Scientists: We Need To Learn More About Sharks And Seals

By: Ed Maroney

Topics: Sharks , seals

Sharks and seals have been part of the local ecosystem for years, experts say. MASS DMF PHOTO

ORLEANS With no simple answers for how seals and sharks are affecting swimming off Outer Cape beaches, the best approach may be coming up with more complex questions.

Shark and seal experts joined Cape Cod National Seashore leadership at Nauset Regional Middle School Nov. 14 for a public forum that laid out possibilities for better understanding the animals' behavior and using that knowledge to inform decisions about public safety.

“Sharks have always been here and always will be,” Seashore Supt. Brian Carlstrom said in opening the meeting. “Their numbers are changing. When you choose to recreate in the ocean, you're assuming a level of risk. We want to make it as safe as possible, but we can't eliminate (the risk).”

“I don't know if I have a solution,” Dr. Greg Skomal of the state Division of Marine Fisheries told the audience of about 200. “There's no silver bullet there. We're trying to learn more about the behavior of animals in these shallow waters to determine what patterns exist.”

Skomal and his research associates aren't ready to present results of their shark population study (“If I tell you a year from now there are 500 sharks out there, that's one thing,” he said. “If it's 5,000, that's something else.”), but patterns have emerged.

“The Outer Cape and inner Cape down to Wellfleet jump out at you as the place most sharks are spending time,” said Skomal. “There's a distinct seasonality. June is incredibly slow. July is different year to year; this year (saw) a large number early in July. The peak months are August, September, and October.”

For many of the animals, “Cape Cod is not their final destination,” Skomal said. “Some set up residency, some treat Cape Cod like a Burger King going up (Route) 95 to Canada.”

He hopes that the sharks that have been tagged will reveal behavioral patterns that “will help us perhaps define optimal times when not to go to certain parts of the Cape at certain times of year.”

Skomal raised a subject “we're always harping on. We need to know more about (sharks') prey. We need to know more about the behavior of seals... The next five years of our research will be centered on (sharks') local distribution and behavior relative to seals.”

That set up a segue to Dr. Andrea Bogomolni of Woods Hole Oceanographic Institution and the Northeast Atlantic Seal Research Consortium. She said there are about 70,000 harbor seals and half a million gray seals in the North Atlantic, with 23,000 gray seals found around Cape Cod and southeast Massachusetts.

Telling Skomal she was “very jealous of all the sharks you've tagged,” Bogomolni noted the first-ever tagging of nine wild adult gray seals in 2013. The Consortium found that Northeast Atlantic seals “are really using the entire ecosystem. There are animals that stay close and ones that go to Sable Island (off Nova Scotia) and use the continental shelf.”

Seals are “a sentinel species for what happens in the ecosystem,” said Bogomolni, who labeled the notion that seals cause beach closures “misinformation.” She said a Consortium study found that “where the seals are, there are fewer beach closures. So far as we know, seals are not responsible for beach closures.”

Seals and great white sharks in the same place “is not a new topic,” Bogomolni said. “I've been talking to Greg about sharks and seals for 18 years. They're normal to have in the ecosystem.”

Lisa Sette of Provincetown's Center for Coastal Studies has been monitoring seal haulouts on the Cape and Islands for more than a decade. She praised the cooperation of the Seashore and volunteers in educating thousands of visitors about the animals.

Sette said researchers want to refine estimates of seal numbers, monitor them for wounds and other signs of interactions with sharks, and examine scat samples to determine what they're eating off Cape Cod.

The animals studied by Leslie Reynolds, the Seashore's chief ranger, are bipeds with a taste for fried food and lobster rolls. Her job involves protecting the public that enjoys the beaches, and the lifeguards that protect them. In 2012, the year she arrived on Cape Cod, two shark-related events, including a biting incident, focused her concerns.

“The Seashore from that point on was committed to educating ourselves and the public about white sharks' presence, behavior, and how we were going to keep the public and lifeguards safe with these predators right off our beaches,” she said.

That led to creation of a regional shark working group, which includes the Seashore, Cape and South Shore towns, state agencies, and the Conservancy. “We meet quite often and we're constantly in communication with national and state parks and shark experts across the country and other countries,” Reynolds said.

Accomplishments include the Sharktivity phone app, shark education signs and cards distributed widely, warning flags for beaches, a Frequently Asked Questions fact sheet, and collaboration with the Conservancy.

Cape fire departments got a “big, big shout-out” from Reynolds for helping with “stop the bleed” training, and the Seashore is looking into affordable shark attack kits for the public that would include gloves, bandages, tourniquets, and a blanket.

With 27 temporary swimming closings this year due to shark sightings, the chief ranger said lifeguard training is a priority. “They're extremely professional and work very hard on fitness,” she said. “We will continue to equip them with safety equipment and train them in tourniquet application. We're working toward having a shark attack kit at every booth.” Later, responding to a question about extending the lifeguards' season into October and beyond, Reynolds said that the majority “have other professions” and family obligations waiting.

Carlstrom stressed that the closures related to shark sightings were for swimming, not for using the beach. After all, he said, he'd read that “70 percent of the people who go to the beach never even get in the water.”

Opening up the meeting for questions, Rich Delaney, chair of the not-yet-reauthorized Cape Cod National Seashore Advisory Commission, acknowledged that “this is an emotional issue for people.” This year alone, two swimmers were injured, one fatally, by sharks. He asked that people “focus on the issues and the progress made on better understanding where we are.”

Earlier, Skomal said there are “less than 100 attacks globally by sharks, and less than 10 percent are fatal. All it takes is one. It changes the way you think.”

A Harwich surfer asked about use of a “clever buoy system” operated by artificial intelligence that can differentiate a shark from a seal and send out a warning. Carlstrom called the technology “very intriguing” and said the Seashore is following tests in Newport, California.

“One of the most threatening things today to the ecosystem is the gray seal,” an Orleans man said. “(What is) the silver bullet we have to eliminate the problem we have with blood in the water? Let's eliminate the seals.... There are 23,000 seals on Cape Cod. If we eliminated every one of those seals, that's only 5 percent of the population. Ask the seal people how that would affect the stability of the gray seal population in the North Atlantic.”

“If you were to eliminate the seals here,” Bogomolni said, “you would have seals come from Sable Island in Canada, and they're 500,000. They'll still be here. They do play an important ecosystem role that we're trying to understand before we eliminate them again.”

“What that tells me,” the questioner said, “is that we need sustained harvesting like we did for centuries.”

A lifelong surfer from Truro highlighted the lack of cell phone service on the beaches as a barrier to reaching first responders. “We're working with OpenCape to evaluate what sort of systems could be located at the six Seashore beaches and 22 town beaches,” Carlstrom said. “We're simultaneously looking at emergency call towers. There likely never will be (100 percent coverage). It's too isolated with the cliffs getting a signal down to the beach. We are looking at where we can improve the signal and also at satellite technology.”

An audience member asked how sharks are spotted. “By the human eye, or by flying the plane overhead,” Reynolds said. “We're in the air twice a week.” The auditorium exploded in laughter and applause when the questioner asked, “Which days?”

“I think we would fly every day if we had the funds and the weather,” Reynolds said when things quieted down.

To read the Seashore's “Frequently Asked Questions about Sharks and Public Safety,” go to