About aldnz

aldnz has been a member since July 25th 2010, and has created 8 posts from scratch.

aldnz's Bio

aldnz's Websites

This Author's Website is

aldnz's Recent Articles

Unprovoked shark attacks

Shark attacks are on the increase due to more people being involved in activities like surfing and scuba diving. I saw this article in the National Post and the graphic showing deaths and shark attacks for the last 100 years, should make surfers very nervous. Blue or pink shows the person survived the attack, black means they didn’t.

Red Sea Shark Attacks

70 year old woman killed by shark in front of the Hayat Regency Hotel in Sharm el-Sheikh

A shark killed a 70-year-old German woman today. The attack happened in the sea directly in front of the Hayat Regency Hotel in Sharm el-Sheikh.
This is the second fatality due to shark attack in Egypt this year and follows a spate of attacks in the past few weeks.
The Egyptian Environment Ministry had claimed earlier in the week to have caught the sharks implicated in the attacks.
They displayed the sharks, a 7 foot Mako shark weighing 330 pounds and an 8 feet long Oceanic White Tip, weighing 550 pounds. The sharks were taken to Ras Mohammed Conservation Center to be dissected to see if there were any human remains inside.
Local divers who had seen the shark before the attack were adamant that the captured sharks were not the animals involved in the attacks. Even so the beaches were reopened and declared safe by the authorities.

Authorities claimed to have caught 'killer shark'

Mohammed Salem, director of Sinai Conservation said in an interview, “Usually these kinds of sharks don’t attack human beings but sometimes they have trouble with their nervous system and they accidentally go after people.”
In January of this year a French woman who was snorkeling in the Red Sea near Marsa Alam was attacked and killed by an unidentified shark. At the time the authorities blamed the woman for the attack, claiming: ‘This very rarely happens. It seems that the victim aggravated the shark or presented it with food, which caused a change in the shark’s behaviour,’
This latest fatal attack prompted tourism Minister Zoheir Garranah to order all beaches near Egypt’s Red Sea resort town of Sharm el-Sheikh be closed to the public and all maritime activities–including diving–be halted until the authorities could capture the shark.
One thing is for sure, a shark will be caught very soon, whether it’s the ‘killer’ remains to be seen, but the authorities cannot afford to close down one of the world’s most popular tourist destinations for watersports.
If someone else is killed, I wonder what excuse the authorities will dream up next?

Shark attack practical joke

I love this wetsuit, designed to look as though you’ve escaped a savage shark attack. It really is gruesome and I can imagine the reaction from other swimmers/surfers if you walked out of the sea wearing this suit. It does feel however that you’d be tempting fate. The designer is Diddo, who is obviously a very creative type. Although not yet in production, it’s my guess these will be collectors items in years to come. My absolute favourite is the Whaleshark patterned wetsuit. Funninly enough there’s no seal pattern available, now that would require big balls.

Shark attacks and blood myth busted!

I’ve always believed that sharks are attracted to the ‘smell’ of blood or urine in the water. So advice given to divers/snorkelers that to avoid shark attacks, you shouldn’t dive if you are bleeding, or you are a women who is menstruating and you should never urinate in your wetsuit, made sense. That is until I read this article by Devin Powell, Inside Science News Service. Read it for yourself and see if you feel reassured. “Everyone knows that sharks have an amazing sense of smell. Toss a chunk of salmon into the shark tank at the Monterey Bay Aquarium in California, and you can see it in action. “They know right away when the scent hits the water,” said Erin Carter, an aquarist at the Monterey Bay Aquarium who works with several species of sharks. “If it’s fresh food that’s just been delivered that morning from the dock, they’ll just go nuts for it.”
But can these aquatic bloodhounds really detect a drop of blood in an Olympic-sized swimming pool or a mile away in the ocean, as the popular legend suggests?
This myth smelled a little fishy to scientists in Florida, who decided to put it to the test. They found that sharks don’t live up to their reputation in the movies, documentaries, and pages of scientific journals. Although a shark’s sense of smell is extremely keen, it’s no better than that of a typical fish.
“From what we know now, they can’t smell a drop of anything in an Olympic-sized swimming pool,” said Tricia Meredith, a biologist at Florida Atlantic University in Boca Raton.
Blood In The Water
The idea that sharks have the best noses in the ocean may be partly inspired by our fears of the toothy predators.
“People are afraid if they pee or bleed into the ocean, sharks are going to sniff them out and eat them,” said Meredith.
In scientific circles, though, the shark’s smelly reputation is based on its anatomy. Unlike human beings, sharks have separate openings for breathing and smelling. Gills on the sides of their heads capture oxygen in the water, while two nostrils at the front of the face pull water into a nasal chamber where smells are detected.
The amount of tissue in this cavity, folded over plates called lamellae, is huge in sharks compared to other fishes. Scientists have long thought that this greater surface area gives sharks a better sense of smell.
“It’s a pretty logical jump to make, but no one had actually tested it,” said Meredith.
To test this assumption, Meredith studied animals from five different species of elasmobranchii — the scientific
subclass that includes sharks — captured in waters off the coast of Florida. They ranged from flat skates and stingrays to pointy-nosed lemon sharks and bonnethead sharks with hammer-like heads.

Each elasmobranch spent time in a tank with equipment attached to its nose: a tube that released 20 different kinds of amino acids — the building blocks of animal proteins that lead sharks to their prey — and an electrode that measured the electrical impulses in the nasal cavity generated in response to smells.
The recordings showed that, on average, sharks with more surface area in the folds inside their snouts were no better at detecting faint smells.
The five tested shark species had just about the same sensitivity as each other and as non-shark fish that have been tested in other studies. At their best, the sharks detected about one drop of scent dissolved in a billion drops of water.
One explanation for this is that being any more sensitive could actually confuse a shark. One part in a billion is roughly the natural background concentration of amino acids floating around in coastal waters. If sharks were adapted to detect smaller concentrations, it might be difficult for them to distinguish the byproducts of a potential meal from random bits of aquatic flotsam and jetsam.
“Imagine you were super-sensitive to sound, and you could hear whispering really well,” said Meredith. “That would be awful if you always lived in a room with a stereo blaring.”
When it comes to the myth of sharks having an unrivaled sense of smell, her conclusion is: “Myth busted.”
But for Jelle Atema, who studies shark olfaction at Boston University, the myth is only mostly busted. Although impressed by the new research, he said that the science leaves a little room for further exploration.
The electrodes in Meredith’s experiment work by adding up the entire electrical response of millions of smell receptors to a scent. Atema hopes to get a closer look by examining single cells — some of which might be specialized to respond to certain smells.
“Pretend that these smell receptors are a singing choir,” said Atema. “The choir itself may not be louder, but some voices may be singing louder than others if you listen closely.”
Meredith’s study focused on coastal sharks. Atema wonders if the same applies to sharks that live in the open ocean, where the background concentration of smells is lower.
His work has also shown that aquatic animals can detect extremely small concentrations of other chemicals that are not amino acids. Tuna can smell one drop of the chemical tryptophan — a common compound in turkey meat — dissolved in trillions of drops of water.
For now though, the best scientific evidence suggests an update to the popular myth: sharks can smell a drop of blood in a volume of water about the size of a backyard swimming pool. It’s still impressive, but hardly as terrifying as Hollywood would have us believe”.

Bahamas shark feed video

Wonderful video footage of placid sharks being hand fed by a ‘hypnotist’ scuba diver. Check out the shark in trance at approx 2 mins 30 secs.
Beautifully shot and the video shows how gentle sharks can be.

Copyright © Al Dickman 2006 About us