A new way of scaring away sharks from fishing operations?
Electromagnetic field receptors and motion-detecting canals in the head of a shark
Seabirds attracted by longline fishing
Edited from a New England Council report:
“Students at the University of New England (UNE) are researching how electrical pulses can effectively protect sharks while saving fishermen time and money. (UNE has campuses in Portland and Biddeford, Maine.)
“The technology, which works by emitting small, erratic electrical impulses within the water, intends to scare away sharks, which can detect electrical fields, while leaving the intended catch unaffected. If the devices, which can be attached next to each fishing hook, are as effective as anticipated, they can significantly reduce shark bycatch on longline fishing equipment. This result would reduce waste and catch inefficiencies for fishermen and protect sharks from being caught unintentionally.
“Over the past decades, as fishing efforts have increased significantly, sharks and other marine life have seen their populations drop, in major part due to bycatch. The work by UNE students and faculty attempts to simultaneously minimize harm to wildlife, while boosting the sustainability and success of fishermen. While there is plenty of work left to be done before a final device is perfected, students understand how valuable this technology could become.
“‘[The fishermen] lose a lot of money, and they know it,’ Michael Nguyen, a second-year graduate student, told The Portland Press Herald. ‘We are still trying to work out specifics. This is a long way away from being integrated into any commercial fisheries, but there’s a lot of interest, a lot of need, especially now that they see the electrical field isn’t scaring away the tuna.’’’
Grace Kelly: Of seals, great white sharks and people
Great white shark
Via ecoRI News (ecori.org)
In the waning days of July, Julie Dimperio Holowach was swimming off the coast of Harspwell, Maine, with her daughter. What was a fun day in the surf and sun turned tragic when she was bitten by a great white shark and died as a result of her injuries.
The ensuing talk in the press and by New England beachgoers centered upon the rising seal population and its role in attracting sharks to local waters. Culling was discussed, and one headline read, “More Seals Means Learning To Live With Sharks In New England,’’ painting a picture that it’s the rotund sea mammal’s fault we’ve entered Jaws 2.0.
But the relationship among sharks, seals and humans is more nuanced and complex.
Of sharks, seals and humans, a John Steinbeck quote from Of Mice and Men seems appropriate: “Maybe ever’body in the whole damn world is scared of each other.”
Gray seal
Of seals
The return of gray seals to New England waters, after they were hunted to dangerously low numbers, is often blamed when a shark attack happens.
In Inuit folklore, seals were created from the fingers of Sedna, the goddess of sea animals. In one version of the legend, Sedna angers her father by rejecting her suitors and marrying a dog. Enraged, he casts her over the side of his kayak and cuts off her fingers as she tries to clamber back into it. Her fingers became the first seals, and Sedna becomes ruler of all creatures of the deep.
Other groups have their own legends about pinnipeds that slide through the water like fish but can also maneuver their way on land.
And in New England, two breeds of pinnipeds — gray seals and harbor seals — have a deep relationship with the region’s land and sea.
“There were a lot of gray seals and harbor seals all through historic times up through early 1900s,” said Kimberly Murray, a research biologist and seal research coordinator at National Oceanic and Atmospheric Administration’s Northeast Fisheries Science Center. “In fact, there was so many of them that there was a bounty for them in Maine and Massachusetts in the late 1800s, early 1900s. We don’t know exactly how many there were; I think … that it’s estimated something like 75,000 to 135,000 seals of both species were taken for the bounty, so there were a lot.”
While the presence of seals in this area has long roots, so does the history of humans hunting them, with seal meat even served at the first Thanksgiving.
“Seals and sea lions have historically been hunted,” said Monica DeAngelis, a marine-mammal biologist at the Naval Undersea Warfare Center, in Newport, R.I. “That was sort of the beginning of the relationship. Native Americans hunted them for subsistence and then European settlers, the early ones, used them for oil and meat, and for their pelt.”
Seal numbers declined steadily over the years, with people even picking them off for sport with guns in Narragansett Bay. The hunting and decimation of their numbers continued until the 1970s, when the Marine Mammal Protection Act was enacted, in 1972, and the Endangered Species Act was enacted, in 1973, both during the Nixon administration.
Harbor seal rests on the bank of the lower Connecticut River near Long Island Sound.
“They were really hunted down to low levels,” Murray said. “And there were a couple factors that allowed them to come back and recover. One of those was laws that were enacted in the state of Massachusetts in the ’60s and then the federal Marine Mammal Protection Act in 1972. These protective laws pretty much banned hunting.”
Today, gray and harbor seal populations continue to reclaim the territory they fled along the coast of New England, where they haul out to breed, molt, and have their pups.
The population of gray seals, specifically, comes from a larger colony up near Nova Scotia, and have been steadily repopulating a territory that they had to leave to survive.
“There’s estimated to be a quarter-million of gray seals in Canada, and they move around a lot,” Murray said. “We know that the animals that have come down to the U.S. starting in the late ’80s, early ’90s, are coming from that source population. They are able to return to a territory they used to occupy, and that’s why I think people get really surprised because they didn’t know they were here before.”
But not everyone is happy about the return of the seals. Besides competing with fishermen for various fish stocks, the newly healthy seal population has sparked the idea that with more seals comes more of their scariest predators: sharks.
Of sharks
Humans have long held a fascination with the wonders — and horrors — of the sea, and sharks are no exception.
“There are some cultures that revere the shark and worship the shark and there are others that are frightened of it,” said Gregory Skomal, a senior scientist for the Massachusetts Division of Marine Fisheries.
An illustration from the 16th-Century epic poem “History and True Novel of the Duke of Lyon de Bourges,” depicts a shark as a scaly, fanged monster with red eyes terrorizing the crusader Olivier de Bourges, who swings his axe at the beast as it devours his helmet.
Locally, more than a few historical records describe sharks as “monsters” and “man-eaters,” and a few vigilantes have even killed sharks as revenge for attacks. And the shark that lingers in man’s memory as the most fearsome of them all? The white shark, colloquially known as the great white.
“Here in New England and as far north as Newfoundland, white sharks are very well documented historically over the last several hundred years or so,” Skomal said.
But it was one summer, the summer of ’75, when the biggest and baddest of white sharks came to town. Its name was Jaws.
“Whenever you hear about a shark attack … you immediately think of Jaws,” said Marc Lapadula, a senior lecturer in film studies at Yale University. “People saw that film and they were terrified. People left their seats. I was there, I was 15 in 1975.”
Lapadula lectures on films that changed America, and noted that Jaws scared people so badly that during that summer many people avoided dipping so much as a toe in the briny blue.
.
“It was so scary to people that I had friends who had summer homes at Bethany Beach or Rehoboth Beach, Del., or Ocean City, Md., and that entire summer they would not go in the water,” he said.
Bradley Wetherbee, an assistant professor in the Department of Biological Sciences at the University of Rhode Island, has spent nearly 30 years of his life studying sharks. To him, the perceptions of white sharks, and even the spotlight on this one breed of shark, is overkill.
“There are a lot of people out there who only know one species — great white sharks — and they know one thing about them, which is that they bite people, they kill people,” he said. “If one person sees a white shark up there in the Cape, it’s in the news. People are fascinated with them.”
But there’s much more to sharks than their unfounded reputation as cold-blooded, doll-eyed killers. Indeed, with more than 500 different species of shark known to man, the white shark is just one of many fascinating creatures.
Wetherbee is quick to defend the cartilaginous fish in all its varied forms. One of his focuses is on mako sharks, which don’t have nearly the cult following that white sharks possess.
“Everything about makos is fast,” he said. “Their tail, muscles, everything. They’d swim circles around white sharks.”
But it’s great whites that are almost always at the forefront of the human mind when a shark attack occurs. According to the Florida Museum’s International Shark Attack File, white sharks are part of the “Big Three” when it comes to attacks.
“The white, tiger and bull sharks are the ‘Big Three’ in the shark attack world because they are large species that are capable of inflicting serious injuries to a victim, are commonly found in areas where humans enter the water, and have teeth designed to shear rather than hold,” according to the project’s Web site.
“When a white shark attacks, it attacks to kill,” Skomal said. “Their strategy during a predation event is to ambush. A seal at the surface is a very formidable predator itself, and in order for a shark to kill a seal, it has to ambush it with speed, stealth and strength. Power. So, if the shark is making a mistake and it thinks that person is a seal, it’s still going to strike with force, and it does so in a way that creates an amazing amount of traumatic injury.”
But Skomal noted that immediately after attacking a human, the shark usually realizes its mistake.
“Very rarely if ever do they consume the person because they realize, almost immediately, that they made a mistake, that this is not their normal food,” he said.
Of humans
While calls to cull growing seal populations have sprung up as a way to mitigate the few shark attacks that occur each year, for many experts, the dilemma of the interaction among seals, sharks and humans isn’t so cut and dry.
“White sharks are known predators of seals; that’s what they augment their diet with as they get larger, when they get to be over nine feet in length. They’re built to kill seals and that’s what they do,” Skomal said. “So it makes perfect sense that as the seal population rebounds and they are recolonizing areas, white sharks are going to take notice and begin targeting those animals, and because those animals tend to be piled up close to shore, the chances of [humans] encountering a white shark are a bit higher.”
Sunset on Race Point in the Cape Cod National Seashore. That more and more people seek to spend time on the seashore means more encounters with seals and sharks.
— Photo by SeduisantRedux
But part of what is happening, and part of the animal equation that is often left undiscussed, is the human element.
Visiting the seashore wasn’t always a relaxing leisure activity. Up until the 1880s, the seaside was a wild place where shipwrecks occurred, storms destroyed buildings, pirates lied in wait to attack, and where monsters lurked in the dark waters. It wasn’t until the 1860s that the beach became a place popularly known for its curative qualities. Coupled with the Industrial Revolution and the birth of easy and increasingly affordable transportation in the form of automobiles, a jaunt to the seaside became accessible to more people.
That trend continues today.
In 2018, nearly 4 million people visited the Cape Cod National Seashore. Compared to the 30,000 to 50,000 seals estimated to be on the Cape in 2017 and the 147 white sharks identified in 2016, humans are the species present in the largest numbers.
And while we fear sharks and blame seals, we’ve had our own terrible impacts on both species throughout history, from hunting seals to the brink of extinction to the more recent overfishing of sharks.
“It appears that the white shark population, which was quite healthy, was overexploited during the ’70s, ’80s and ’90s,” Skomal said. “During that time, there was a massive increase in shark landings driven by seafood markets and demand for shark fins. Then, in 1997, the U.S. government, followed by states, implemented regulations that protected white sharks: You could no longer target or land white sharks to keep. So … the population appears to be rebounding back to historical levels. But we don’t think it’s there just yet.”
While humans have attempted to correct the wrongs we’ve wrought throughout history when it comes to species decimation, the urge to control our environment still sits deep in the marrow of our bones. But like Captain Ahab hunting his white whale in Moby Dick, sometimes the desire for control ends with our own demise.
“When you have an ecosystem that’s well-balanced, that speaks wonders to the health of the ocean,” said DeAngelis, the marine-mammal biologist at the Naval Undersea Warfare Center. “And when you have a healthy ocean, you have healthy environment for the rest of us, for humans. I would be very concerned if all of a sudden all of the sharks disappeared, all of the seals disappeared, because that means something is going on with the ocean. It's a delicate balance, and humans have kind of tried to play God.”
Grace Kelly is a journalist with ecoRI News.
Sharks off the beach!
White shark cruising the surface.
Photo by Brocken Inaglory
Adapted from Robert Whitcomb's Digital Diary, in GoLocal 24.com
Every time there’s a very rare (and always much publicized) attack by a white shark on swimmers or surfers (or surfboards) off Cape Cod, there’s a new proposal to kill as many of these creatures as possible off the Cape’s beaches. Consider the proposal that surfaced last week to use drum line traps to kill the sharks. That’s a terrible idea. Sharks are part of the eco-system and wiping them out in certain waters will hurt other species, too. Everything in the sea is connected.
The best advice to swimmers and surfers in waters known to be occasionally visited by sharks is not to go out beyond the surf line. White sharks, the scariest ones, like deep water and usually attack prey from below. It’s good to remember how rare shark attacks on people are in New England, with no more than half a dozen in Massachusetts since 2000. (There’s some confusion about the exact number of documented attacks.) The last fatal attack in the state was off Mattapoisett, on Buzzards Bay, in 1936.
The seal population has swollen along the southeastern New England coast in recent years, attracting sharks. If you see seals, you might want to keep closer to the shore. At the same time, people are using the beaches more than ever. But that’s no excuse for humans to destroy yet another piece of the marine eco-system.
Meanwhile, with global warming, we may see more white sharks on the New England coast.