After Roaming the Seas for 400 Million Years, Sharks Are Now Facing Their First Real Threat--Humans.

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1 Home Back My Research Educators' Resources Toolbox Log-out X Help How to Cite Dictionary Thesaurus BLUE PLANET QUARTERLY Summer 2002, pp Copyright 2002, BLUE PLANET QUARTERLY. All rights reserved. Reprinted with permission. Sharks Under Attack After Roaming the Seas for 400 Million Years, Sharks Are Now Facing Their First Real Threat--Humans. By Sara Bennington Heather Hale knows exactly when she started fearing sharks. She was eight years old, watching Jaws, the horror film about a man-eating great white. Living in upstate New York, Hale, a World Cup rugby player, was petrified of being attacked by a shark. "I was even afraid to swim in the local lake," she admits. Moving to Virginia Beach as a teenager didn't help quell her fear. "I really didn't enjoy the beach. I was too worried about sharks:" It wasn't until a snorkeling trip to Australia's Great Barrier Reef l0 years later that her fears began to subside. During the dive, Hale and her instructor happened upon a whitetip reef shark. Initially panicked, she relaxed as she realized the shark wasn't trying to make her its lunch. "The shark swam by and then went on its way," she says. "It wasn't even interested in me." While Hale admits that she's far from conquered her fear of sharks, she does have a new perspective on the fish and their reputation as "man-eaters" after her encounter. Heather Hale's story is a fairly common one. She is one of the many people who fear sharks more than they do more common (and deadlier) dangers such as dogs, pigs, and drowning. But not everyone can counter these anxieties with a positive experience. Worse, the widespread fear of sharks is contributing to their demise. Combined with troubling practices such as overfishing, finning, bycatch, and lack of management, human fear, contempt, and ignorance are clamping down on "Jaws." Why Sharks are Important Sharks have roamed the seas for 400 million years, thriving while other species became extinct. As elasmobranchs (sharks, skates, and rays), they are an interesting evolutionary exception, having remained virtually unchanged for the last 70 million years. Sharks are also vital to healthy oceans. Most are apex predators, playing a crucial role in keeping ocean ecosystems in balance by singling out weak and sick prey. Sharks can also offer important insights into biomedical research. Thanks to remarkable immune systems, they are highly resistant to cancer and may hold the key to a better understanding of fighting the disease in humans. Sharks are also a public resource that should be protected for the benefits of future generations. Facing Numerous Threats Despite their terrifying reputation, sharks are some of the most vulnerable creatures in the sea. Their life history characteristics make them particularly vulnerable to an array of increased pressures, as populations can be quickly depleted and take decades to recover. 1 of 5 12/31/69 7:23 PM

2 Overfishing Many shark populations around the world have declined dramatically in recent decades. Overfishing is the principal culprit in the precipitous decline. Sharks' biological vulnerabilities--their late sexual maturation and low reproductive rates--don't allow species to quickly recoup losses incurred from fishing. Quite simply, sharks are being taken out of the ocean faster than they can reproduce. According to Dr. Jack Musick, head of the Shark Research Program at the Virginia Institute of Marine Science and co-chair of the World Conservation Union's (IUCN) Shark Specialist Group, the large coastal sharks in the U.S. Atlantic in particular have suffered greatly from overfishing. "Once an abundant species found in the western Atlantic Ocean, the sandbar shark declined by approximately 80 percent between the 1970s and the mid-to late-1990s due to overfishing," Musick explains. Dusky sharks are another large coastal species that has experienced enough depletion in the last 30 years to warrant a prohibition on fishing. Restoring the population will be difficult. According to Musick, dusky females aren't sexually mature until age 20, and they may only reproduce every third year. The species is now considered a candidate for listing under the Endangered Species Act (ESA). Sonja Fordham, shark specialist and Fish Conservation Project Manager for The Ocean Conservancy, is also concerned about the dusky's recovery. "Despite protection, these exceptionally vulnerable creatures continue to be caught and killed as bycatch in the Atlantic large coastal shark fishery," she says. Alan Henningsen is a shark biologist and senior aquarist research associate with the National Aquarium in Baltimore. "Sharks have been around for hundreds of millions of years, and in a short amount of time we have come close to completely destroying them," he laments. He lists several species--dogfish, basking, and soupfin--that have been fished to the point of collapse as evidence that overfishing is a serious problem. "There are few, if any, sustainable directed shark fisheries," he says. "In many cases, the populations were rapidly depleted to the point where the fisheries collapsed." Henningsen is currently working on the Cooperative Shark Tagging Program run by the National Marine Fisheries Service's (NMFS) Apex Predator Investigation Group. The program maintains sandbars for education, to study growth, and for tagging purposes. "There are some signs that the sandbar is coming back, but it will take several decades before it happens." That's the problem with overfishing; species can be depleted in only a few years, but require decades to fully recover. Bycatch Unfortunately, not all the sharks fishermen catch are the intended prey. In fact, bycatch--animals caught incidentally along with the targeted species--claims the majority of sharks around the world. There is little doubt among the conservation community that overfishing and bycatch are some of the greatest threats to sharks today. "It is well documented that we have a large impact on sharks through commercial fishing, either targeted or bycatch," says Dr. Colin Simpfendorfer, an Australian shark biologist and staff scientist at the Mote Marine Lab in Sarasota, Florida. Finning Many of the sharks caught as bycatch fall victim to finning---the particularly distasteful practice of slicing off a shark's fins and tossing its dead or dying carcass back into the ocean--and others are also targeted just for their fins. Shark conservationists decry this practice."finning is terribly wasteful," insists Fordham. Still, the shark fin market is incredibly lucrative and flourishing. Highly prized for use in the traditional Asian delicacy "shark fin soup," some fins retail for $200 per pound. As a result, shark finning in Hawaiian waters exploded in the 1990s. In 1991, only three percent of sharks were killed solely for their fins; in 1998, that figure had rocketed to 61 percent. Nearly 60,000 sharks--mostly blue sharks--were killed that year for their fins. Conservationists hope new regulations will help ease the pressure on sharks caught for their fins, at least in U.S. waters. In 2000, Congress enacted the Shark Finning Prohibition Act to prohibit the 2 of 5 12/31/69 7:23 PM

3 practice of shark finning in all U.S. federal waters. In February 2002, NMFS published final regulations to implement the Act. In addition to the practice of finning, the regulations also prohibit ships from landing shark fins without the corresponding carcasses. The new rules do not generally apply in state waters or to foreign boats outside the U.S. 200-mile limit. While pleased with the regulations, shark conservationists say the fight is not over--finning is still legal in most oceans around the globe. "To really have teeth, the federal law must be used as a springboard for international agreements to protect highly migratory shark species," argues Fordham. Managing Sharks? But finning, overfishing, arid bycatch are just symptoms of a larger problem: the lack of effective management plans designed to conserve shark populations. Currently, there is no international management for sharks. The United States is one of only a few major shark-fishing nations that regulates shark fishing. In the 1980s, Atlantic shark fisheries expanded rapidly as shark meat was marketed as an alternative to tuna and swordfish, depleting many shark populations. It wasn't until 1993 that NMFS implemented an Atlantic shark management plan, grouping 39 shark species into three categories: large coastal, small coastal, and pelagic (open ocean). The plan, administered by NMFS, also banned finning and set commercial and recreational catch limits. Its goal was to prevent overfishing to help rebuild and sustain the shark populations. In 1998, management of all federal fisheries for Atlantic sharks (except dogfish) was moved under the Highly Migratory Species Fishery Management Plan for Atlantic tuna, swordfish, and sharks. But even U.S. regulations do not guarantee good shark management, as the plan has fallen far short of its goal. In June 2001, The Ocean Conservancy brought a lawsuit against the federal government to stop overfishing of large coastal sharks. The plaintiffs charge NMFS with succumbing to commercial fishing pressures and failing to halt the overfishing and rebuilding of large coastal shark populations. They also claim that NMFS illegally left public comment and participation out of the fisheries management process and allowed outside parties to make key management decisions. A ruling is expected later this year. Research is one element shark biologists advocate to improve shark management. According to Greg Skomal, a marine fisheries biologist and shark researcher for the State of Massachusetts, sharks will always be a fisheries resource, and shark fisheries need to evolve as they learn more about these animals. "We need to identify the holes in the data, fill those holes, and manage fisheries so it's win-win all around," says Skomal. "In the meantime," he adds, "shark management should take the precautionary approach." Despite worldwide increases in shark catch, only a few countries have developed management programs for sharks. Many that do exist are proving inadequate in halting population declines. "Sharks don't recognize international boundaries," says Fordham. "Shark fishing nations need to work together to conserve the sharks they share." Musick agrees, "We must recognize that there's a problem with management on a global scale, which is difficult. Then we must get nations to enact regulations." Due to growing recognition of the situation, a United Nations body adopted an International Plan of Action (IPOA) for sharks in Progress on its implementation has been disappointing. However, the IUCN Shark Specialist Group plans to publish a report highlighting the plight of 100 species, propose recommendations for them, and reinvigorate international attention to sharks. Solutions for Survival As with most conservation issues, education is an effective means for changing human behavior and attitude toward sharks. "We now know enough about sharks to do a good job managing them," explains Simpfendorfer."We shouldn't make the same mistakes today that we made 30 years ago." To prevent repeating history, several experts advocate a grass roots approach to education, to instill an awe and respect for these creatures. "The more people know about sharks, the better they understand them. That understanding makes people more likely to want to help protect them," says Skomal. 3 of 5 12/31/69 7:23 PM

4 If sharks' futures seem bleak, we have ourselves to blame. But there is still time to reverse the damage for most species. Human behavior has placed sharks in danger, and we are the only ones who can save these imperiled fish. Media Frenzy, Not Feeding Frenzy The summer of 2001 saw enough high-profile shark attacks to earn it the nickname "Summer of the Shark." In truth, the actual rate of shark attacks did not increase--but the media coverage did. The fact remains that shark bites are exceptionally rare events. Bees, wasps, snakes, and even trips to the beach kill more people each year. According to the International Shark Attack File, in 2001 there were 55 reported shark bites and three deaths in U.S. waters, and 76 reported attacks and five deaths worldwide. George Burgess, Director of the International Shark Attack File, has studied sharks for nearly three decades. He has found that, in proportion to the millions of people who use the ocean, the frequency of shark attacks is exceptionally low. In fact, shark encounters are generally proportional to the number of people in the ocean. The most serious shark bites in 2001 took place over the Fourth of July and Labor Day weekends--times when high numbers of Americans are at the beach. "The number of humans in the water is the main motivator in shark attacks," says Burgess. "As the population of beachgoers in the water grows, the number of shark attacks increases proportionately." With human population growth and aquatic recreation increasing each year, logic and the odds dictate that the number of attacks will, too. Other scientists agree, adding that, as with any natural encounter, humans run a fundamental risk of putting themselves in danger when they venture into another species' domain. So what explains the media frenzy and the public panic during the summer of 2001? According to Burgess, an exceptionally dry season for major news, coupled with an attack on a child, sparked the media's interest. And, of course, he adds, "Sharks always sell." The Forgotten Species Spiny dogfish are often called the world's most abundant shark. While they appear plentiful, they are now one of the most besieged sharks in the Atlantic. The 1990s saw a decade of intense, uncontrolled fishing on mature female dogfish. Female dogfish do not reach sexual maturity until 12 to 20 years and carry their young for two years. Dogfish are also often considered low-priority fish by decision makers. Together, these factors are a recipe for fishery management disaster. In April 2000, NMFS enacted a dogfish rebuilding plan for federal waters (extending miles from shore) to limit catches and prevent a population collapse. Unfortunately, compatible measures in coastal state waters--essential to the plan's success-- were not adopted and directed fishing, discouraged in federal waters, continued closer to shore. Many states fell in line, but Massachusetts' catch limits were grossly excessive and seriously undermined the federal plan. In fact, the state's quota was nearly twice that for the entire Atlantic coast, and exceeded the federal possession limit by thousands of pounds. Now, the mature female population is severely depleted and the number of dogfish pups is at a record low for the sixth year. Recovery will likely take decades, even if fishing stops. This continued overfishing led the Atlantic States Marine Fisheries Commission (ASMFC) to enact a series of emergency measures to close state waters to dogfishing when the federal bycatch quota is reached. Environmentalists encouraged the action until a more permanent, federally compatible AFMFC plan is in place. Massachusetts, however, is gaining ground in its campaign to increase quotas and continue an unsustainable fishery. The Finning Controversy 4 of 5 12/31/69 7:23 PM

5 While banned in U.S. federal waters, shark finning still occurs in ocean waters worldwide. Fetching up to $200 a pound, the fins are used to make shark fin soup, an Asian delicacy. Depending on the species, a shark's fins represent just one to five percent of its body weight; 95 to 99 percent of the shark's remaining carcass is tossed back into the ocean. Smalltooth Sawfish While sharks are at great risk, their close relatives, the skates and rays, also face danger. The smalltooth sawfish, a unique elasmobranch with a long, toothed snout, was once a plentiful coastal species ranging throughout the U.S. South Atlantic. But with intensive fishing, habitat degradation, and bycatch (their tooth-studded snouts easily snag on fishing gear) their numbers have plummeted to dangerously low levels. Some scientists estimate that the U.S. population has declined as much as 99 percent, and this species is now thought to inhabit only a few areas of the Florida Keys and Everglades. As a result, NMFS has proposed to list and protect the U.S. population of smalltooth sawfish as endangered under the ESA. This proposal was a first for marine fish in U.S. waters, brought about by a 1999 petition from The Ocean Conservancy. A final decision is expected this summer. Unfortunately, according to Simpfendorfer, even with these efforts, sawfish recovery will take decades--or even centuries. Ocean Conservancy Update Led by Sonja Fordham, shark specialist and Fish Conservation Project Manager, The Ocean Conservancy has worked diligently to protect sharks and their relatives for the last decade and has enjoyed several major successes. It played a major role in development and implementation of the first management plans for Atlantic sharks and dogfish, as well as the U.S. Shark Finning Prohibition Act and the United Nations Shark IPOA. The Ocean Conservancy also filed the petition that led to NMFS proposals to list smalltooth sawfish under the ESA. It will continue to work on sharks' behalf in the future. Sharks desperately need your help, too. Speak up for sharks and write to your Congressional representatives to encourage better shark research and management plans. Log on to The Ocean Conservancy's website at to find out more about its shark programs, or join its Ocean Action Network to help make a difference. Educators' Resources Privacy Accessibility License Contact Copyright 2008 ProQuest LLC. All rights reserved. 5 of 5 12/31/69 7:23 PM