Despite recent shark sighting, risk is said to be low for humans
By Nick B. Reid
Hampton Union, August 23, 2013
[The following article is courtesy of the Hampton Union and Seacoast Online.]
According to New England Aquarium officials, the most
common large sharks seen along the New Hampshire and
Maine coasts are blue sharks, which are exclusively
fish and squid feeders.
HAMPTON — When a dorsal fin is spotted poking out of the ocean water, it's time to stop swimming.
According to the New England Aquarium, there hasn't been a fatal shark attack in New England since 1936, but it's important to take the threat seriously until the animal leaves the area or is positively identified to be a non-threatening species.
"Public safety staff should consider the sighting of a dorsal fin as the presence of a large, unknown, unpredictable wild animal in close proximity to people that requires the securing of the area to avoid an unwanted interaction and to protect both people and the animal," Tony LaCasse of the New England Aquarium warns.
It was that threat that shut down Wallis Sands Beach in Rye this week, when several people reported seeing fins circling. That sighting comes on the heels of at least two fishermen pulling up sharks in the area recently and one false alarm in which an ocean sunfish was thought to be a shark in Seabrook.
Lee Brennan, a Hampton Beach lifeguard since 1965, said there have only been two or three confirmed shark sightings on the beach since then.
"We've had some that go by in the distance, but I think the topography of the beach keeps them away," Brennan said. "The (water along the) beach is long and shallow, there's not a lot of food for them. That's what they're after (food), not people."
Even for a shark researcher, it's difficult to make a positive species identification based on the picture of a dorsal fin in the water, LaCasse said. That's why, once the water is clear of swimmers, spectators should note the speed the animal is swimming, whether it's floating, swimming in a straight line, swimming in circles or moving erratically, and whether it's staying at the surface continuously — in addition to a gauge of its approximate length by responders in a vessel and its response to the watercraft being nearby. Those factors can help experts determine what species is present, which is important because some sharks are harmless to humans.
In fact, no sharks are out looking for humans, LaCasse said.
"Even in the case of large sharks, humans are not on the menu," he said, "but we still must take all precautions to minimize any negative interaction."
Sharks often follow schooling fish, such as herring, mackerel, bluefish or stripers, LaCasse said. Small sea birds are also attracted to these schools, he said, so it's possible to use their presence as an indicator of where schools are.
"Also checking with harbormasters, bait shop owners and recreational fishermen can give an indication of the presence of schooling fish. More food or bait in the water increases the likelihood of other large predators nearby," LaCasse said.
At least a couple of sharks have been pulled up by fishermen recently. A North Hampton-based fishing boat hooked and let go an estimated 800-pound porbeagle shark two weeks ago in the waters a mile and a half off Hampton Beach, according to Forever Young Charters' Facebook page. More recently, some fishermen in the Merrimack River in Newburyport caught and kept a 609-pound thresher shark, according to Paul Hogg, Newburyport harbormaster.
Hogg said fishermen aiming for tuna sometimes get sharks instead, since the two will go for the same bait, including herring and mackerel.
"They do catch sharks pretty often, but not thresher sharks," Hogg said, noting that blue sharks are by far the most common. "Thresher sharks are more common down south, like Martha's Vineyard."
Hogg said the porbeagle is typically a colder-water shark and isn't very common in this area. But he's heard of more shark catches than usual this year.
"The water temperature is definitely warmer than in years past, but it's not extremely out of the ordinary," he said, speculating as to the increase. "There's more people fishing now, too." With more bait in the water, more sharks are bound to be caught, he said.
The blue shark
If you're positive you're looking at a shark, it's probably a blue shark, LaCasse said. Some estimate that in July and August north of Cape Cod, 90 percent of the large sharks in the water are blue sharks.
They're commonly 5 to 7 feet long. Their upper body is grey with a blue hue and their bottom half is pale to white. Their body is slender, their snout is pointed, and their side fins are long and thin.
Researchers consider blue sharks to be a "timid species," LaCasse said, but they have been implicated in a few attacks involving people globally.
The basking shark
Though this is the most common shark to be mistaken for the great white shark, LaCasse said, "ironically (it) is a giant, harmless, mostly plankton feeder."
Basking sharks are enormous, the second largest fish in the ocean, reaching up to 32 feet in length.
"Any shark length in this region greater than 20 feet rules out great whites or any other large shark species and rules in basking sharks," LaCasse said. "If the shark is longer than the average small recreational boat, then it is a basking shark."
Basking sharks swim slowly forward with their large mouths open to collect small animal life on its gill rakers. They can be identified by their distinctive gill slits, which are very long and extend almost to the top of their backs.
The great white shark
Great white shark sightings are "extremely rare along the New Hampshire and Maine coasts," according to LaCasse.
Great white sharks don't prefer this area because the water is cooler than they like and it doesn't have their food of choice: large seals.
The Mola mola, not a shark
Mola mola, or ocean sunfish, can sometimes be mistaken for sharks because they'll sometimes have one large fin sticking out of the water.
But it's actually an "absurdly shaped creature," as LaCasse says, "with a large, often floppy top fin" that is visible when they're sunning at the surface during mid- to late-summer.
"Close up, the animal's bizarre appearance is a dead giveaway. Mola mola look like a biological experiment gone awry," LaCasse said.
LaCasse said the few recent injuries to people caused by marine mammals in New Hampshire "do not involve animals we would normally think of."
Dozens of people were stung a couple of years ago when a lifeguard removing a dead lion's mane sea jelly from the beach accidentally released its stinging cells into the water, LaCasse said. And a few years ago, a well-meaning local resident was bitten by a harp seal yearling when she tried to pick it up and return it to the water.
The most dangerous risks in the ocean "are generated by our own behavior," LeCasse said, warning of the dangers of overestimating one's swimming ability, lack of supervision, ignoring warnings or unusual weather or sea conditions.