The peak months for shark activity off Cape Cod are August and September. Here’s what we’ve seen so far.

A woman takes a picture of the shark advisory at Marconi Beach in Wellfleet on August 24 after a shark bit a standup paddle board. —Craig F. Walker / The Boston Globe

Summer vacation may be almost over for humans, but the season for sharks off Cape Cod will go on for weeks after the tourists have gone home.

The peak months for shark activity in Massachusetts waters are August and September, according to Greg Skomal, the senior fisheries scientist for the state Department of Fish and Game who leads the Massachusetts Shark Research program.

“There’s been a lot of activity over the last week,” he said. “And we expect that in August.”

Skomal and his team, working with the UMass School for Marine Science and Technology and the Atlantic White Shark Conservancy, are in the fourth year of a five-year study gathering data to calculate the local population of white sharks and learn more about the predators’ movements and behaviors.

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“The more we know about the movements, the patterns of these animals, the better we can equip beach managers with information so that they can enhance public safety,” he said.

In 2014, over the course of 25 survey trips for the study, Skomal and his team identified 80 individual sharks. In 2015, with an increase to 41 survey trips, they identified 141 sharks. Last year, in over 40 trips, they picked out 147 individual sharks, about 40 percent of which he said were sharks the team had observed in previous years.

The researcher said he’s shot hundreds of videos of white sharks this year, and, at the end of October when the season is over, he and his colleagues will start the labor intensive processes of going through all the images, using the animal’s color patterns as the primary means for identifying, and tabulating, the individual sharks observed.

“Last year, we had pretty strong July, August, and September,” he said. “And when I say strong, we saw a lot of white sharks in July of last year, which is more than what we saw this year. This year was really slow to ramp up, and it’s probably associated with the cooler spring that we had. June was very slow. July was very slow.”

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But August, he said, has been “extremely strong.”

Here’s a look at just some of the shark activity witnessed by whale watchers, fishermen, and beachgoers in the last month.

July 31: A shark tried to taste an underwater camera

The very end of July kicked off with a curious shark getting close to a GoPro being used by Skomal to study the creatures off the elbow of Cape Cod.

Aug. 10: A seal was chomped in half by a great white shark

Beaches in Chatham were closed after a shark was spotted in the town’s harbor. Researchers also observed half a seal floating nearby from a predation.

Aug. 11: Great white sharks were spotted feasting on a dead whale

Passengers aboard a whale watch witnessed the predators snacking on a dead minke whale north of Race Point Beach in Provincetown. The Atlantic White Shark Conservancy also visited the scene and posted photos of the event.

Aug. 12: A fisherman had his catch stolen by a shark

A great white shark leapt out of the water to snatch a fish off a fisherman’s line in Cape Cod Bay, startling the men aboard the charter boat on Billingsgate Shoal.

Aug. 21: A shark feasted on a seal off Nauset Beach

Vacationers watched as a shark attacked a seal off of Nauset Beach, turning the water red and sending surfers and swimmers rushing for shore.

Aug. 23: A shark tried a bite of a paddle board at a Wellfleet beach

Days later, a shark took a bite out of a paddle board off Marconi Beach. The man aboard the paddle board, who was knocked down by the force of the bite, described the experience as “being on a motorcycle and getting hit by a truck.”

Skomal said the two most recent incidents are consistent with what he and his colleagues have said people should be mindful of all along — that the sharks are here to prey on seals.

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“In both instances there were seals in the area,” he said. “Be mindful that if you decide to swim out a great distance or move off the beach, there’s the potential for interaction with one of these sharks if there are seals in the area.”

If you’re one of the beachgoers shaken by the last week’s shark occurrences, Skomal said it’s important to remember that sharks are eating seals every day — sometimes in visible spots like off Nauset Beach and other times in a remote area where it isn’t witnessed by humans. The rebounding seal population — a viable and preferred prey for great whites — has drawn sharks closer to the shore, he said.

“I think when people see it like they did last week, it’s a reminder that this is a predator-prey interaction,” he said. “This is what’s happening here.”

Skomal said there hasn’t been a fatal shark attack in Massachusetts since 1936.

“Keep that mind,” he said. “Don’t be cavalier, but realize the probability of an event is really low. But take a precautionary approach.”

At the top of the list of the Atlantic White Shark Conservancy’s safety tips is this — don’t swim near seals. The conservancy also advises swimming close to shore where your feet can touch the bottom, staying in groups when paddling or swimming, and avoiding wearing shiny jewelry. You can also see where sharks have been reported on the conservancy’s free app, Sharktivity.