Marine Life Society of South Australia Inc.

Newsletter

November 2006   No. 338

“understanding, enjoying & caring for our oceans”

 

Next Meeting

This will be the November General Meeting and will be held at the Conservation Centre, 120 Wakefield Street, Adelaide on Wednesday 15^th November commencing at 7.30pm.

 

Our speaker will be Neville Skinner who will be speaking on Cave Diving.

 

This will be our final General Meeting for the year and there will be no General Meeting in January either owing to the large number of members who will be away on holiday during that month.

 

CONTENTS

The Old Cape Willoughby Light At Kingscote (Steve Reynolds)

The Leeuwin Current And Western Blue Groper (Scoresby Shepherd)

British Marine Life Study Society Report

The Freycinet Trail (Steve Reynolds)

Proposed Leafy Seadragon Aquarium (Robert Browne)

 

Our Christmas picnic/barbecue/dive/social celebration will be at Carrickalinga on Sunday 17^th December. We will meet in the carpark near the toilet block at 10.00am. It would be appreciated if you could let Chris Hall know if you intend to come along. chris.hall@cywhs.sa.gov.au

 

This will be the last Newsletter for 2006. Next month you will receive the 2006 Journal instead.

 

As Editor I would like to thank all those who sent in articles this year for the Newsletter and the Journal as it does make my job much easier.

 

It just remains for me to wish you all a safe and festive Christmas Season.

The Old Cape Willoughby Light At Kingscote

by Steve Reynolds

 

The photo shows John Downing at the opening of the Old Cape Willoughby lighthouse at the Hope Cottage Museum.

Courtesy of John Downing

 

The Cape Willoughby Lighthouse on Kangaroo Island celebrated its 150^th anniversary in January 2002. The actual building of the lighthouse began in 1851. In August that year, Sir Henry Young, the South Australian Governor, whilst opening the new Legislative Council, referred to the building of the lighthouse. Sir Henry said at the time that it was the first lighthouse to be built in the province. (It was also the 17^th lighthouse to be built in Australia.) He also named it the Sturt Light after the explorer Captain Charles Sturt (1795-1869). (It has also been referred to as the Sturt Tower and/or Sturt Lighthouse.)

The present day Cape Willoughby lighthouse.

Photo by Philip Hall

 

Captain Charles Sturt was appointed Registrar General and Treasurer (and Colonial Secretary?) in Adelaide in 1846. As Colonial Secretary, he “raised money from shipping and insurance interests to safeguard the dangerous transit of Backstairs Passage with a lighthouse, for the increasing use of the approaches to Adelaide from the east”. These private funds enabled the impressively sited tower to be built of local materials, together with three timber-framed houses constructed in the small bay to the north. The Sturt Light’s tower was built in a (then) very inaccessible position. It was constructed with basically crude, ready to hand materials - i.e. undressed limestone and granite in lime mortar. The granite and limestone was quarried from a nearby crevice.

 

View from the top of the present lighthouse of the quarry site.

Photo by Philip Hall

 

A strong wooden staircase inside the tower used the walls as their support. Under pressure from locals, via Parliament, the wooden staircase was replaced by a lightweight steel staircase assembly, which, in a reversal of the original concept, helped to support the 26m high walls. A light fibreglass canopy housed the light itself, which was a simple reflector lantern. The overall height of the lighthouse tower was some 27-28m. It started operating in January 1852 (10^th or 16^th?). It was officially opened on 10^th January but it has been said that it first shone on 16^th January. About 1902, the light from the Tiparra Reef (off of Port Hughes & Moonta Bay) in Spencer Gulf was installed in the lighthouse, replacing the original reflector lantern. The top section then weighed some 7 tonnes. The mechanism for the new light had been designed and built by Chance Brothers of Birmingham, England in 1872. The lens assembly would rotate effortlessly in a bath of mercury. An incandescent mantle fuelled by kerosene and hand pumped air provided the 1205 candlepower light. A mechanism provided the power to maintain rotation of the light. The pull of a heavy weight on a cable turned a series of gears at a steady rate. The weight was required to be re-wound periodically by the lightkeeper. This second light was itself removed from the lighthouse in 1974 when the lighthouse was to become fully automated.

 

A lens assembly stored in a shed on site.

Photo by Philip Hall

 

John Downing tells me that demolition work on the old lighthouse had begun in 1972. He says that the old masonry was showing the strain of supporting the great weight of the cast iron mechanism at its head. The old tower was condemned, as the 7 tonne weight of the top section was too heavy. John Downing was the Chairman of the recently formed Kangaroo Island branch of the National Trust of South Australia at the time. The branch acquired the parts of the light for re-erection on a symbolic tower. John had developed Hope Cottage, the National Trust Museum at the top of Centenary Avenue at Kingscote. He says that, upon realising that the lighthouse was already partly demolished, with pieces of machinery and glass scattered in the nearby paddock, the Kangaroo Island Branch of the National Trust, approached the owners, the Commonwealth Lighthouse Service, and managed to ‘do a deal’ (an understatement). He arranged for the re-erection of the light in the grounds of Hope Cottage. Two Council trucks transported the 7-tonne lantern house (4m copper dome?) and mechanism along some 80km of dirt roads from Cape Willoughby to Kingscote. The prisms of glass were also painstakingly transported and re-assembled. John Downing had a team of volunteers who became known as “Dad’s Army”. John himself became affectionately known as Captain Mainwaring of Dad’s Army fame. The volunteers had to somehow assemble the heavy machinery and a masonry tower without any detailed plans or expertise. There was little money available and the workers were largely unskilled. The Council helped by laying the very substantial foundations required. The tower had to be made of round and convexly tapered double walls. No local bricklayer wanted to do the work so Bill Budarick*, an unemployed truck driver, did the job.

*A Heritage Grant of $6,000 went towards Bill Budarick’s wages, the cost of making the outside visitor’s gallery (made in Adelaide) and for the replacement of other steel work.

Bill built a tower 16.5 feet high using a specially devised rotating trammel. He laid bricks against the trammel, which showed where each brick should be placed to form the double wall intended (to a specific design). The tower grew brick by brick from the ground up, with an inner and outer brick wall. This double wall was progressively filled with concrete for reinforcement. The round brick tower and concrete walls had a convex outer face. Jack Elsegood, a retired farmer, smoothly plastered the brickwork with cement render. Johnny Edwards, the Council’s mechanic, expertly welded much of the structural parts together. Johnny welded the central pillar within the tower. This pillar was salvaged from a damaged wharf pile. The floor joists were rigid steel joists (RSJs) from salvaged telephone poles. RSJs are a structural steel girder of "H" section, mainly used as joists, but used locally as telephone poles. The first level flooring of 8mm steel sheet was a recycled truck tray. The lens assembly consists of 596 curved prisms and 16 bullseye lenses approximately 5’ across and 7’ high. The lens assembly rotates once per minute on a frictionless bearing of liquid mercury. An Adelaide firm made a steel viewing-platform and Pilkington Glass donated all of the glass required. The original tinted glass and clear heavy plate glass had been destroyed during demolition.

View over Backstairs Passage from the lighthouse site.

Photo by Philip Hall

 

The 30 feet (10m) overall height of the tower was determined by the maximum lift of the only crane that was available on the island at the time, one provided by the Electricity Trust of SA. The tower was all finished by 1975. A large crowd attended the opening of the lighthouse that year. The Kangaroo Island branch of the National Trust of South Australia (Dad’s Army) received an award from the National Trust for their work. John Downing himself received a Medal of the Order of Australia (OAM) in the Queen’s Birthday Honours for 2004 at the age of 82 for his lifetime of community work on Kangaroo Island. John says that the original Cape Willoughby lighthouse tower was restored rather than replaced by a short concrete structure similar to the one at Cape Jervis. After the 7 tonne burden of the previous light, the top floor had to be replaced with a modern lightweight assembly. The automated mechanism intended for the concrete structure is now fitted at the crest of the old tower in a lightweight fibreglass housing. This means that the lighthouse was still able to celebrate its 150^th anniversary in January 2002. There is a connection between John Downing and our Society. Society member Phyll Bartram is John’s daughter! My thanks go to Phyll Bartram and John Downing and his wife Merle for their considerable assistance with the above details.

 

References:

“Cape Willoughby Lighthouse” by John Downing (an excerpt from “Kangaroo Island: The First 200 Years” Installment 9 by Neville Cordes) 

“The story of “The Old Cape Willoughby Light”, National Trust of South Australia Kangaroo Island Branch (available from Hope Cottage).

“South Australia – What’s in a Name?” by Rodney Cockburn, Axiom Publishing, 2002. ISBN 0 9592519 1 X.

“Great Australian Explorers” by Marcia McEwan, Bay Books, 1985. ISBN 0 85835 864 6.

“Old Jetties Associated With Lighthouses” Part 1, by Steve Reynolds, MLSSA Newsletter, June 2006, No.333.

“The Cruel Sea”, Newspapers in Education series, Part two – Lighthouses of the SA coast, The Advertiser, 27^th September 2005.

“See the light”, an Advertiser Travel SA feature, The Advertiser “Review”.

“The Lighthouse That Moved” by John Downing.

Other papers and correspondence from Phyll Bartram, including notes for her father’s OAM (summarized by her sister Kate).

 

The Leeuwin Current and Western Blue Groper

by Scoresby Shepherd

 

The Leeuwin Current has been known about for some 30 years or so. It is a strongly flowing current that flows down the west Australian coast, and rounds the corner into the Bight, where it flows toward the east. It is a warm winter current and essentially is a hot water bottle warming our coastline. Importantly, it transports larvae of many marine animals, notable the herring (tommy rough) and Australian salmon into SA waters. Once the current arrives off our coast, it’s called (by some) the South Australia current, and when it gets to the west coast of Tasmania, they call it the Zeehan current. But what’s the connection with blue groper?

It turns out that the groper produces larvae with a larval life of some weeks to months. The groper spawns in winter, so we infer that the larvae are caught up in the Leeuwin current and carried toward the east. Analysis of all our groper surveys, (which now number >120) from Esperance thro to the South East of SA shows, interestingly, a linear decline in abundance of juveniles (those < 20 cm). Similarly sub-adults follow a similar decline. So we guess that what is happening is that groper larvae from spawning adults in the eastern Bight are carried easterly and populate our shores with small groper. But the effect dies off as we go further east.

But another interesting thing that has come out of the study is that there seems to be a strong effect of shore fishing on the numbers of sub-adults. How do we know this?

A study of the blue-throated wrasse (a site-attached species) has shown that under strong fishing pressure the average size of fish goes down. Nothing really surprising about that, you say. No, but it means that we can use the average size of wrasse in our Reef Watch fish surveys as an estimate of fishing intensity. This is really useful, because when we look at the size of groper we find that at sites where fishing intensity is high, the size of sub-adult groper also goes down. And this happens right throughout southern Yorke and Fleurieu Peninsulas. So what I think is happening is that rock fishers must be incidentally taking small groper, wherever they fish along the coast. Maybe they don’t recognise them as a protected species. And this no doubt contributes to the decline in numbers of groper that our surveys have shown. Our next task is to see if this is true for other species as well, because I suspect that shore fishing has a very substantial impact on many coastal reef species.

Juvenile Western Blue Groper.

Photo by David Muirhead

 

 

A report from the British Marine Life Study Society’s “Torpedo” magazine,  September 2006 edition.

British Marine Life Study Society http://www.glaucus.org.uk/

 

23 September 2006

 

We dived in Brighton Marina in the same area (near the entrance) that the adult Short-snouted Seahorse, Hippocampus hippocampus, was discovered in June, and over a period of a few hours we spotted about a dozen juvenile Seahorses ranging in size from 10 to 25 mm. They were not all found together. This looks as if there is a population breeding in the marina. 

 

Report by Dr Gerald Legg (Booth Museum)  

 

Seahorse in Brighton Marina
    Photograph by
Michelle Legg

 

The Freycinet Trail

by Steve Reynolds

 

An interpretive trail consisting of fifteen interpretive signs has been established near Whyalla. The trail runs along the shore at Fitzgerald Bay on the Eyre Peninsula. It is named the Freycinet Trail after Louis-Claude de Freycinet who explored the area during Nicolas Baudin’s expedition in 1803. The fifteen interpretive signs cover topics such as: -

The Australian Defence training area at Cultana

Aboriginal tribes of the area

The only tidal creek between Port Augusta and Whyalla

A geological ridge formed about 30,000 years ago

The aquaculture industry in Fitzgerald Bay

The diversity of marine life in the area

The local seafood industry on the Eyre Peninsula

Australian Giant Cuttlefish, Sepia apama

The marine environment of Spencer Gulf

The Point Lowly Lighthouse

The Port Bonython jetty

European exploration

Plants and animals

Mangroves

Life between the tides

The trail starts at the deepest point of Fitzgerald Bay, on the scenic drive between Backy Point and Point Lowly. It runs east along the shore of the bay to the other (southern) side of Point Lowly at False Bay. Several of the signs feature underwater photos taken by Ron Hardman. If you are able to visit Whyalla, take the time to check out the Freycinet Trail.

 

Point Lowly Lighthouse.

Photo by Philip Hall

 

Proposed Leafy Seadragon Aquarium

by Dr Robert Browne,  MLSSA Science Officer

 

Don Chapman, Event Management/Tourism Officer, Yankalilla, Visitor Information Centre, sent MLSSA an email asking for comments on a proposed aquarium dedicated to the Leafy Seadragon.

 

Don asked ‘Could the aquarium itself offer an opportunity for you or your members if it had a genuine research capability?’. The ‘Leafy’ was named in 1865 by Gunther, and was  protected earlier in South Australia than its immediate relatives in the syngnathids, the seahorses and pipefish. Other syngnathids were only fully protected in South Australia in 2006. The Leafy Seadragon (Phycodurus eques) has become symbolic of marine conservation and – along with the Giant Cuttlefish (Sepia apama) – of marine ecotourism in South Australia. Because of its conservation status the ‘Leafy’ as it is affectionately called must be a model for best practice in management and research.   

 

Along with questions about the Aquarium there was also a proposal for the formation of a foundation dedicated to Leafy Seadragon conservation. The proposed foundation will strongly support the Aquarium and also diving at Rapid Bay Jetty, a top Leafy Seadragon dive spot where among the piles of the jetty a diver is almost assured of sighting a ‘Leafy’. The old Rapid Bay Jetty is unsafe and has been closed. This means a long swim out for divers, and also the lack of a facility close to diving sites for emergency treatment as a consequence of a diving accident. The Rapid Bay jetty diving site is regarded as significant to tourism in South Australia. To assist marine ecotourism a new jetty parallel to the old jetty is planned at a cost of about $2,000,000.

 

The Leafy Seadragon belongs to the syngnathids which also include the Weedy Seadragon, Pipefish, and Seahorses. The syngnathids are one of the most interesting and little known groups of inshore fish and are of great conservation significance. The significance of syngnathids to conservation was recognized through their blanket protection in South Australia. 

 

For more information the ‘Inshore Fish Group’ site which is supported by MLSSA, www.ifg.bioteck.org  has species profiles for South Australian syngnathids. So, in a nutshell, any facility that can offer a genuine research capability for the study of the Leafy Seadragon, or any other syngnathid, would be invaluable. To a conservation biologist a ‘genuine research capability’ means the provision of a facility in which research of value to Leafy Seadragon conservation can be conducted. The standard for ‘research of value’ is a quality acceptable to peer reviewed scientific journals.

 

The possible types of research will be determined by the design of the system. The best type of research for a cluster of medium to small display aquariums is of behaviors including courtship rituals, mating, reproduction, and territoriality. In particular, behaviors involved with courtship and reproduction offer a great opportunity for educational displays. 

 

I have recently seen two great conservation exhibits in the USA at the Chattanooga and New Orleans Aquariums which were dedicated to syngnathids and marine conservation. These were very popular with the public. The candidates for the Leafy Seadragon research projects should be familiar with Syngnathid biology, and the research should have institutional ethics approval. Preferably conservation research should be non-invasive. 

 

Other research opportunities for both marine conservation and eco-tourism present themselves at Rapid Bay.  The anticipated increase in recreational diving at Rapid Bay should encourage the establishment of more habitats for the Leafy Seadragon. Besides research in the proposed Aquarium other research could investigate different options for the creation of more habitat for Leafy Seadragons, and other marine fauna and flora in the area. These projects could be in conjunction with improved quality of habitat for divers. The potential at Rapid Bay for temperate water marine eco-tourism is great. It is clear that if a community can integrate economic and cultural goals with conservation this is the best possible outcome. Marine eco-tourism at Yankalilla and Rapid Bay means a greater public awareness of South Australia’s beautiful and unique inshore ecosystems and their conservation value. The proposed Leafy Seadragon Aquarium if dedicated to conservation and properly conducted research would be an invaluable asset within this conservation strategy.