Aquaviews - SCUBA Blog » sharks

Meet A Small Shark With A Mighty Bite- The Cookie-Cutter Shark

Noreen — Wed, 02 Feb 2011 16:04:48 +0000

At only 42-56 cms long (17-22 inches), the cookie-cutter shark is one of the smallest species of shark and doesn’t seem much longer than two pencils put end to end. But, don’t let it’s little size fool you. Also known as the cigar shark because of it’s long cylindrical body, this little guy packs a mean bite and takes round plug like chunks out of his victims, which is how he got tagged with the cookie-cutter name. But, it’s not cookies made of flour and sugar he snacks on, but rather of tuna, whales and even other sharks more than ten times it’s size.

The cookie-cutter shark inhabits the deep ocean and compared to other creatures of the deep, he may seem harmless and not in the least bit frightful. However, if you happen to get a peek at his teeth from his underside, lets just say, you wouldn’t want him taking a nip at you. The cookiecutter shark has 30–37 tooth rows in the upper jaw and 25–31 tooth rows in the lower jaw, however his upper and lower teeth are distinctly different. The upper teeth are small narrow and tapered, while the lower teeth are broader and knife-like, with their bases interlocking to form a single saw-like cutting edge. It also has think lips that enable it have suction to latch onto it’s victim in a parasitic manner, before it twists its body, scooping out a chunk of their flesh and leaving a rounded wound that looks as if it were punched out by a cookie cutter.

These bite marks have been spotted on a huge variety of large marine species such as whales, porpoises, dolphins, seals, deep water pelagic fish (tuna, dolphinfish, jacks etc), squid and other shark species like goblin sharks, blue sharks and the mega mouth shark…phew! That is quite the list for a little guy huh?

What helps the cigar shark snag its meals other than the unusual mouth, is the fact that it has some light-emitting organs called photophores that give the shark’s underside a greenish glow. This helps it’s silhouette appear like a small fish to predators swimming below and attracting their attention. When their curiosity draws them close, the little shark makes its move and latches on to take a bite.

The cookie-cutter shark being small, a deep water inhabitant and not very fast in terms of attacking speed, isn’t usually considered a danger to humans. However, this little creature has managed to put his mark on a few people around the world according to reports. Mostly reports were from shipwreck survivors that displayed small, clean but deep bites during night time and one case of an underwater photographer on an open ocean dive. Other reports are of bodies that were recovered from the water with cookiecutter shark bites, not being the cause of death though.

Fascinating isn’t it, what a mighty bite this tiny little shark has. Makes me re-think doing deep dives at open ocean dive sites.

*Image credits: NOAA Observer Project and George Burgess, Florida Program for Shark Research, Florida Museum of Natural History

Gordon Ramsay’s Shark Bait

Nevin — Fri, 21 Jan 2011 14:24:06 +0000

We’ve all seen Gordon Ramsay of Hell’s Kitchen and Kitchen Nightmares fame, scream at people, throw sauce pans across the kitchen or curse like a salty sailor on reality TV shows, however this time around, the Michelin star Celebrity Chef shows us a softer side of himself. In this provocative, investigative documentary film about the Shark Fin trade, Gordon Ramsay’s Shark Bait is a journey’s from the consumers of Shark Fin soup right to the fisherman who carry out illegal shark finning half way across the world.

There is an estimated 100 million sharks being killed worldwide and a third of the world’s open ocean shark species being driven to extinction by overfishing, simply because of one dish.. Shark Fin Soup. Fisherman fetch exorbitant rates for the fins of the shark, and little or nothing for the carcass, which has led to the wasteful and cruel practice of shark finning, which essentially means cutting off the fins of a live shark and throwing back the creature into the water to die after harvesting its fins.

The journey of the documentary begins at London’s China Town where Gordon uncovers an alarming number of restaurants serving up Shark Fin Soup. He then travels halfway across the world to Taiwan where he discovers a staggering amount of shops and restaurants all selling shark fin. Taiwan is the largest centre of both the shark-fishing industry and shark-fin consumption, and here Ramsay gets his first taste of the famous shark fin soup, and isn’t at all impressed by its flavor, stating that it tastes like nothing and doesn’t even add to the soups flavor which is mostly stock of ham and chicken.

Gordon’s love of sharks leads him on his this personal mission to investigate the fishermen at Taiwan’s fishing piers where he faces resistance and cover-ups along the way. Scenes of hundreds of shark fins drying on rooftops near the docks are simply staggering, especially when one has to comprehend that for every three or four an entire adult shark is killed, irrevocably driving the oceans apex predator to extinction and causing an unknown impact on our worlds oceans.

From the shocking consumption of Shark Fins in Taiwan, Gordon Ramsay then moves on to the source of illegal shark fishing in Costa Rica where the industry is so lucrative that huge private docks with fortified walls have been set up to protect shark finning businesses from the prying eyes of the law. Gordon gets to experience first hand the frowned upon practice of long line fishing in Costa Rica where fishing line baited with hundreds of hooks draw up hundreds of sharks and other innocent sea creatures such as sea turtles which is difficult potion to watch.

Finally to understand more about the Sharks, Gordon, a known lover of scuba diving, takes the plunge to scuba dive with the deadly bull shark in Costa Rican waters, his scariest challenge to date, where he comes face to face with a couple of massive Bull Sharks.

Overall Gordon Ramsay’s : Shark Bait which aired on Sunday 16th January at 9pm on Channel 4 was a must watch film and a real eye-opener to the world of Shark Finning, leaving one to wonder to what extent will man go to appease his fancy.

15 Fascinating Shark Facts

Nevin — Wed, 12 Jan 2011 15:18:50 +0000

Sharks, We fear them, yet we are fascinated by them. What makes this apex predator of the seas so appealing to us? Well here are fifteen fascinating facts about sharks that should get you even more curious about these frightening fish:

1. There are 355 confirmed species of Shark ranging in length from 15cm to 15 meters

2. Most other fish have skeletons made of bone. A shark’s skeleton is made of cartilage, a type of strong but flexible tissue.

3. Sharks have been around for about 400 million years – long before dinosaurs even existed

4. Sharks have extremely sensitive hearing. They can identify much lower sounds than human ears can detect, and some can hear sounds more than 700 feet away. Some scientists think hearing is typically the first sense sharks use in detecting their prey.

5. Great White Sharks can go up to three months without eating

6. Sharks will often eat other sharks

7. The first pup to hatch inside the sand tiger shark mother devours its brothers and sisters until there are only two pups left, one on each side of the womb. This form of cannibalism is called oophagy

8. Two-thirds of a Sharks brain is dedicated to the sense of smell.

9. Some sharks can smell one part of blood in 100 million parts of water and can tell which direction that smell is coming from

10. Most sharks have at least four rows of teeth and they never run out of teeth – when one is lost another spins forward from the rows of backup teeth

11. A shark may use over 20,000 teeth during its life

12. Sharks can be found in all of Earth’s oceans

13. Portuguese sharks live at depths of 12,000 feet, which is over two miles deep

14. As long as a shark’s back is mostly under water, it can swim easily. A nine-foot-long bull shark can swim in just two feet of water

15. Sharks may use the Earth’s magnetic field with special organs that act as a compass to navigate the oceans

Scuba Humor: Shark Comics by Phil (Shaaark.com)

Noreen — Mon, 06 Dec 2010 16:00:53 +0000

We’ve done a lot of articles here on Aquaviews about Sharks and Shark Attacks; from serious ones like- The Cruel Truth About The Biggest Predators of the Seas & Sharks , Overcoming The ‘Jaws’ Factor When You Dive, Shark Facts And Fish Tales: 5 Biggest Misconceptions About Sharks to ones written in a lighter spirit like 5 Steps to Avoid A Shark Attack or 5 Things More Likely Than a Shark Attack. It was a real delight to come across these funny Shark comics by cartoonist Phil of the Shaaark.com comic strip. Here’s his take on some good ol’ shark humor-

For more of Phil’s comics visit www.shaaark.com

5 Things More Likely Than a Shark Attack

Noreen — Fri, 22 Oct 2010 16:00:37 +0000

Guest Article By David Harmon of TheDivingBlog.com

Humans have an irrational fear of sharks. Most of this, I believe, is simply fear of the unknown. We don’t understand sharks nor most of the ocean and this frightens us. Combined with their poor treatment by the media and entertainment world, sharks overall get a bad rep. I’m here today to balance the score a little. Statistics put the risk of a shark attack worldwide at about 1 in almost 300 million. That’s a 3 with 8 zeros behind it! And this is only taking into account those who actually go in the water, not your Aunt Mildred who thinks the ocean is “dirty”.

That’s a big number, and big numbers don’t usually mean much to people. Let me put in in more relate-able terms. Here are 5 things more likely to happen to you than getting attacked by a shark:

Win an Academy Award. Over 50 Oscars are given out each year (including scientific and technical award winners), meaning you are more likely to win the coveted gold statuette this year than get bitten by a shark. Better get crackin’ on that script!
Die while scuba diving. While it sucks to think about, over 100 people die a year while scuba diving, often from unknown causes. You’re more likely to die while scuba diving from something like an equipment malfunction than to get attacked by a shark. There, don’t you feel better?
Dealt a full house—three times in a row. The odds of getting dealt a full house (three of a kind and two of another kind, one of the highest hands in poker) is 1 in 693. Let’s say you spend all night playing poker with the guys. You are more likely to get dealt a full house three times in a row than get bitten by a shark. Just how much money did you win last time you played poker?
Killed by a falling aircraft. In murky waters everyone’s on the lookout for killer sharks. How often are you on the lookout for falling aircraft? Instead of the Great White Shark you should be looking out for the Great White Airbus.
Win a Nobel Prize. Six prizes are awarded. This actually makes your odds of winning any one year lower than getting bit by a shark. However, factor in how often they are awarded, and your odds quickly zoom past shark territory. In fact, in any one year you are more likely to become a nobel laureate (nominee) than get attacked by a shark. Isn’t it nice to know that the Nobel prize committee cares more about you than Jaws?

Now don’t you feel ridiculous? These numbers are only for getting attacked by a shark. Let’s say lightning strikes and you do get bitten (actually, the chance of you getting struck by lightning is orders of magnitude greater than getting attacked by a shark). Even then, the chance of you dying is still very small (about 1 in 30).

The problem, of course, is that no one lives by statistics. Rather, we live by our emotions. Next time you feel yourself getting a little irrational, start running the numbers in your head. If worse comes to worse, who knows, maybe the sharks will decide to leave Rain Man alone.

About the Author: David Harmon is a PADI Divemaster, founder of “The Diving Blog” and all-around scuba enthusiast. His scuba blog records his learning curve & experiences as he journeys on to becoming a certified instructor. Catering to all levels of divers it discusses issues, offers tips and educates about all things subaquatic!

*Image Credits: photo by egarc2 on flickr

Shark Facts And Fish Tales: 5 Biggest Misconceptions About Sharks

Noreen — Wed, 22 Sep 2010 14:51:29 +0000

Embed This Image On Your Site:
<a href="http://aquaviews.net/shark-myths-facts-infographic/">[Source: <a href="http://aquaviews.net/"><a href="http://aquaviews.net">AquaViews</a>.net<a>]

The White Shark Café

Nevin — Thu, 16 Sep 2010 17:35:46 +0000

The White Shark Café is not your typical local barista serving up mocha lattes and cappuccinos. This “café “ located somewhere in the middle of the Pacific Ocean between the Mexican Baja Peninsula and Hawaii is a site where a peculiar phenomenon involving Great White Sharks takes place each year.

In 2000 Marine biologists, oceanographers, engineers, computer programmers, came together with NOAA’s Pacific Fisheries Ecosystems Lab, Stanford’s Hopkins Marine Lab, and University of California, Santa Cruz’s Long Marine Laboratory to form TOPP Tagging of Pacific Predators, an ambitious feat to conduct a marine census by tagging marine animals and tracking them via satellite.

Over 150 Pacific Great White sharks were tagged with GPS transmitters along the entire pacific coastline by TOPP, and led to a fascinating yet puzzling discovery regarding the behavior of Pacific Great Whites. The results of the research showed that each year in the winter, Great White Sharks in the Pacific perform a predictable and yet mysterious migration, leaving their favorite seal feeding grounds, near the coastline to travel 2000 Kilometers off the California Coast to a deserted stretch of ocean, an 400 mile-wide area with no distinctive underwater features, hardly any food in terms of prey, and spend up to 6 months at this site diving to incredible depths.

Once at the site known as White Shark Café, the Great Whites will perform repeated dives from 700 to up to 2000 feet and re surface every 16 minutes or so. Scientists are at a loss to explain the reasons as to why the Sharks arrive each year at the same spot and perform this mysterious ritual. Many believe that this is a mating ritual of the Great Whites, where they congregate once a year to mate. However the studies have shown that many juvenile Great Whites also perform the pilgrimage each year which indicates there might other reasons for the existence of the Café. Researchers have proven that there is no coinciding tuna or other large shoals passing by the site, which has hardly any plankton or sea life, which eliminates food as a cause of the migration.

Perhaps future research expeditions to the site will uncover the cause of this mystery of nature aptly nicknamed the White Shark Café.

The Secret Shark Pits – A Must Watch For Ocean Enthusiasts

Noreen — Tue, 14 Sep 2010 17:00:37 +0000

I recently had the pleasure of stumbling across one of the most interesting TV Documentaries I had seen in a while. National Geographic Channel’s – Secret Shark Pits.

In the waters surrounding Africa’s Mauritius Island in the Indian Ocean, local diver and naturalist Hugues Vitry discovered what he calls “the Shark Pits”, a phenomenon and spectacle that no one can explain. The labyrinth of reefs, caverns and caves around the volcanic island feature sunken pits which seem to hold some sort of magnetic attraction to sharks and they congregate in these pits not just by the dozens, but hundreds! What’s more mysterious is the behavior the sharks (mostly grey reef or blacktail sharks) display here is not typical of what would be expected.The display almost not no aggression, which is said to be quite unusual for a species of shark known for its threat display when cornered. And more intriguing, they do not swim constantly, which is all the more bizarre when it is known that grey reef sharks have to keep moving in order to breathe.

The show features two divers- Hugues Vitry and shark scientist, Ryan Johnson into the pits to witness the fascination spectacle that are these shark pits.

Here’s a sneak peek of the first episode that aired on the 6th of September, but catch the next one on Thursday 16 September at 17:00 on Nat Geo Wild (Repeats: Thursday 16 September at 23:00 on Nat Geo Wild and Friday 17 September at 05:00 on Nat Geo Wild).

Halle Berry Dives With Great Whites For New Movie

Nevin — Sun, 01 Aug 2010 17:33:00 +0000

Scuba Divers, if you’ve ever wished to see what Halle Berry would look like in a wetsuit, then your prayers have been answered! In her latest film ‘Dark Tide’, currently in production, Halle plays the role of a Scuba Diving Instructor in an action packed thriller. The Oscar-winning actress known to play some intense and diverse roles such as fighting villains in James Bond, or running with mutants in X-men, Halle has braved some tough acting challenges and in her newest movie, will once again be put to the test with the unique challenge of diving with great white sharks.

Dark Tide is a thriller centered on a diving instructor (Halle Berry) who returns to deep waters after a near-fatal encounter with a Great White shark. Directed by John Stockwell, who brought us surfing and scuba films such as Blue Crush and Into the Blue, Dark Tide attempts to uncover the terrifying emotional challenges and the test of courage to return to diving after having a terrible encounter with a Great White Shark. The film is scheduled for release in 2011.

Halle was spotted recently looking sexy in a bikini and wetsuit, donning her scuba diving equipment before getting into a shark cage aboard a boat while filming for Dark Tide in Seal Island, False Bay, South Africa. Seal Island is populated by 60,000 cape fur seals and is known to have waters teaming with sharks including the Great White which prey on their favorite food, the seals. Halle and the Dark Tide crew will be spending three months in South Africa filming the breathtaking underwater sequences in the heart of white shark country. Halle will actually be attempting cage diving in shark infested waters for the film.

The film has been criticized by shark experts in South Africa who claim that this new movie will only advance the fear of Sharks in general, and in particular, the Great White shark which already has a bad reputation fueled by Hollywood movies such as Jaws. The shark experts of South Africa wish to try to change people’s perceptions of sharks, and feel portraying a near fatal encounter with a great white and fighting off a shark in the movie will only serve to undo the work they have been trying to achieve.

photo from flickr by g-na

Dive the Cocos Islands in Costa Rica

Nevin — Sat, 24 Jul 2010 14:06:53 +0000

Cocos Island, Costa Rica is not a dive destination for the faint hearted. If you are a true hardcore diver, and aren’t afraid of large schools of pelagic fish, Sharks and Hammerheads, and don’t mind travelling a great distance to experience some of the best shark diving in the world, then Cocos Island is just the place for you.

Situated in the Pacific Ocean a mere 550 km (340 mi) off the coast of Costa Rica and just north of the famous Galapagos Islands, Cocos is an uninhabited speck of a volcanic island with an area of 23.85 km² (9.2 mi²) rising up from the Pacific depths. Covered in lush tropical rainforest, and speckled with hundreds of waterfalls, this enchanting island served as the backdrop for the filming of the movie Jurassic Park. Both the Island and the waters surrounding it are declared a Costa Rican National Park and are protected from fisherman or visitors by Costa Rican Park Rangers.

To get to Cocos Island, the nearest airport is located in the capital of Costa Rica, San Jose. From San Jose you need to travel by bus to the Pacific coastal town of Puntarenas which is the jumping off point to the Cocos Island. From Puntarenas you have three options, all live-aboard boats since there is no accommodation or even camping allowed on the Island. The three boats permitted to conduct dive operations are the Undersea Hunter, the Sea Hunter, and the Okeanos Aggressor each well equipped dive ships with experienced dive instructors who have been diving the islands waters for years. The trip from Puntarenas on the liveaboard takes approximately 30-40 hours, but the trip is well worth it once you finally arrive.

As enchanting as the island is, the main attraction lies below the surface which is why the Cocos Island was named one of the best 10 scuba diving spots in the world by PADI and numerous other dive authorities. From the largest schools of hammerhead sharks in the World, to eagle rays, manta rays, silky sharks, Galapagos sharks, sailfish, wahoo, jacks, and the list simply goes on and on! Schooling hammerheads are usually “guaranteed” sighting, and large vortexes of pelagic fish such as jacks are so common that fish at other sites elsewhere in the world will seem to pale in comparison. Large fish and predators seem to be the theme of every dive on Cocos, and you will probably get to see almost each and every species of shark and ray during the course of your trip.

The diving off Cocos Island is meant for the more experienced diver, as currents can be strong, dive sites deep with chances of being swept away into the open waters. Liveaboard diving is usually upto 5 dives a day and Some sites often require Nitrox or experience with rebreathers to get the bottom time necessary to enjoy the sites without scaring away the hammerheads. Almost every dive site is rated as Skill Level Advanced, so make sure you have the necessary degree of comfort in your diving skills if you plan to dive here.

Leisurepro Travel offers a brilliant Cocos Island Dive Package aboard the Okeanos Aggressor which includes 7 nights accommodations aboard the Okeanos Aggressor, airport and/or hotel transfers on day of charter, all meals, snacks, non-alcoholic beverages, local beer and wine, an average of up to 4 or 5 dives per day (depending on weather and itinerary), compressed air tanks, weights and belts. For more information visit LeisurePro Travel.

photos from flickr by g-na, ClifB, petersbar