Sharks Can Really Sniff out Their Prey, and This Is How They Do It

It's no secret that sharks have a keen sense of smell and a remarkable ability to follow their noses through the ocean, right to their next meal. Now, researchers reporting online on June 10th in Current Biology, have figured out how the sharks manage to keep themselves on course.

It turns out that sharks can detect small delays, no more than half a second long, in the time that odors reach one nostril versus the other, the researchers report. When the animals experience such a lag, they will turn toward whichever side picked up the scent first.

"The narrow sub-second time window in which this bilateral detection causes the turn response corresponds well with the swimming speed and odor patch dispersal physics of our shark species," known as Mustelus canis or the smooth dogfish, said Jayne Gardiner of the University of South Florida. All in all, it means that sharks pick up on a combination of directional cues, based on both odor and flow, to keep themselves oriented and ultimately find what they are looking for.

If a shark experiences no delay in scent detection or a delay that lasts too long -- a full second or more -- they are just as likely to make a left-hand turn as they are to make a right.

These results refute the popular notion that sharks and other animals follow scent trails based on differences in the concentration of odor molecules hitting one nostril versus the other. It seems that theory doesn't hold water when one considers the physics of the problem.

"There is a very pervasive idea that animals use concentration to orient to odors," Gardiner said. "Most creatures come equipped with two odor sensors -- nostrils or antennae, for example -- and it has long been believed that they compare the concentration at each sensor and then turn towards the side receiving the strongest signal. But when odors are dispersed by flowing air or water, this dispersal is incredibly chaotic."

Indeed, Gardiner explained, recent studies have shown that concentrations of scent molecules could easily mislead. Using dyes that light up under laser light, scientists found that there can be sudden peaks in the concentrations of molecules even at a distance from their source.

Gardiner's team suggests that the findings in the small shark species they studied may help to explain the evolution of the wide and flat heads that make hammerhead sharks so recognizable. One idea has held that the characteristic hammerhead may lend the animals a better sense of smell. But studies hadn't shown their noses to be all that remarkable, really. For instance, they don't respond to odors at concentrations lower than other sharks. The new findings suggest that the distance between their nostrils could be the key.

"If you consider an animal encountering an odor patch at a given angle, an animal with more widely spaced nostrils will have a greater time lag between the odor hitting the left and right nostrils than an animal with more closely spaced nostrils," Gardiner said. "Hammerheads may be able to orient to patches at a smaller angle of attack, potentially giving them better olfactory capabilities than pointy-nosed sharks." That's a theory that now deserves further testing.

In addition to giving insights into the evolution and behavior of sharks, the findings might also lead to underwater robots that are better equipped to find the source of chemical leaks, like the oil spill that is now plaguing the Gulf Coast, according to the researchers.

"This discovery can be applied to underwater steering algorithms," Gardiner said. "Previous robots were programmed to track odors by comparing odor concentrations, and they failed to function as well or as quickly as live animals. With this new steering algorithm, we may be able to improve the design of these odor-guided robots. With the oil spill in the Gulf of Mexico, the main oil slick is easily visible and the primary sources were easy to find, but there could be other, smaller sources of leaks that have yet to be discovered. An odor-guided robot would be an asset for these types of situations."

The researchers include Jayne M. Gardiner, University of South Florida, Tampa, FL, Center for Shark Research, Mote Marine Laboratory, Sarasota, FL; and Jelle Atema, Boston University Marine Program, Boston, MA, Marine Biological Laboratory, Woods Hole, MA, Woods Hole Oceanographic Institution, Woods Hole, MA.

Case Study Analyzes Why, Where and When of Leading Shark Attack Site

Shark attacks are most likely to occur on Sunday, in less than 6 feet of water, during a new moon and involve surfers wearing black and white bathing suits, a first of its kind study from the University of Florida suggests.

Researchers analyzed statistics from shark attacks that occurred in Florida's Volusia County, dubbed the "Shark Attack Capital of the World," between 1956 and 2008. They also spent a year observing people between Daytona Beach and New Smyrna Beach, said George Burgess, director of the International Shark Attack File at UF.

"It's basically an analysis of why, where and when in an area that traditionally has had more shark-human interactions than any other stretch of coastline in the world," he said. "One of our students, Brittany Garner, essentially camped out there, counted the number of heads on the beach and took photographs."

While this 47-mile-long section of Central Florida's Atlantic coast leads in human-shark skirmishes, making up 21 percent of all global attacks between 1999 and 2008, most are "hit and run" incidents that seldom cause serious injury and no fatalities occurred, he said.

"Calling them attacks is probably a misnomer because the consequences are usually no more severe than a dog bite," he said. "They're not the same kind of bites made by 10- to 20-foot-long white sharks that you have off the coast of California. Here we see a different style of attack, primarily perpetrated by smaller fish-eating sharks such as spinners and blacktips that are less than 6 to 7 feet long, which because of their size normally seek smaller prey."

There have been 231 shark attacks between the first one reported in 1956 in Volusia County and 2008, said Burgess, who works at UF's Florida Museum of Natural History. The study, part of which was published recently in the edited volume "Sharks and Their Relatives II," uses statistics from 220 of those cases for which detailed information is available.

Human, shark and environmental factors combine to create a perfect storm of favorable conditions in Volusia County for attacks, particularly near Ponce Inlet between Daytona Beach and New Smyrna Beach, he said.

The more people in the water the greater the chances they will encounter a shark, and New Smyrna Beach south of the inlet is a "hot spot" for surfers with its well developed sand bars and good waves, Burgess said. Hand splashing and feet kicking provoke sharks, which bite and release what they mistake for normal prey items in the turbid waters, he said.

Also, the strong tidal flow in the inlet makes it "an aquatic smorgasbord of food items for sharks, barracudas, mackerel and other large predators," boosting shark numbers, he said.

Young white males were attacked most because they spend the most time in the water, Burgess said. Ninety percent of victims were male, 77 percent of 196 victims were between 11 and 30 years old and in the 171 cases where race was known, 98 percent were white, he said.

Well over half of the 220 victims were bit on the leg -- 158 -- more than five times the number bit on the arms -- 34 -- the second highest body part to be injured, he said.

Surfers were the most frequent victims, making up 61 percent of the total, Burgess said. They tended to be bitten more in the early morning and late afternoon when waves were highest and they spend more time surfing, he said.

"At the time of the attack, most of the surfers were sitting or holding onto the board waiting for a wave, which explains why most surf victims were bitten on the legs," he said.

Sharks are not weekend warriors. Rather it is human leisure that leads to the fewest number of human encounters on Wednesdays and the highest on Sundays, followed by Saturdays, Burgess said. "There are a fair number of attacks on Fridays as well, reflective of people skipping work and taking three-day weekends," he said.

The greatest number of attacks occurred during new moons, followed by full moons, the edges of the lunar extreme when the moon has its biggest pull on the tidal phase, Burgess said. Probably the moon's phases influence the movements and reproductive patterns of fish, the shark's food source, just as they affect human behavior, he said.

Not surprisingly, attacks were highest during the swimming season, from May through October, peaking in August, Burgess said. They spiked in April as sharks began their seasonal northern migration up the eastern coast of the United States, he said.

Most incidents involved one bite, occurred in turbid, murky or muddy waters and were at the water's surface, Burgess said. Only one attack was on a diver, he said.

More victims wore swimsuits that were black and white than any other color combination, followed by black and yellow, attesting to sharks' abilities to see contrast, he said.

Between 1999 and 2008, shark attacks worldwide numbered 639, of which there were 428 reports in the United States, 275 in Florida and 135 in Volusia County. Burgess said.

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Florida. The original article was written by Cathy Keen.

Sharks from Deep Waters of Cantabrian Sea Are Opportunist Hunters

A team of Spanish researchers has studied the diet of three species of sharks living in the deep waters in the area of El Cachucho, the first Protected Marine Area in Spain, which is located in the Cantabrian Sea off the coast of Asturias. These animals feed on the resources available in their environment, according to changes taking place in the ocean depths."All the sections of the food chain are inter-related in these deep-sea ecosystems, and a small change in any one of the links in this chain can cause great changes in the rest," says Izaskun Preciado, lead author of the study and a researcher at the Oceanographic Centre in Santander, which is run by the Spanish Institute of Oceanography (IEO).In order to gain a detailed understanding of the species that inhabit El Cachucho (Spain's first Protected Marine Area located off the coast of Llanes in Asturias), the scientists studied three species of shark that live at depths of between 400 and 1,000 metres, the blackmouth catshark (Galeus melastomus), the velvet belly lantern shark (Etmopterus spinax), and the birdbeak dogshark (Deania calcea).The researcher says the results of the study, which has been published in the Journal of Fish Biology, showed that "the sharks' diet is opportunist, because they feed off whatever resources are available, in this case small euphausiid crustaceans, benthopelagic prawns and fish."The samples gathered between October 2003 and April 2004 made it possible to define two different habitats -- the top of the bank, at a depth of 454 to 642 metres and covered with a fine layer of sediments with a low percentage of organic material, and the interior of the inner basin, which separates the bank from the continental shelf, at a depth of between 810 and 1,048 metres.The study shows that the top of the bank (400-500 metres) is inhabited by two of the three shark species studied (the blackmouth catshark and the velvet belly lantern shark). "However, the velvet belly lantern shark is substituted in the deeper parts of the basin by the birdbeak dogshark," explains Preciado.In the deepest waters, the scientists sampled down to a depth of 1,100 metres and found that the blackmouth catshark and the birdbeak dogshark coexist there without any trophic competition between them, "since each one has specialised to eat a particular kind of food," says the oceanographer.The team stresses the importance of these studies in monitoring species in the El Cachucho area. "It is likely that the establishment of the Protected Marine Area will cause changes in the abundance of certain species of fish, above all commercial ones. For this reason, understanding the trophic network of these ecosystems will help us to predict future changes in the abundance of species," explains Preciado.The researcher warns: "A significant increase in a predator species could lead to a drastic decline in its prey, and so understanding the dynamics of the trophic networks will help us to predict changes in each of the sections of the ecosystem."The presence of larger blackmouth catsharks in shallow waters, for example, is a good indicator of higher levels of zooplankton production in these areas.El Cachucho is an undersea mountain located in the Cantabrian Sea, off the coast of Asturias. At around 4,500 metres in height (measured from its base on the deep-water plain of the Bay of Biscay), it has great faunal and biological wealth. It is the first exclusively marine reserve in Spain. To date, only parks such as Doñana, Cabrera and the Atlantic Islands of Galicia had extended their protection to include part of the maritime environment.

Jaws four Million BC: How an Extinct Shark Attacked Its Prey

It might sound like a mashup of monster movies, but palaeontologists have discovered evidence of how an extinct shark attacked its prey, reconstructing a killing that took place 4 million years ago.

Such fossil evidence of behaviour is incredibly rare, but by careful, forensic-style analysis of bite marks on an otherwise well-preserved dolphin skeleton, the research team, based in Pisa, Italy, have reconstructed the events that led to the death of the dolphin, and determined the probably identity of the killer: a 4-meter shark by the name of Cosmopolitodus hastalis.
The evidence, published in the latest issue of the journal Palaeontology, comes from the fossilised skeleton of a 2.8-meter-long dolphin discovered in the Piedmont region of northern Italy.
According to Giovanni Bianucci, who led the study: "the skeleton lay unstudied in a museum in Torino for more than a century, but when I examined it, as part of a larger study of fossil dolphins, I noticed the bite marks on the ribs, vertebrae and jaws. Identifying the victim of the attack was the easy part -- it's an extinct species of dolphin known as Astadelphis gastaldii- working out the identity of the killer called for some serious detective work, as the only evidence to go on was the bite marks."
The overall shape of the bite indicated a shark attack, and Bianucci called in fossil shark expert Walter Landini. "The smoothness of the bite marks on the ribs clearly shows that the teeth of whatever did the biting were not serrated, and that immediately ruled out some possibilities. We simulated bite marks of the potential culprits and, by comparing them with the shape and size of the marks on the fossils, we narrowed it down to Cosmopolitodus hastalis."
Circumstantial evidence also supports this verdict: fossil teeth from Cosmopolitodus are common in the rock sequences that the dolphin was found in. "From the size of the bite, we reckon that this particular shark was about 4 m long" says Landini.
Detailed analysis of the bite pattern allowed the researchers to go even further. "The deepest and clearest incisions are on the ribs of the dolphin" says Bianucci, "indicating the shark attached from below, biting into the abdomen. Caught in the powerful bite, the dolphin would have struggled, and the shark probably detached a big amount of flesh by shaking its body from side to side. The bite would have caused severe damage and intense blood loss, because of the dense network of nerves, blood vessels and vital organs in this area. Then, already dead or in a state of shock, the dolphin rolled onto its back, and the shark bit again, close to the fleshy dorsal fin."
The study is significant because of the rarity of such 'fossilized behaviour'. According to Dr Kenshu Shimada, fossil shark expert at DePaul University and the Sternberg Museum of Natural History in the US, "studies like this are important because they give us a glimpse of the ecological interactions between organisms in prehistoric seas. Shark teeth are among the most common vertebrate remains in the fossil record, yet interpreting the details of diet and feeding behaviour of extinct sharks is extremely difficult. Fossil remains of prey species with shark bite marks, like those described by Bianucci and his team, provide direct evidence of what each prehistoric shark ate and how it behaved." Giovanni Bianucci, Barbara Sorce, Tiziano Storai, Walter Landini. Killing in the Pliocene: shark attack on a dolphin from Italy. Palaeontology, 2010; 53 (2): 457 DOI: 10.1111/j.1475-4983.2010.00945.x

New Forensic Technique Gives Clues About Sharks from Bite Damage

Hit-and-run attacks by sharks can be solved with a new technique that identifies the culprits by the unique chomp they put on their victims, according to a University of Florida researcher and shark expert.

In a method analogous to analyzing human fingerprints, scientists can make identifications by precisely comparing shark bites to the jaws and teeth of the powerful predators, said George Burgess, director of the International Shark Attack File, which is housed at UF's Florida Museum of Natural History.
"Every time we investigate a shark attack one of the pieces of information that we want to have is what species was involved and what size it was," he said. "Because I've been looking at shark attack victims for 30 years I can estimate what did the damage, but I have never been able to actually prove it."
Now scientists can say with a degree of certainty whether the beast was a 14-foot tiger shark or a 9-foot bull shark, a distinction that has unforeseen emotional, ecological and even monetary benefits, said Burgess, who collaborated with researchers from the University of South Florida. Their findings are published in the November issue of Marine Biology.
"There's a psychological need for many shark attack victims to know what bit them," Burgess said. "One of the few things shark attack victims have going for them after a bite is bragging rights and the bragging rights include knowing what did the damage."
Because of the hype surrounding shark attacks, off-the-cuff estimates of shark size are often exaggerated, he said. "This will give an actual basis for determining what species was involved and the size, not that that's going to affect the size claimed by the victim in a bar," he said.
Using dried shark jaws from museums and private collections, the researchers were able to identify bite patterns of particular sizes and species of sharks by measuring jaw circumference and the distance between the six frontal teeth on the top and lower jaws, Burgess said. They experimented on 10 to 24 sets of shark jaws for each of the 14 species they analyzed. The technique works not only on human and animal tissue, but also on inanimate objects like surfboards and underground cable lines, he said.
The ability to make predictions from bite patterns is important to understanding the behavioral underpinnings of shark attacks and their prey habits, said lead researcher Dayv Lowry, a biologist with the Washington Department of Fish and Wildlife, who did the work as a graduate student at the University of South Florida.
"Often someone will send us a picture of a dolphin carcass or a sea turtle and want to know what kind of shark bit it," Lowry said. "Knowing that it's a large tiger shark, for example, would help us figure out what large tiger sharks like to eat and how they attack their prey. If an animal or person has been bitten on the rear end, then we know these sharks are likely to sneak up to get their prey instead of facing the victims."
Being able to determine what size shark attacked people in certain geographic areas such as South Africa where offshore nets are used to protect swimmers is valuable because it may influence the size mesh that is used, Lowry said. With larger sharks, beaches can get by with bigger mesh sizes, which are cheaper and less environmentally intrusive, he said.
The technique also has the potential to save thousands of dollars in damages caused by the sharks' penchant for attacking underwater electronic equipment, which includes intercontinental telephone wires, top-secret communication lines between government officials and sensors companies use to uncover oil fields, Burgess said.
Sharks are equipped with organs on the underside of their snouts -- gel filled pits called ampullae of Lorenzini -- that allow them to detect electromagnetic fields from their intended food, Burgess said. Unfortunately, sharks often do not distinguish between the signals sent by prey and equipment, which can be ruined by water seeping in through the bite marks, he said.
"That's one thing that makes them special -- they can sense electro-magnetic fields around their prey items," he said.
Laying cable lines at the bottom of the ocean is extremely expensive, and having to remove a piece, fix it and install it again adds to the cost, Burgess said. "Knowing that a certain species of shark did the damage is useful because in the future cable lines can be placed in a different location, outside the path of that particular shark's area of distribution," he said.
And the ability to determine what size shark was involved in an attack by the size and configuration of its bite marks could result in the installation of a heavier seal designed to withstand damage from that kind of shark, he said.

Shark attacks? Lottery wins more likely

Experts say there are more than 350 species of sharks in the world, and through fishing and hunting, we humans are far more of a danger to them than they are to us.But all it took was one fictitious animal to strike fear in the hearts of beach goers everywhere."Jaws. You gotta go back to Jaws. Jaws started it all," says Tom Wagner with The Florida Aquarium.In Florida, there are dozens of different types of sharks in the water. The tiger shark, the nurse shark and the black tipped shark are just a few of the most common. If you're in the water, you can be almost certain there is a shark nearby, but almost always, you'd never know it."If you live in Florida, you have a better chance of being struck by lightning four times than having contact with a shark in the wild," Wagner said.According to Florida Fish and Wildlife, there have been only 11 confirmed shark attacks in Pinellas County since 1882. You're far more likely to win the lottery, they say, than get bitten by a shark.When encounters do happen in Florida, it's often in the summer simply because there are more people in the water. The sharks most notorious for doing the biting are the black tip shark, the hammerhead and the bull shark.In 2000, a 69-year-old man died after jumping off his dock and being bitten by a bull shark. It was only the second fatality in Pinellas in the last 125 years.Wednesday, 19-year-old Jenna James was swimming just 30 feet from a dock in that same area. Emergency officials said it appears she too was bitten by a shark, though her injuries are not life threatening."Sharks don't look at people as food. So, most often what you see is a single bite, which is an exploratory bite," explains Wagner.Experts also say it's not unusual to find sharks near docks or piers. Fish generally gather around piers, and sharks go where the food is.Though encounters are rare, officials say you should always look where you're swimming and avoid swimming at dusk and dawn when sharks are most active.

Shark attack victims fight for their attackers

They may have lost fingers, or perhaps even an arm or leg, but these former surfers and vacationers paced down the halls of Congress in Washington to seek protection for sharks, their very attackers."I'm here to lobby for the bill to save the sharks, I lost my arm. It's a very powerful statement," said Al Brenneca, a 52-year-old who was attacked by a shark in 1976 in Florida.Along with a group of eight other survivors brought together by the Pew Environment Group research center, Brenneca descended on Capitol Hill to lobby senators to pass a measure placing tough restrictions on shark fishing.More than a third of all shark species are endangered, in part due to finning, a practice in which a shark's fins are cut off before the body is thrown back into the water. Shark fin soup is a beloved delicacy in Asia, where it is in high demand.Some 70 million sharks die in the ocean each year. In contrast, shark attacks on humans are rare -- between 60 and 100 per year worldwide."You might ask why considering I was attacked by a shark, why don't I want eat the sharks or kill them all?" quipped Krishna Thompson, a 44-year-old New York banker whose spectacular attack by a bull shark in 2001 during his 10-year wedding anniversary in the Bahamas had captured the media's attention.Fighting back with his bare hands, he finally freed himself from the steel-sharp jaws."I had the leg but all I could see was the femur and tibia, no skin, no vein, no muscle and I remember seeing the white bones. And I thought, 'Oh man, I'm going to be amputated,'" he recalled.Now wearing an artificial limb and a T-shirt declaring his determination to defend the shark, Thompson has converted himself into an activist fighting for the survival of the predators."What the shark did to me was what they are supposed to do," he insists. "Sharks have been around for 300 millions years -- before dinosaurs. They haven't changed much from then till now.He added that people should not mess with mother nature, and let the sharks be."I don't want find out what life would be for us as human if they ceased to exist," Thompson stressed. "If we killed all the sharks that will have an effect on us as humans. That's why I'm here."Wednesday's demonstration in the Halls of Congress was unusual and startling even for veteran lawmakers who have seem many expressions of public sentiment.All described scenes of carnage at sea when the were forced to swim in their own blood to save their lives. Most have suffered cardiac arrest by the time they arrived to the hospital.Mike Coots, 30, from Hawaii was attacked by a tiger shark in 1997 when he was surfing in the morning.The predator grabbed him by the right leg, shook him back and forth while he was trying to fight back the attacker by punching it on the head.The shark released him went back into the deep water while Mike started paddling toward the shore. But his leg was gone."I didn't feel it come off," he recalls. "It was gone. My friend took my surfing leash and made a tourniquet to stop the bleeding. Yeah. He saved my life." But Coots believes that he may have been bitten by a shark to help protect the species. "I feel very strongly that these animals have a place in the world," he insisted. "And without them, I think it's going to disrupt the entire ecosystem." But not everybody get over such life experiences. Brenneca, who lost his arm to a shark more than 30 years ago, says many people still harbor resentment toward these predators. "Some people can't get over their bite and stuff," he notes. "Some people still have an anger towards things whether it be sharks or their own stupidity. It takes years to really get over a bite like this, a serious bite where you lose your arm or you lose your leg. It takes a while to get over that."

North America's Top Shark-Attack Beaches

North America is home to dozens of beaches where swimmers and sharks intermix, even though the humans may never know it. According to George Burgess, an ichthyologist at the University of Florida who maintains a database called the International Shark Attack File. When the rare attack happens it's usually a predatory mistake. "In the surf zone, where many attacks happen, sharks need to make quick decisions," he said. "Humans on surfboards—hands splashing, feet kicking — can trigger a shark to think there's trouble or a wounded animal, and it looks like an easy meal."But according to Laleh Mohajerani, executive director of the shark conservation organization Iemanya Oceanica, sharks are not looking to interfere with humans in the water. Our shark-attack fears are irrational, she said. "You are more likely to be hit by lightning."Indeed, there's no arguing the numbers. Of the millions of people who enter the ocean each year, almost none are touched.But for most people, fiery emotions override even the coldest numbers. A single scary story — be it on the news or in an effects-heavy Hollywood production — will destroy the efforts of hundreds of scientists trying to communicate on research and logic.Take a dip if you dare.....New Smyrna Beach, Fla.Due to its thousands of annual — as well as its toothy inhabitants that hunt offshore — New Smyrna is the shark attack capital of the world. That's according to the International Shark Attack File, which cites 210 attacks in the beach's home county of Volusia, Fla. But miles of white sand and consistent surf breaks continue to draw vacationers and locals alike into New Smyrna's waters.North Shore, Oahu, HawaiiNo. 2 on the International Shark Attack File for unprovoked attacks is Oahu, where tiger sharks, Galapagos sharks and sandbar sharks congregate in high numbers, especially near beaches on the island's north shore. This doesn't stop surfers, who flock to Velzyland Beach, the Leftovers Break and dozens of additional wave-beaten beaches where sharks search and swim.Long Beach Island, N.J.Source material for "Jaws," a 1974 novel by Peter Benchley — and later a movie by Steven Spielberg — came from incidents at this New Jersey beach in 1916. In an unprecedented 11 days, five major shark attacks took place along the Jersey Shore, four of which were fatal. Reports cited blood turning the water red and sharks following victims toward the beach. Today, sharks are rare, but the legend lives on in the surf and swells of these tepid Atlantic waters.Stinson Beach, Calif.In the shadow of Marin County's Mt. Tamalpais, Stinson Beach is a spot where great white sharks swim into the shallows. Patric Douglas, owner of Shark Diver, an ocean guiding outfit in San Francisco, said he has sighted them at Stinson — which is a neighboring stretch of sand east from Bolinas Beach (No. 3 on the list)— in less than 20 feet of water. "They're coming to feed on seals, though it's not uncommon for surfers to see them," he said.Beaches of Brevard County, Fla.In the past 100 years, there have been 90 reported shark confrontations on beaches in this county on Florida's east coast. Visitors head east from Orlando to the ocean to dip toes in the tepid waters at Cocoa Beach, Jetty Park and Klondike Beach, a 24-mile-long wilderness beach accessible only by foot in Canaveral National Seashore preserve.Horry County, S.C.South Carolina has seen more than 50 total shark attacks over the past century, according to the International Shark Attack File. Of those, 16 attacks are recorded off the beaches of Horry County, where the town of Myrtle Beach is famous as a tourist destination. The good news: The International Shark Attack File cites no fatal shark attacks in South Carolina since 1852.Solana Beach, Calif.A freak great-white attack in 2008 at Solana Beach in San Diego County, Calif., killed a 66-year-old swimmer. He was on a morning swim, training with a group when the attack occurred. Solana Beach, home to a population of seals, is at the periphery of the corridor where great sharks commonly roam.

Cage-diving tours found not to increase shark risk

There is no scientific evidence that Oahu North Shore cage-diving tours increase shark attack risk for recreational ocean users in near-shore waters, a two-year study of shark behavior concluded.Scientists from the Hawaii Institute of Marine Biology noted a lack of proof during the latest shark tour debate, said biologist Carl Meyer.Meyer, who represented the scientists, presented data from the study, which focused on public safety concerning the North Shore shark cage-diving tours, at an informational briefing at the state Capitol last night.About 50 people attended the meeting. It was quiet compared with the confrontational one held in Hawaii Kai on April 16, with many opposed to a Hawaii Kai man's plan to start a shark cage-diving tour in Maunalua Bay. The man has abandoned the plan.Such shark tours pose no significant threat to near-shore ocean recreation users, and there is no reason to believe they will as long as they remain "spatially separated from recreational ocean users," Meyer said in response to a question on whether the data might shift if there is an increase in the number of tour operators on the South Shore.Meyer noted other studies that show a greater number of attacks were in connection with shark tours that involved an operation with underwater divers who sit on the reef and attract sharks with fish parts versus cage-diving tours.He also noted that 40 years of crab fishing in the area, which involves dumping old bait, has preconditioned the sharks and produced the same phenomenon."As a biologist, I would be concerned if they would go into a pristine area," he said.State Sen. Mike Gabbard (D, Kalaeloa-Makakilo) said a Florida study showed shark tours lead to negative interaction of sharks with people because sharks become accustomed to the sound of boats and expect a free meal.Meyer said the sharks appear to respond only to the tour boats and not to other boats.Billy Robello, a recreational fisherman, disagreed, saying in Maunalua Bay sharks would swarm around his boat in an area he believed had been baited with fish parts

Sharks pose Sydney food-chain puzzle

Three shark attacks in Sydney in three weeks drove newspapers and talk show hosts into a feeding frenzy and sent a collective shudder through the other species at the top of the food chain -- humans.There was fierce debate about why there had been so many attacks -- a total of seven around the country in just three months -- and calls for shark conservation measures to be lifted.Although all three Sydney victims survived, two of them lost limbs and one of the attacks in particular drew close attention.As the first light of dawn filters over hills lined with multimillion-dollar mansions and classy seafood restaurants, the surface of the bay shatters into dancing shards of silver.Flyfishing guide Justin Duggan cuts the motor and lets the small boat drift as a client snakes a line out in search of predators feeding on the tiny skipping fish massed in a suburb of Australia's biggest city.They are Australian anchovies, near the bottom of a food-chain boom bringing Sydney Harbour roaring back to life, delighting environmentalists and fishermen and making resident fairy penguins fat.But at the top of the chain are the toothy killers that have been the talk of the town this southern hemisphere summer -- sharks.On February 11, a navy diver was mauled by a bull shark in Sydney Harbour, not far from the famous Opera House, suffering serious injuries that later forced doctors to amputate an arm and a leg.While shark attacks are not uncommon off Australia's vast coastline, experts said no one had been bitten by a shark in Sydney Harbour for more than a decade and the last fatal attack was in 1963."The harbour is so full of baitfish -- that's why there are so many predators around," says Duggan, a fishing guide for seven years. "It's a protein soup."Duggan attributes the baitfish boom and the increase in predators -- which themselves attract sharks -- to a ban on commercial fishing in the harbour in 2005 and anti-pollution measures producing cleaner waters."Fish like (Australian) salmon and kingfish like cleaner water," he says, pointing out to his client, retired surgeon David Hunt, another pelagic species -- frigate mackerel -- slicing the surface."I've seen schooling kingfish under the harbour bridge, and I've certainly seen more sharks this year. We are also just getting reports left, right and centre of people seeing sharks," he said.Duggan is cautious about the shark scare, however, complaining that hysteria over attacks ignores the fact that people have more chance of being killed in a car while travelling to the beach than they do while swimming."It's arrogant to say that sharks should be culled just because of a few attacks on humans -- people have to take their chance when they go into the water," he said.That attitude was shared by at least one recent shark victim, avid diver and fisherman Brian Guest, 51, who disappeared in a frenzy of fins and blood off a Western Australia beach in December.Nothing was found of him except shreds from a wetsuit, but a fishing website still carried his words: "I have always had an understanding with my wife that if a shark or ocean accident caused my death then so be it."Guest also made clear his opposition to the idea that sharks should be killed to reduce the risk to swimmers. Duggan starts the motor and heads out of the bay, sliding past upmarket suburban homes and under a bridge carrying dense commuter traffic to work. The surface of the water erupts again just after the bridge, as cormorants, gulls and pelicans herd baitfish into the shallows for a wild feast. "Look," said Duggan, pointing to four small creatures swimming a little further on. "Those are the fattest fairy penguins I've ever seen." Sydney's harbour is a vast and beautiful stretch of open water, bays, beaches and islands, lined by some of the most expensive real estate in the world. It is a great setting for restaurants where residents dine on fresh seafood -- and an unlikely setting for modern humans to face being eaten by prehistoric creatures. The attack on the diver took place near Garden Island in Wolloomooloo Bay, which hosts a popular strip of expensive eateries and celebrity apartments. But diners concerned about seafood exacting revenge can take comfort from shark expert John West of Sydney's Taronga Zoo. "Humans are not part of the shark's diet, otherwise there would be nobody safe in the water," he told AFP. And even the most feared of predators, the great white shark, doesn't like the taste of humans, an official said in an apparent attempt to reassure swimmers after an attack at Sydney's Bondi Beach in February. "Note that in almost all cases, great whites tend to release the person after biting -- probably as they don't recognise the taste," said New South Wales Primary Industries Minister Ian Macdonald. A total of 194 deaths through shark attacks have been recorded in Australia over the past two centuries, leading researchers to point out endlessly that more people die from bee stings and lightning strikes. But there is something about being eaten that resonates with humans -- and gave pause to diners at Wooloomooloo, at least for a few weeks this summer.

Shark Attacks Decline Worldwide In Midst Of Economic Recession

The recession may be responsible for a slump of a different sort: an unexpected dive in shark attacks, says a University of Florida researcher.Shark attacks worldwide in 2008 dipped to their lowest level in five years, a sign that Americans may be forgoing vacation trips to the beach, said George Burgess, ichthyologist and director of the International Shark Attack File, which is housed at UF.According to the latest statistics released February 18, the total number of shark attacks declined from 71 in 2007 to 59 in 2008, the fewest since 2003, when there were 57, said Burgess, who works at the Florida Museum of Natural History on the UF campus."I can't help but think that contributing to that reduction may have been the reticence of some people to take holidays and go to the beach for economic reasons," Burgess said. "We noticed similar declines during the recession that followed the events of 2001, despite the fact that human populations continued to rise."Shark attacks dropped in the United States and abroad in 2008, Burgess said. In recent years, vacationing tourists have been attacked off beaches in remote parts of the globe, such as Cocos Island in the Indian Ocean, where none was reported in the past, he said.There were four fatal attacks last year — an average number — compared with only one in 2007, which marked a two-decade low. Two of the deaths were in Mexico, one was in Australia and one was in the United States.La Niña, a meteorological condition that brings water masses and deep ocean creatures closer to shore, probably was a factor in the deaths of two male surfers and injury of a third that occurred in less than a month along a resort-studded stretch of Mexico's southern Pacific coast, Burgess said. The U.S. fatality was a 66-year-old man swimming at Solana Beach, Calif., while the Australian death occurred along the country's eastern coast and involved a 16-year-old boy.The number of shark attacks in the United States, which typically makes up about two-thirds of the total worldwide, dropped from 50 in 2007 to 41 in 2008, Burgess said. Thirty-two of those attacks were in Florida — the same number as the previous year — followed by North Carolina and South Carolina, with three each; Hawaii, two; and California, one.Florida, with its warm waters, has more sharks, including black tip sharks and spinner sharks, species not found in lower temperatures, Burgess said. "A lot less attacks occur off Long Island, New York, than Florida simply because there are fewer sharks up there," he said.Within Florida, Volusia County continued its dubious distinction as the world's shark bite capital with 22 incidents, its highest yearly total since 2001, Burgess said. Attractive waves off New Smyrna Beach on the central Atlantic coast are popular with surfers, he said.As in past years, surfers accounted for most of the world's attacks —57 percent — followed by swimmers and waders, 36 percent; and divers, 8 percent, he said. These numbers are rounded up, which is why they total more than 100 percent."Surfers are the heavy favorites largely because the splashing of arms and particularly the kicking of feet at the water's surface where visibility is poor is provocative to sharks," Burgess said. "They result in what we think are cases of mistaken identity, where the shark interprets the irregular splashing to be activities of its normal prey."As a group, surfers seem to accept the risks of pursuing a sport in the ocean, he said."I've yet to find a surfer who says he or she won't go back into the water after a bite or a nip," he said. `Some of them may be looking over their shoulders a little bit more than they did before, but the reality is they understand where humans fall in the grand order of things."Burgess said he doubts the economic recession is likely to deter surfers because their interest in the recreational activity is so high. "It's oftentimes not a group that is economically blessed, but all they have to do is drive to the beach with the board and get into the water, and the rest is free," he said.To a certain extent, divers, like surfers, pursue their sport as something of an avocation, leaving swimmers and waders as the group most likely to be affected by economic hardship, Burgess said. "These are sort of the average folks that go to the water for recreation, lie on the beach, work on their suntan and take their kids in the surf for a swim," he said. "I would expect their numbers to decline in 2009."Over the long term, though, Burgess expects shark attacks to rise because of a gradual upswing from one decade to the next. "We've already surpassed the numbers of attacks in the previous 10-year period," he said, "so we know this decade will be higher than the last."Source: University of Florida.

Australian shark attack diver to lose leg

An Australian navy diver who fought off a shark in a rare attack in Sydney Harbour was due to undergo surgery Wednesday to amputate his leg.Able Seaman Paul de Gelder, 31, was taking part in a defence exercise near an upmarket residential area of the harbour in Australia's largest city when he was attacked last week, losing his right hand."I will today have my right leg amputated," de Gelder said in a statement on Wednesday."The past week has been quite an overwhelming experience and without certain people I definitely wouldn't be alive today."De Gelder thanked the three colleagues who pulled him from the jaws of the three-metre bull shark, and the paramedics and doctors who treated him."I'm looking forward to rebuilding my life and taking on the new challenges I have to face," he said."Ultimately I would like to return to what I love - Navy diving."The attack took place near the Garden Island Naval Base in Woolloomooloo Bay, which is lined with seafood restaurants and celebrity apartments.While shark attacks are not uncommon off Australia's vast coastline, experts said no one had been bitten by a shark in Sydney Harbour for more than a decade and the last fatal attack was in 1963.The diver's mauling follows a spate of attacks on swimmers off Australian beaches last month, unnerving summer holidaymakers. Three swimmers were attacked and injured within 24 hours just two weeks after a snorkeller was killed.But, with 194 deaths through shark attacks recorded in Australia over the past two centuries, researchers point out endlessly that more people die from bee stings and lightning strikes.

Surfer injured in second Sydney shark attack

Australia's most famous beach reopened Friday, hours after a surfer's arm was shredded by a shark — the second shark attack in Sydney in as many days.The 33-year-old man, whose name was not released, was bitten Thursday around dusk at Sydney's popular Bondi Beach and suffered severe arm injuries, police said. Other surfers helped him to shore, where volunteers helped to stop his bleeding.The man underwent a 10-hour surgery at St. Vincent's Hospital, and was in serious but stable condition Friday, hospital spokesman David Faktor said."We could see all of his bones cut like with a big knife. It was very clear," French tourist Mikael Thomas, 21, told Australia's Fairfax Media.Lifeguards sounded the beach's shark alarm and cleared the water. Surfer James McIntosh, 29, said he tied a leg rope around the victim's arm as a tourniquet."I just kept pulling that leg rope as hard as I could. As soon as we put the tourniquet on there wasn't any bleeding," he told Fairfax.On Wednesday, a Navy diver lost his hand after fighting off a shark in Sydney Harbour, not far from the Opera House. His leg was also badly mauled.A recent string of shark attacks across Australia has left some swimmers jittery. In December, 51-year-old Brian Guest vanished while snorkeling with his son off a beach in Western Australia. A piece of his wet suit was later found, and officials said he was almost certainly eaten by a shark.Last month, a 13-year-old surfer in the island state of Tasmania was dragged under water by a 16-foot (5-meter) great white shark, and a 31-year-old surfer was bitten while surfing at a remote beach in New South Wales state the same day. Both survived.The following day, a shark latched onto the leg of a snorkeler in southern New South Wales. The man survived after pummeling the creature with his fists until the shark let go.Most experts agree the cluster of attacks is a freak coincidence and say there is no evidence of an increase in the country's shark population. Nevertheless, some have argued that cleaner, nutrient-rich waters have boosted the animals' reproduction and drawn them into shallow waters.Although sharks are often spotted off Australia's beaches, fatal attacks are rare. On average, just one person is killed by a shark in Australia each year, according to the Australian Shark Attack File database.

Shark attacks surfer at Australia's Bondi Beach

A shark attacked a surfer at Sydney's famous Bondi Beach Thursday, seriously injuring the man's left hand and arm, Australian police said.There has not been a shark attack at Bondi for decades.The attack comes one day after a navy diver was attacked by a shark in Sydney Harbor. The diver lost a hand and has severe leg injuries.The shark attacked the 23-year-old surfer just before dark."He said he felt a tug on his arm. When he looked down he saw a bad bite on his left hand and arm," a police spokesman said."He yelled for help and nearby surfers assisted him. Some off-duty doctors on the beach helped stem the bleeding."There have been at least four other shark attacks so far this Australian summer, one of them fatal, sparking a global media frenzy of "Jaws" proportions. Last month, there were three shark attacks in Australian waters in just two days.The last fatal attack at Bondi was in 1929.Wildlife officials say Sydney's cleaner ocean water, due to offshore sewage outlets and stormwater cages, has encouraged marine life closer to shore, which in turn has attracted sharks.Wednesday, the navy diver punched a shark as he was being attacked in Sydney Harbor, fending off the predator but suffering severe injuries to his right hand and leg. Shark nets are used off all of Sydney's ocean beaches.They are rectangular pieces of net suspended in the water between buoys. When sharks get caught in the nets they drown.The nets are not intended to form a complete barrier and sharks can still get through. The nets act as a deterrent by interrupting the territorial swimming patterns of sharks.

Sharks, not humans, most at risk in ocean

Three shark attacks in Australia in two days this week sparked a global media frenzy of "Jaws" proportions, but sharks are more at risk in the ocean than humans with man killing millions of sharks each year.Sharks are the top of the marine food chain, a powerful predator which has no match in its watery realm, until man enters the ocean.Commercial fishing and a desire for Asian shark fin soup sees up to 100 million sharks, even protected endangered species of sharks, slaughtered around the world each year, says the Shark Research Institute (Australia).Yet in contrast, sharks, apparently, do not like the taste of humans. Very few shark attacks involve the shark actually eating the human, unlike a land-based predator like a lion or tiger."Most of the incidents in the (Florida-based) global shark attack file have nothing to do with predation," says the Institute on its website (www.auscyber.net).Unlike fat seals -- the preferred meal of sharks like the Great White -- humans are bony with not much fat. Sharks use various sensors to hunt their prey and a quick bite will tell it whether its found a good meal.Usually when a shark bites a human it then swims off. Unfortunately for humans, sharks are big and we are small, so a large shark bite can mean death from rapid loss of blood."Sharks are opportunistic feeders. They hear us in the water, we sound like a thrashing fish or animal in the water, and they just react to that instinctively and go to take a bite," marine analyst Greg Pickering told local radio on Wednesday.According to the latest figures by the International Shark Attack File, there was only one fatal shark attack in 2007. It took place in New Caledonia in the South Pacific. The mean number of deaths between 2000 and 2007 was 5 a year."You have more chance of being killed driving to the beach," said John West, curator of the Australian Shark Attack File at Sydney's Taronga Zoo.In fact, the number of fatal attacks around the world has been falling during the 20th century, due to advances in beach safety, medical treatment and public awareness of shark habitats.The bulk of shark attacks do not happen in Australian waters, despite its shark reputation, but in North American waters. Half of the world's shark attacks occur in the United States, and one third of the world's attacks are in Florida waters.In 2007, there were 50 shark attacks in U.S. waters, compared with 13 in Australia in the same year -- none were fatal.The big difference between Florida and Australia is that the later has much bigger sharks and therefore more fatal attacks. From 1990 to 2007, Australia had 19 fatal attacks, Florida 4.But there have only been a total of 56 fatal shark attacks in Australia in the past 50 years, or an average of about 1 a year, says the Australian Shark Attack File.The last fatal attack occurred in December 2008, when a Great White attacked a 51-year-old man while he was snorkeling off a beach south of Perth in Western Australia.So, is it safe to go back in the water?Shark attacks are on the rise worldwide, but according to the International Shark Attack File, that doesn't mean there is an increased rate of shark attacks. "As the world population continues its upsurge and interest in aquatic recreation concurrently rises, we realistically should expect increases in the number of shark attacks," says the file on its website (www.flmnh.ufl.edu). SHARKS IN DECLINE But while more humans enter the ocean each year and for longer periods of time, the shark population is declining, theoretically reducing the chances of a shark-human encounter. "As a result, short-term trends in the number of shark attacks, up or down, must be viewed with caution," says the file. So, if shark numbers are falling why are there more sightings of sharks off Australia's beaches. Surfwatch Australia, which conducts aerial patrols of Sydney beaches, estimates shark sightings have risen 50 to 80 percent in recent years. Wildlife officials say cleaner beach water means sharks are chasing food closer to shore. Sydney beaches were closed this month when hammerheads started feeding on squid near swimmers. But only about two dozen shark species are considered potentially dangerous to humans because of their size and teeth. The Great White, Bull, Tiger and Hammerhead are among the most aggressive and responsible for most attacks in Australia. The Great White can grow to 5.5 meters (15 feet) in length, weigh up to 1,000kg and has the biting power to lift a car. Australian scientists have recorded the bite power of a 3.2 meter (10 foot) shark as equivalent to 1.5 tonnes of pressure. The aggressive looking Grey Nurse, with its piercing eyes, pointy nose and protruding teeth, is as timid as a cat and will only attack if provoked. But its fierce appearance has seen it hunted to the point where it is now endangered and colonies of Grey Nurse sharks off Sydney are protected. There are 30 sharks, including the Great White, on the International Union for Conservation of Nature's threatened species list. "Sharks need our help now and we cannot let our fear push them to the brink of extinction," says Ben Birt, from Australia's Nature Conservation Council, which has launched a "Save Our Last Sharks" campaign.

Sharks have wimpy bites

Sharks have wimpy bites for their size and can crunch through their prey only because they have very sharp teeth -- and because they can grow to be so big, researchers reported on Tuesday.Their studies of shark jaws show that lions or tigers win hands down when it comes to jaw strength -- but sharks prevail in the water because of their wide jaw size."Pound for pound, sharks don't bite all that hard," Daniel Huber of the University of Tampa in Florida, who led the study, said in a telephone interview.Huber and colleagues had trouble collecting data for their study, "due to the experimental intractability of these animals," they wrote dryly in their report, published in Physiological and Biochemical Zoology."The vast majority of the data that went into this study was biomechanical models," Huber said.They also measured the bites of small sharks such as sand sharks, and tested larger sharks by knocking them out and using electricity to stimulate the jaw muscles.Their conclusions? Sharks can do a lot of damage simply because their teeth are so sharp and their jaws are so wide."Our analyses show that large sharks do not bite hard for their body size, but they generally have larger heads," they wrote.A 20-foot (6-meter) great white shark can "bite through anything that you come across," he adds.Many must use a sawing motion to break apart their prey, said Huber, whose team studied 10 different species of shark. Mammals have evolved much more efficient jaw muscles, he noted.

Famed shark fisherman Frank Mundus dies, was 82

Frank Mundus, the legendary shark fisherman said to have inspired the Captain Quint character in the movie "Jaws," has died. He was 82.
Mundus died Wednesday at The Queen's Medical Center in Honolulu after a heart attack, his wife said.
It was his second heart attack in four days. He suffered the earlier one Sept. 6 at Kona International Airport after returning from a business trip to New York.
Mundus had a history of heart disease, his wife, Jeanette Mundus, 46, said from their home in Naalehu on the southern tip of the Big Island. He suffered his first heart attack in 1998 and later had quadruple bypass surgery.
Known as the "Monster Man" for the size of the sharks he caught, the gregarious Mundus had an outsized personality nearly as big as his famed boat, the Cricket II.
He forged his reputation as a fearless fisherman in Montauk beginning in 1951, hunting down the world's biggest sharks.
"I had a lot of close calls," he once said. "Probably too many close calls."
In 1964, Mundus used a harpoon to snag a 4,500-pound great white. He later bagged a 17-foot-long, 3,427-pound great white by rod and reel in 1986. He later described the experience to Esquire magazine.
"After you get the fish, you turn around and look at the fish, and you feel sorry for the fish because he's your opponent," Mundus recalled. "I always feel good that I won, but I feel sorry for the one who lost."
On his Web site, Mundus said events from the 1964 catch influenced Peter Benchley, who wrote "Jaws." But Benchley maintained that Quint was a composite character.
The best-selling book was turned into the 1975 film, a blockbuster that left many beachgoers thinking twice about taking a dip in the ocean.
Mundus, who was born in Long Branch, N.J. in 1925, called "Jaws" the "funniest and the stupidest" movie he had ever seen and said he some things in common with Quint such as similar fishing techniques.
Jeanette Mundus said her husband actively promoted shark conservation starting in the 1960s. He pushed the use of less damaging hook varieties that allow fishermen to catch and release the fish.
"A lot of people over the years have thought of him just as a hunter of sharks," Jeanette Mundus said. "But he did try to preserve them."
Mundus retired to Hawaii in 1991 after a lifetime of fishing. He didn't regularly fish for sharks off Hawaii, his wife said.Andrew WilsonDirectorUnder the Seahttp://www.touchthesea.org

Mexico to tag sharks after deadly attacks

Biologists in Mexico plan to tag hundreds of sharks off the Pacific Coast to help understand the cause of a rare spate of deadly attacks on humans, the local government said on Tuesday.Sharks near the southwestern resort of Ixtapa-Zihuatanejo killed two surfers and maimed another in the past few weeks, the first fatal shark attacks along Mexico's Pacific coast in 30 years, according to official records.Biologists plan to tag sharks and ask fisherman to look out for them and report back on their movements, Guerrero state Environment Secretary Sabas Arturo de la Rosa told Reuters.A smaller group of sharks will be tagged with electronic devices that would transmit data on their behavior and locations to biologists via radio frequencies, he said.The tagging is expected to begin in about two months and the study should last a year."We need to get to the 'why' these animals are coming so close to Guerrero's shores, which is so unusual," De la Rosa said.Shark experts believe unusually cool sea-surface temperatures could be partly responsible for the attacks, but they also note that a dearth of data about sharks in the region makes it difficult to reach conclusions.The researchers plan to use a special baited fishing line to catch sharks in the area and then tag and release them, said Jose Leonardo Castillo, a shark expert with the National Fishing Institute who is involved with the project.Fishermen who come across tagged sharks will be compensated for reporting their location, Castillo said.More expensive telemetric tags on a smaller number of sharks will emit radio frequencies that scientists can track.Surfer Bruce Grimes from Texas recently became the third person to be bitten by a shark since late April. Grimes survived the attack but needed 100 stitches in his arm.

Mexico Navy hunts for sharks after attacks

The Mexican Navy searched for sharks in the ocean near Pacific surfing beaches on Monday, after two bathers were killed and another maimed in a rare spate of shark attacks. Three boats and a helicopter patrolled the sea while Navy and rescue officials scanned the horizon with binoculars from popular beaches around the southwestern Mexican resort of Ixtapa-Zihuatanejo. They warned surfers not to go far out."We've been monitoring the beaches; we've done reconnaissance flights," Rear Adm. Arturo Bernal said, adding that no big shark had been detected yet in the area.Surfer Bruce Grimes from Texas was bitten on the arm on Saturday off nearby Playa Linda beach, making him the third target of a shark attack in the area in a month.Two attacks in April and May killed a Mexican and an American -- the first shark deaths off Mexico's Pacific coast in 30 years, according to official records.Grimes, 49, said he paddled madly toward shore on his board after feeling the unmistakable sandy skin of a shark glide across the bottom of his feet as he straddled his surfboard."Then it bumped me really hard. I thought, 'That's definitely a big shark.' I took about three more strokes and he grabbed my arm," said Grimes, who pulled himself free and made it to the beach. He managed to drive himself to a hospital, where he received 100 stitches.On Friday, Mexican surfer Osvaldo Mata, 21, died after a 6-foot-long (2-m-long) shark seized him, bit off one of his hands and chomped on his thigh. That followed the death in late April of a 24-year-old American who was mauled while surfing nearby.The Ixtapa-Zihuatanejo government is consulting with experts to determine what could be causing the attacks.

Human deaths from shark attacks hit 20-year low last year

Fatal shark attacks worldwide dipped to their lowest levels in two decades in 2007 with the sole casualty involving a swimmer vacationing in the South Pacific, according to the latest statistics from the University of Florida.Except for 1987, when there were no fatalities, the last year a single human death occurred from a shark attack was in 1985, said George Burgess, director of the International Shark Attack File housed at UF's Florida Museum of Natural History. By comparison, there were four deaths each in 2005 and 2006, and seven in 2004."It's quite spectacular that for the hundreds of millions of people worldwide spending hundreds of millions of hours in the water in activities that are often very provocative to sharks, such as surfing, there is only one incident resulting in a fatality," he said. "The danger of a shark attack stays in the forefront of our psyches because of it being drilled into our brain for the last 30 years by the popular media, movies, books and television, but in reality the chances of dying from one are infinitesimal."Advances in medical treatment, greater attention to beach safety practices and increased public awareness about the danger of shark attacks are all likely reasons the fatality rate so far for the 21st century, at 7.6 percent, has been lower than the 12.3 percent recorded for the 1990s, Burgess said.The number of shark attacks overall increased from 63 in 2006 to 71 in 2007, continuing a gradual upswing during the past four years, he said."One would expect there to be more shark attacks each year than the previous year simply because there are more people entering the water," he said. "For baby boomers and earlier generations, going to the beach was basically an exercise in working on your suntan where a swim often meant a quick dunking. Today people are engaged in surfing, diving, boogie boarding and other aquatic activities that put them much closer to sharks."Occasionally, the number of attacks may drop in a particular year because of changes in meteorological or oceanographic conditions that affect water temperature and salinity, such as the frequency of hurricanes and tropical storms, Burgess said. But scientists don't put too much stock in these year-to-year fluctuations, preferring to look at long-term trends, he said.Traditionally, about half of the world's attacks occur in United States mainland and Hawaiian waters, but the proportion was greater in 2007, Burgess said. Last year's total of 50 attacks returned to 2000 and 2001 levels of 53 and 50, respectively, after dropping from 30 to 40 for each year between 2003 and 2006, he said.Elsewhere, there were 12 attacks in Australia, up from seven in 2006 and 10 in 2005, but down slightly from the 13 attacks recorded in 2004. There were two attacks each last year in South Africa and New Caledonia, with single incidents reported in Fiji, Ecuador, Mexico and New Zealand.There also was an upswing in attacks along the Florida coast, jumping from 23 in 2006 to 32 in 2007. There has been a gradual increase in human-shark skirmishes in the Sunshine State since they dropped from 37 in 2000 to an 11-year-low of 12 in 2004, he said.Within Florida, Volusia County continued its dubious distinction as the world's shark bite capital with 17 incidents, its highest yearly total since 2002, Burgess said. Attractive waves off New Smyrna Beach on the central Atlantic coast are popular with surfers, he said.Additional U.S. attacks were recorded in Hawaii - seven - marking a five-year-high, along with South Carolina, five; California, three; North Carolina, two; and Texas, one.Fifty-six percent of the 2007 victims were surfers and windsurfers; followed by swimmers and waders, 38 percent; and divers and snorkelers, 6 percent.Last year's Sept. 30 fatal attack involved a 23-year-old woman from France who was snorkeling off the Loyalty Islands archipelago in French New Caledonia and became separated from a friend, Burgess said. She was a nurse who had just finished a hospital contract in Noumea and was taking a brief vacation before flying home, he said."We advise not getting yourself isolated because there is safety in numbers," he said. "Sharks, like all predators, tend to go after solitary individuals, the weak and the infirm, and are less likely to attack people or fish in groups."Last year had few spectacular attacks or heartwarming rescue stories, Burgess said. "It was mostly minor injuries," he said. "There weren't too many made-for-movie moments."University of Florida