Diving Thoughts

The BBC have an article on tagging whale sharks in the Maldives.  The project apparently started last year and is the first attempt to tag whale sharks in the Maldives.  The research group involved are from the Maldives Whale Shark Research Programme. They are trying to photograph each shark between the fifth gill and the side fin on both sides. Then they have some software which examines the spot patterns to see if it is anew find. The spot patterns act like a human fingerprint in terms of identifying these sharks.

So far they have recorded 106 whale sharks, of which 104 are male. And we think that China has a problem with gender imbalance!

The sharks are tagged with tags that record temperature, depth and light level. They are using satellite tags which can be programmed to release and bob to the surface. Last year they were set to release in 9 – 12 months, but this year they are setting them at 100 days. In addition they use archival tags which have to by physically removed by cutting the tether.

The researchers are also carrying out DNA analysis to see how closely the sharks are related to each other and to other populations around the world.

The BBC site, from where the above photo comes, also has some good photos. Plus there’s a video of the story of Joey, a whale shark who is lucky to be alive after his dorsal fin was partially severed by shark finners.

The Maldives Whale Shark Research Programme also has a website, with in-depth information on the photograph and tagging programmes, as well as their campaign to set up a Marine Protected Area (MPA). There’s also some great photos.

SCMP is reporting that biologists in the Philippines have rescued a 38cm whale shark near Donsol, which may be the smallest known specimen of a whale shark found so far. It had been caught by fishermen and tied by its tail to a stick on the beach.

In 1996 an examination of a dead whale shark discovered a number of unborn embryos which measured between 37 and 48 cm. That  implies that this new whale shark is a baby and may have been born around Donsol.

Donsol is known for the large number of adult whale sharks which can be found there at certain times of year, and it has always been assumed that it is one of many feeding areas along their migration routes. Now this opens up the interesting possibility that it is more important and forms an area where whale sharks come to give birth.

The whale shark pup was released in deep water.

The photo above comes from an SCMP article.

Divers off eastern Australia are being urged to take along digital cameras, so they can take photos of any sharks they come across. Given the hysteria surrounding the recent attacks in Sydney, I originally assumed that it was a media circus idea, to help them identify the culprit in the event of any more incidents. I suppose even that would be progress, as up until now the media seem to believe there is only one species, i.e. the  “man-eating shark”, along with its sub-species, the “killer shark”.

Anyway it turns out the request comes from Sean Barker, a Macquarie University marine researcher, who is trying to compile a computerised photo album recording every grey nurse shark. In 2000 a New South Wales Fisheries survey estimated that there was less than 300 left on Australia’s east coast.  Mr. Barker reckons that is pessimistic and thinks it’s more like 1,000.

Apparently each shark has a pattern of dots,  highlighted in these 2 pictures, with which they can be uniquely identified. To help with this he needs photos, and has asked people to upload them to http://www.spotashark.com/. So if you are diving in that area and want to help out, you need to photograph the shark side on, from the tip of its nose to the tip of its tail. Apparently the left side is preferable.

You can find out more by going to Spot a Shark website (from where these photographs came), and there is an article in the Sydney Morning Herald.

Fishermen and rescue workers in Taiwan have managed to help a whale shark escape from a canal. It took them 8 hours to tow the shark back out to sea.  It is believed that the whale shark may have entered the freshwater canal while chasing food.

You can see a video from the BBC.

A 15 year old boy is recovering in hospital after being bitten by a shark while surfing with his father off North Avalon beach in Sydney. Andrew Lindop and his father Charles were surfing in the early morning on Sunday when a shark bit Andrew’s leg. His father managed to get him to shore and tied a tourniquet on his leg before an ambulance took him to hospital. He is apparently comfortable and recovering.

Here  is a link from Sydney Morning Herald.

Inevitably when there is blood in the water, the critics are circling, with Surfwatch Australia director, Michael Brown, complaining about the Government’s shark spotting and surveillance measures. Here’s another Sydney Morning Herald article.

The Sydney Morning Herald are reporting that scientists have examined the wounds sustained bya surfer on 12th February, and concluded that they were caused by a 2.5 metre great white shark.  Glenn Orgias was bitten while surfing at Bondi beach at around 8pm and suffered severe injuries to his hand. He is now stable in hospital.

Two days earlier a navy clearance diver was injured at Woolloomooloo by what is believed to have been a 2.7 metre bull shark.

According to an article in the Sydney Morning Herald, shark attacks worldwide have fallen from71 in 2007 to 59 in 2008.  But of these 4 were fatal in 2008 compared to only 1 in 2007. Surfers appear to be their victims of choice, making up 57% of the total. Divers account for 8%, with swimmers and waders making up the rest. Even so, these are very low numbers considering how many people use the world’s oceans.

George Burgess, an ichthyologist and director of the International Shark Attack File, which is housed at the University of Florida’s Museum of Natural History, thinks that this apparent decline could be partly because of the effects of the recession reducing the number of people holidaying on beaches.

A day after a navy clearance diver was injured by a shark, there has been a second attack near Sydney. This time off Bondi beach a 33 year old nearly lost his hand.

NSW Primary Industry Minister, Ian Macdonald, warned people not to swim at dawn or dusk.  Meanwhile an aquarist from Sydney aquarium questioned teh value of the shark nets, claiming that 40% of sharks caught in the nets are actually leaving the beach area. She sees the nets as glorified fishing tools designed to catch sharks rather than protect bathers.

You can read more from the Sydney Morning Herald.

An Australian navy diver has been seriously injured in Sydney Harbour after being attacked by a shark.  The 31 year-old was part of a clearance diving team based at HMAS Penguin and fought off the shark at Woolloomooloo  Bay.  Someone from the National Parks and Wildlife Service said that February and March is when you tend to get more sharks and surface fish in the harbour. The feeling is that this was a bull shark.

There is quite an extensive story in the Sydney Morning Herald.

Thanks to Brian who sent me this link to this You Tube video of a goblin shark (Mitsukurina owstoni). This peculiar looking shark has a very long snout, but it also has extendible jaws that look like the thing Sigourney Weaver was up against in Alien. It also has a mostly pink body due to blood vessels under a semi-transparent skin, which apparently bruises easily.

Goblin sharks live very deep and can be found throughout the world, living on squid, crabs and deep sea fishes. They can grow up to 11 feet long, and the snout contains organs that are electro-sensitive, which helps it find its prey in the dark of the deep oceans.

Kayakers off Sydney found themselves being circled by a 4-5 metre great white (white pointer) off about a kilometre off Long Reef, according to the Sydney Morning Herald, which also has a video of the incident.

The BBC also has some video of the shark.

So it seems to have been a busy time for sharks in Australia, although that’s probably largely because it’s a summer weekend over the Christmas holidays,  so more people are in the water.

A 51 year old, Brian Guest, who was snorkelling with his 24 year old son in waters near Port Kennedy south of Perth, is believed to have been taken by a shark.The incident happened at around 7am on 27 December while he was snorkelling for crabs in relatively shallow water.

Witnesses did report seeing a shark in the area. A search by six boats and a helicopter have failed to find Mr. Guest, although there are reports that part of a wetsuit has been found.

According to a news.com.au article, Brian Guest had told Western Angler website forums in 2004 and 2005 that he did not believe in killing sharks. Police have apparently said there would be no hunt for the shark involved.

You can read more from WAToday, the Daily Mail and the BBC.