatures of "The Gap".
Jonathon Walsh suggested at our AGM that this should become our name following our communications with people in England and America. We had received an e-mail from the Marine Conservation Society (UK) suggesting that our web site be linked with theirs. We have agreed to this link with them and will extend them the same courtesy by linking their site to ours. They may decide to use articles of interest in our Newsletters and Journals from our web site. The MCS's Marine Conservation magazine will not now be sent to us any more since it can be accessed through their web site. The address for the site is:- www.mcsuk.mcmail.com
We had also received some e-mails from a William B. Henry in America. It seems that William lives in Pennsylvania and works in New Jersey. He has a friend in New Jersey who had had passed on a Leafy Seadragon drawing that he had received from a South Australian. I had apparently sent the drawing to the SA man some time ago and it has now gone half way around the world. William was inspired by the drawing and wants to do a woodcarving of a Leafy. He requested all kinds of information about the Leafy to help with his project. We advised William of a number of contacts who could be helpful to him. We also told him about our web site which features Leafy photos in our Index. William has now copied the pictures and has also requested a video tape from Tony Isaacson. He is a certified scuba diver and may maintain contact with us.
The Internet is certainly creating new contacts around the world and our web site is a handy reference for these new contacts to focus on. MLSSA International? Perhaps, but we may have to drop the SA bit!
In the 18th century sailing ships were categorised by their hull shape. In the 19th century they were then categorised by their rig. A 19th century barque was a ship with three to five masts, fore and aft rigged on the after mast, and square-rigged on all of the others. (A "Bark" was an 18th century sailing ship categorised by its hull, although my dictionary suggests that "barques" & "barks" are the same thing. A "Barquentine" is something different again. It is a 19th century sailing ship with different rig to a Barque.)
Steve Reynolds
At our April Committee Meeting David Muirhead told us about his recent trip to Kangaroo Island where he dived on two of the many shipwrecks there. They were the "Fides" and "Portland Maru". The "Fides" was a wooden barque which sank near Snug Cove in 1860. The "Portland Maru" was a huge ship which sank at Cape Torrens in 1935.
FIDES
The "Fides" was built in Finland in 1857. It was carrying general cargo from London to Adelaide when it drifted onto rocks near Cape Borda. There were 15 seamen on board but only about five of them reached shore whilst the ship broke up on the rocks. An article in one of the newsletters from the old Reservoir & Paradise Dive Club described the wreck and said that the exact date of sinking was 22nd May (but as 1876 instead of 1860). The article also stated that six (not 5) of the crew of fifteen made it to shore and that the barque weighed 387 tons. (Ships were not weighed to find their "tonnage". Tonnage has always been determined by a system of measurements which I will describe in another article. Some newspaper articles give the tonnage of the "Fides" as tonnes instead of tons but a tonne is about 98% of a ton. The Reservoir & Paradise article says that the "Fides" is now "little more than a couple of large conglomerates lying in a rocky crevice underneath the wave-swept cliffs between Snug Cove and Kangaroo Beach. She is located just east of a pronounced sea cave at water level . . She lies in very shallow water and surge action is pronounced in the crevice on even the calmest of seas. The crevice runs roughly North-South into the cliffs." The article then describes access to the wreck and the kind of artefacts that divers may find on the wreck.
PORTLAND MARU
The "Portland Maru" sprang a leak near Cape du Couedec and began sinking bow first. She reached Cape Torrens before finally resting in 15m of water. No lives were lost. Said to be one of the best recreational dives in SA, it now lies 200m from the pebble beach at Cape Torrens. We have a pamphlet in our Society library published by the Department of Environment & Land Management about SA shipwrecks. It is titled "Kangaroo Island maritime heritage trail" and describes the "Portland Maru" in detail. It says that the ship was built in Japan in 1919. Her length was over 380 feet and she had a gross tonnage of 5865 tons. The pamphlet describes the visual impact of the wreck as spectacular. It says that the engine and boilers of the wreck are still standing upright. They are said to be over 6m from top to bottom, covered with algae, sponges and crustaceans and surrounded by a wide variety of fish.
Steve Reynolds
I thought I would give you a bit of an update on damage caused by the last storm that passed through the Central Yorke Peninsula area on the 26th, 27th and 28th of August 1998.
Early on Wednesday morning the 29th of August, I had a call from Stuart Moody. The reason for the call was to head off to Waraulty Beach which is located approximately 15 kilometres south of Port Victoria, to see if any bottles had been washed in from ships that had been sunk in the past off Wardang Island.
The seaweed washed up on the beach was the first thing that greeted us as we drove up and over the sand hills, the beach was just littered with it as far as the eye could see. Up until now these beaches had been clear of seaweed, but since Easter the prawn trawlers had been giving the area a good going over and may be responsible for ripping up the seagrass beds as they possibly did in St Vincent Gulf in past years.
We drove far down the beach and when the sand became a little soft decided to hop out of the vehicle and walk along the beach. Although we did not find any old bottles, there was plenty of man made rubbish washed up, such as rope from fishing boats, bits of netting and general rubbish such as plastic bottles, bags and bits of rag. We also found a used Crows cap which Stuart claimed.
Sea creatures which were casualties of the storm and were washed up comprised several different species of fish, such as Bullseyes, Blue Devils and a large number of big Cuttlefish. I would say the length of these started at around a good 90 centimetres and could weigh several kilo's. There were also a large number of cuttlefish backbone visible.
We also came across a young seal pup which I would say could have been washed off Goose Island, and because of the severity of the storm perished in the turbulent waters of the last few days. There were no physical signs of bite marks on the carcass.
So as you can see it is not only human tragedy that comes from rough seas, but also that of its residents.
Ron Bellchambers
Since publishing the article on this subject in the September '98 Newsletter quite an amount of information has emerged.
Many people have operated this type of filter very successfully for several years. These people have mainly used it to run tropical reef type aquaria with limited numbers of fish.
It has been found that the plenum (water space under the filter) experiences a buildup of nutrients. At the same time both the pH and the oxygen levels steadily fall and this combination produces a potentially unsafe area within the aquarium. While it is separated from the main water body by the filter bed it is reasonably safe.
These nutrients, however, can leach back into the main part of the tank by osmosis and cause "unexplained" problems and algal outbreaks after a period of time. Should a crab or other burrower then breach the upper mesh layer (see last months article diagram) a sudden release of nutrients could result in the death of many creatures in the aquarium.
One solution to this problem has been the use of a syphon to remove, on a regular basis, some of the "dead" water in the plenum. If this is regularly carried out then the buildup of nutrients will be reduced. By leaving one of the existing corner uplifts in place when setting up, a suction tube can be inserted without disturbing the filter.
Most of the people who use this system make great use of various test kits. This greatly adds to the cost of running the tank and the amount of work involved. After the result of each test chemicals may need to be added to "normalise" the water.
The uplift system we presently use means that an air pump is the main supply of air and water movement. In the live sand setup there must be a strong water movement and so at least one pump must be installed in the tank.
Philip Hall
Seasearch is a project for amateur divers. It was launched in 1986, and is now managed jointly by the Marine Conservation Society (MCS) and the Marine Nature Conservation Review (MNCR). Its aim is to collect information on the seabed around the coast of Britain.
Surprisingly little is known about our marine heritage in terms of its scenery or what lives where. Seasearch is trying to redress this. And divers, of course, are in the best possible position to be able to note exactly what is below the sea. The information collected through this diving helps to map the seabed. The least it can do is to confirm that existing information (sometimes collected through less intensive methods - such as towed video systems) is accurate. At best it can reveal creatures or habitats previously unknown within an area.
While the results of Seasearches are seldom spectacular, they do reveal the extent of creatures' geographical ranges. In good summers, like 1995, these can extend quite markedly. Occasionally, unusual events or creatures are seen - massed heart urchins for example, or odd fish such as tadpole fish, red mullet, and even trigger fish. The information produced by 'Seasearching' is used to help scientists locate sites to study.
All that is required of Seasearch volunteers is to be prepared to make observations of underwater habitats and the life that these support. No marine biological expertise is necessary. A starter pack explains what information needs to be collected and recorded, and contains the forms which need to be completed after a dive.
Carrying out a detailed Seasearch is a very good way of learning about the undersea world. It can also be very rewarding. Looking carefully at a small part of the seabed often reveals creatures which divers would more usually fin past. Some Seasearches are organised or attended by professional marine biologists, and are an excellent way of finding out what some of the more perplexing creatures are.
Diving skills can be enhanced. These projects have excellent training potential. Marshalling a big Seasearch is a real challenge. Patience and planning are required when dealing with a variety of divers and boats from other clubs and areas. Navigation skills can be developed, as can boathandling and dive leading. Photography and marine life identification can always be improved.
Pilot Seasearches, building on work carried out by the MCS, were first carried out in 1986. Starter packs are currently available at no cost from:
Lucy Gilkes, The Countryside Council for Wales, Plas Penrhos, Ffordd Penrhos, Bangor, Gwynedd LL57 2LQ.
Dr David Donnan, Scottish Natural Heritage, 2-5 Anderson Place, Edinburgh EH6 5NP.
Dr Alexander Downeyat, English Nature, Northminster House, Peterborough PE1 1UA.
Overall Seasearch co-ordination: Dr Bob Foster-Smith, Department of Marine Science, Ridley Building, University of Newcastle, Newcastle upon Tyne NE1 7RU.
Adapted from an article which appeared in DIVER - June 1996
by Paul Kay
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