MLSSA

Newsletter

JUNE 2002

No. 289

"Understanding, enjoying & caring for our oceans"


 

Next Meeting

Our next meeting will be held at the Conservation Centre, 120 Wakefield Street on Wednesday 19th June, commencing at 7.30pm.

Our speaker will be Chris Halstead who will discuss Marine Protected Areas.


Contents

The Glenelg Jetty

2002 Annual General Meeting

Old Balls Still Scorch

Christmas Island Film Shown At Our April Meeting

The Distribution of Port Jackson Sharks (& Wobbegongs)

 


MEMBERSHIPS

If you were a member last year then you need to pay your renewal as soon as possible if you wish to stay a member.

A reminder sticker will be attached to this newsletter if you have not been recorded as having paid up to the June Committee Meeting.


The Glenelg Jetty

THE NAME OF GLENELG

Glenelg is named after Lord Glenelg, the Secretary of State for the Colonies. It was he who gazetted the colonisation commissioners for South Australia. The idea of naming the area after him came from Governor Hindmarsh's secretary, George Stevenson.

SECOND JETTY

The jetty presently at Glenelg is the town's second jetty. It was built in 1968 to replace the original jetty which had to be demolished due to storm damage.

ORIGINAL JETTY

Glenelg’s first jetty was built using cast iron screwpiles. Cast-iron sections had been wrought in England and shipped to Glenelg.

THE "BERKSHIRE"

In 1856 the ironwork was being shipped to Glenelg on the freighter "Berkshire" when it ran aground off the coast of Brazil and large sections of ironwork (60 tons) had to be thrown overboard. The "Berkshire" then apparently proceeded to Rio de Janeiro where it landed the remaining ironwork.

ARRIVAL OF IRONWORK

Somehow sufficient ironwork was eventually delivered to Glenelg but more sections were abandoned on Glenelg Beach because the piles could not be screwed into the seabed in the designated spots.

COMMENCEMENT OF CONSTRUCTION

Construction of the original jetty commenced in August 1857. His Excellency the Governor, Sir Richard Graves MacDonnell, screwed in the first pile on Saturday 29th August 1857 in a ceremony with full Masonic honours.

COMPLETION OF JETTY

The completed jetty was 1,250 feet (381m) long, 18 feet wide and cost 31,294 pounds to build. It consisted of 61 bays 20½feet wide. The distance between the handrails was 18feet. Eight-inch diameter hollow poles were used with two-foot diameter screws at the end. The screws had a pitch of 5¼inches (turns of the screw thread?). The piles at the extreme end of the jetty were screwed 11½feet into the sand. The opposite piles of each bay were connected together by a lattice girder. Lattice girders carried the longitudinal girder for fastening the planks to the jetty.

OPENING THE JETTY

Governor MacDonnell opened the jetty at 2pm on Monday 25th April (Anzac Day) in 1859 in another huge ceremony.

FIRST CARGO UNLOADED

The first cargo to be unloaded at the jetty was coal from the barque "Anna" on 15th November 1865.

ROYAL VISIT

On 1st November 1867 Queen Victoria’s second son, HRH Prince Alfred, Duke of Edinburgh, was brought to the jetty by launch from HMS Galatea which had anchored in the bay on the previous day. The Duke was 24 years old and he was in command of the Galatea which had a displacement of 3,227 tons. D.Perry's book "The Place of Waters" features a drawing of the Galatea on page 54.FIRST LIGHTHOUSEWork commenced on building a wooden lighthouse on the southwest corner of the seaward end of the jetty in 1871. It was completed in 1872 but caught fire in 1873, threatening the jetty itself. It had to be chopped free and pushed into the sea to save the jetty.

L-HEAD ADDED

An L-head made of jarrah wood was added to the jetty in 1873.

SECOND LIGHTHOUSE

A replacement lighthouse was built in 1874 on the northwest corner of the end of the jetty. This second lighthouse was a 40 feet iron structure with gaslight.

BUSY PORT

Glenelg became a busy port with the opening of the railway from Adelaide. The jetty was fitted with steam cranes to unload freight and rail lines ran to the end of the jetty. These rails were, however, just for hand trucks which could be taken to the rail terminus.

ARRIVAL OF MAIL

From 1874-88 the mail steamer (P&O) from England would anchor offshore and transfer the mail to smaller craft which would then be unloaded by crane at the jetty.

Upto 1881 the "Harriet Hope" was always anchored about one mile west of the jetty (1½mile from shore) to serve as a store for coals for the mail steamers, and also to indicate the anchorage. This vessel, known as "the hulk", would show two vertical lights at night and fire a gun whenever the mail arrived or departed.

Rockets were thrown up whenever the lights of the mail steamer came into sight at night and blue lights were shone from the end of the jetty. If the steamer arrived during the day, the company's flag (P&O) was hoisted on board the hulk and the rendezvous flag was hoisted on the lighthouse flagstaff.

(Much of the above information is reported in detail by John Lee in his book "Glenelg Historic Guide and Directory 1883" (Advertiser General Printing Offices).)

In 1881 the schooner "Beatrice" was stripped down and moored in place of the "Harriet Hope" which had been transferred to Port Augusta. The "Beatrice" was a 94-foot two-masted wooden schooner built in 1860. She acted as a marker assisting the mail steamers at Glenelg until 1888 when she transferred to Semaphore. When lights were installed to assist mail steamers the "Beatrice" returned to commercial service. She ultimately became wrecked near Port Lincoln in 1897.

FISHING BOATS

Commercial fishing boats used the jetty and their catch would be railed to Adelaide. Oysters unloaded at Glenelg would be placed in bags in the water until they could be delivered.

PORT ADELAIDE

Port Adelaide became Adelaide's major port and it soon became obvious that Glenelg’s future would be as a resort.

Steve Reynolds

To be continued in future Newsletters.

 

"Landing of the first mail" (1874)

On 6th February 1874 (six months after the opening of the Adelaide-Glenelg rail service) the first of the P&O Mail Ships to call at South Australia anchored off Glenelg. The ship was the Bangalore. She carried passengers, mail and cargo. The passengers were transferred from the ship to the jetty by launches. The mail and cargo was transferred to the jetty by a lighter. Awaiting trains conveyed everything to Adelaide. The picture shows one of the trains at the entrance to the jetty. The Bangalore may be the sailing ship south of the jetty. The L-head built in 1873 can be seen at the extreme outer end of the jetty. The large building on the shore is the original Pier Hotel which had been built by Henry Moseley in 1856. (Moseley built his own home on the allotment to the south of his hotel.) Work on the construction of the jetty began in 1857.

The picture is from the author’s own collection. The original picture was an engraving which was first published in the "Australasian Sketcher" on 21st March 1874, page 212. That copy of the picture is held by the National Library of Australia in Canberra. A copy of the picture features in the book "The Place of Waters" by Dulcie M. Perry, page 61.


2002 Annual General Meeting

We had a large turnout at the AGM. This was very gratifying and no doubt partly due to the excellent speaker for the evening. This was Scoresby Shepherd who talked about his experiences in the Galapagos Islands in a most entertaining and enlightening way.

A wide selection of food and drink was enjoyed during the break and the informal discussions taking place.

There being only the required number of executive nominations these were confirmed. They are as follows:

President: Philip Hall

Secretary: Steve Reynolds

Treasurer: Phill McPeake

Committee Member #1: David Muirhead

Committee Member #2: Chris Hall

The non-executive positions were filled as follows:

Editor: Philip Hall

Diving Officer: Maggie McGilchrist

Assistant Diving Officer: Steve Reynolds

Webmaster: Danny Gibbins

Assistant Webmaster: Maggie McGilchrist

Librarian: Steve Reynolds

Con. Council Representative: Vacant

Reefwatch Representative: Alex Gaut

S.D.F. Representative: Steve Reynolds

Assistant S.D.F. Representative: Geoff Prince

Photo Index Officer: Steve Reynolds

Auditor: Phil John

Our thanks go to all who nominated and we hope for a successful and productive year.

Philip Hall

  


From "Wet Stuff"

Marine Archeology
http://www.nature.com/nsu/020429/020429-17.html
Old Balls Still Scorch - Pores Made Shipwrecked Cannon Balls Glow Spontaneously.

David Adam 6 May 2002


Goodness gracious! Two British chemists believe they have solved the 26-year-old mystery of how shipwrecked cannonballs that were rescued from the deep spontaneously erupted into great balls of fire.

"They were glowing bright red and you could feel the heat coming off them as the desk began to smoke," recalls Bob Child, now a chemist at the National Museums and Galleries of Wales in Cardiff.

It all happened in 1976, when Child was conserving artefacts recovered from HMS Coronation. Among the haul from the 1691 wreck were several dozen iron cannonballs, encrusted in a concrete-like coating from three centuries beneath the waves. Breaking off this airtight layer with a hammer, Child recalls being "bloody amazed". Several of the cannonballs spontaneously began to heat up, so violently that they almost set fire to the wooden desk on which they were sitting. Child estimates that they reached temperatures of 300-400 °C.

Now he and fellow chemist David Rosseinsky, a visiting fellow at the Gintic Institute in Singapore, think they know why. After the Coronation sank, the conditions on the seabed, that of surrounding by salty, oxygen-rich water allowed the iron balls to rust almost all the way through. This would have caused them to expand, making them less dense. Indeed, the recovered balls were much lighter than expected. At the same time, the cannonballs were gradually sinking into the sand, which reacted with the metal to form an airtight seal around them.

Over the decades, rotting organic matter that was entombed along with the oxidized metal converted it back into pure iron. Crucially, the volume remained the same - leaving pores where the iron oxide had been. When the seal was broken, air permeated these pores, with dramatic results. Corrosion researcher Stephen Fletcher at Loughborough University, UK, explains that it is not unusual for finely divided iron to heat up rapidly when exposed to air. As iron oxidizes it releases energy, and the huge surface area of the fine filaments means that this happens so quickly that they can actually burn. Hand-warming devices for Arctic explorers, round-the-world sailors and British holidaymakers exploit this phenomenon. "But you just don’t expect a solid cannonball to be made up of finely divided and compressed iron powder," says Rosseinsky.

Recent interest in the difficulties of conserving artefacts recovered from the sea persuaded Child to re-examine the mystery in an attempt to explain what had previously been an interesting conversation-starter, he says. Other researchers will have the opportunity to test his and Rosseinsky’s conclusions - if they can wait another 300 years or so.

© Nature News Service / Macmillan Magazines Ltd 2002

Wet stuff is compiled from a range of web sources by the MCCN (SA)and distributed as a free community service for the purposes of non-commercial education, research and study; review and the reporting of news; and archived for reference of students and researchers as a ‘fair dealing’ activity under Australian Copyright Law.
NOTICE: In accordance with Title 17 U.S.C. Section 107, this material is distributed without profit to those who expressed a prior interest in receiving the included information for research and educational purposes.

The MCCN is a national program supported by the Australian Federal Government's Natural Heritage Trust.


Christmas Island Film Shown At Our April Meeting

MLSSA members Mike Piper and Vicki Harris showed us one of their films at our meeting in April. It was a film about the red crabs of Christmas Island. The crabs were said to be nature’s consummate gardeners. They till the soil, clear away leaf litter and weeds, and control the regeneration of rainforest plants. The island is over 70% rainforest and the crabs are nature’s custodians of the forests. Without the crabs, the unique composition of the island’s rainforests would change forever.

Each year millions of red crabs migrate to the island’s coastline for a mass spawning. It is one of the most extraordinary biological events on earth. During the migration the crabs face many threats and hazards. Cars, moray eels and robber crabs all threaten the existence of the millions of crabs but it is a tiny creature that is their biggest concern. Yellow Crazy Ants are creatures no bigger than a fingernail but they pose the greatest threat to the crabs. They are an introduced species accidentally introduced some 50 years ago. These tiny creatures are able to subject the crabs to a slow painful death. As they crawl over and around the crabs they release formic acid, spraying it onto the eyes of the crabs and into their mouth openings. The crabs become stressed and spend up to 12 hours dying. Crabs which survive the attacks are able to spawn. The female crabs produce up to 100,000 individual fertilised eggs. These are released into the sea where they hatch into larvae within seconds. Baby crabs that return to the shore and attempt to reach their rainforest abitat are themselves attacked by the acid spraying ants. They die in their millions. The tiny killers are rapidly spreading over the island. Their increase in numbers and the loss of so many red crabs is altering the island’s ecology. Many thanks to Mike and Vicki for showing the film to us at our meeting. After the film we were able to ask them lots of questions.

Steve Reynolds


The Distribution of Port Jackson Sharks (& Wobbegongs)

In April we received the following email request :-

"I am looking for anecdotal information of the distribution of the Port Jackson Shark; Anecdotal reports from divers and fishers of an abundance of several shark species (e.g. wobbegong and Port Jackson shark) including breeding and nursery areas for Port Jackson shark in the bays on the south-western "toe" area of Yorke Peninsula.
Thanks,

Rosemary Paxinos

Marine Information Officer Office for Coast and Marine

Ph: 8207 1870 Fax: 8226 0004 Mob: 0407 200 853"


I passed the request on to Society members and SDF contacts on e-mail. Here are some of the responses received.

"Since 1973 I have been hatching Port Jackson sharks for educational purposes in classroom based aquaria. My first teaching appointment was at Port Augusta and the area now regarded as the cuttle breeding grounds near Point Lowly (Whyalla) was the source of eggs during February each year. These eggs are noted to be hatching several months sooner than eggs sourced from places like Edithburgh and Second Valley. Over 95% of the eggs have been sourced from the three places mentioned above. There has NEVER been a time when eggs were not found when required and this year the source at Edithburgh was particularly easy to spot. Hundreds of eggs were obvious against the sandy patches between the jetty and the public swimming pool. Many were old or fouled by predatory gastropods. Several were advanced in development while others were still sealed and not able to be inspected for viability. The usual place to find the eggs is at the base of Eklonia in the voids provided by the rock. Where there is one there are usually several and some years only one at a time can be a pattern. Evidence of communal nesting sites is clear and numbers do seem to vary a bit. At Edithburgh the eggs can be wedged in rock that is quite shallow at low tide (e.g. 1-2 metres). Distribution elsewhere is highly probable but, for reliability and convenience, I’ve only gone to a few places so that I could gauge the sustainability of my educational practices. The largest full sized wobbegong that I’ve ever seen was at Second Valley near the fishers’ sheds back in March 2002. It was quite placid and I directed about a dozen divers to view it. I was getting out at the jetty while they were entering.....apparently all of them got a good look. About 10 years ago, a one metre long wobbegong was at the Horseshoe reef, Christies Beach. I've seen none during the time between these two sightings in SA. Sharks are hatched (in vitro) at Port Vincent School, Star of the Sea (Henley Beach) and at Hallett Cove R-12 school. Ben of the Below Decks Shark Aquarium off Granite Island is hatching one in the aquarium set up within the cafe/gift shop on the Island. Its development is about 3 to 4 weeks behind what is growing at Star of the Sea and Hallet Cove. All should "hatch" by July/August. In the wild, and at cooler temperatures, the eggs could hatch after the new season eggs are laid (October-December)." – Tony Isaacson

"I am aware of sightings of large numbers of Port Jackson sharks in Victorian waters, having sighted many individuals and larger numbers (up to a dozen or more) in reefs within Port Phillip Bay and the Port Phillip Heads region. Mostly found in caves or overhanging reefs where they lie motionless. I have however seen them in a mating game, I guess you'd call it, on the reefs of one of Victoria's proposed Marine Parks areas (Rickett's Point). I have also sighted many sharks including wobbegongs on the southern coast of NSW and as far north as Byron Bay." – David Bryant

David Muirhead provided information from his MLSSA Newsletter article "Snorkel At Gleeson’s" as follows:-

"While holidaying at Hardwicke Bay at Easter I felt drawn to the old haunt (Gleeson’s Landing) and four of us managed to squeeze in a half hour snorkel in quite good conditions with a light offshore breeze and 7 metre visibility."

"The standout feature of the snorkel was a group of at least seven Port Jackson Sharks (Heterodontus portusjacksoni) in a small area of shallow reef, depth 2 - 4 metres. With scuba we may have located more. These fish were all adults with 3 or 4 heaped together and the others within a few metres, under ledges close to the reef platform.

This common species congregates seasonally in shallow water to mate and such behaviour has been reported much closer to home at Aldinga Reef. Whilst not in the same league as the annual great Cuttlefish action near Whyalla, being witness to this gathering gave this snorkel that special touch.

Hence egg-laying sharks have a remarkably ancient lineage and really are the dinosaurs of the sea. The eggs have a distinctive chitinous base with a double spiral flange and the female protects her newly laid eggs by wedging them in rock crevices with her mouth.

The Port Jackson Shark’s teeth are adapted for its diet of predominately hard-shelled organisms such as molluscs, sea urchins and crustaceans. Its sharp front teeth contrast with the more prominent molar-like rear teeth suited to crushing and grinding, hence the genus name Heterodontus." - David Muirhead

I myself told Rosemary that I had recently sighted a few Port Jackson sharks at Port Hughes and Port Noarlunga. Two were sighted together in a small cave on the outside of the Port Noarlunga reef. I wrote in our 1993 Journal (No.4) that I had sighted some seven sharks in a small cave at Victor Harbor (The Breeding of Sharks, Stingrays and Skates).

Steve Reynolds