Rampant shark sightings and closures of popular Massachusetts beaches are leading a growing number of Cape Cod residents to build backyard pools, according to reports.

With at least 42 shark sightings tallied on Cape Cod even since just Aug. 1, local pool-construction businesses have reported sales skyrocketing as much as 40 percent, the Boston Globe said.

“They have told us that it’s because they’re afraid of the shark[s],” said Penelope Rich, who owns the Cape Cod Pool Company in Orleans with her husband, David, of customers. “They want to go to the beach and feel the sand on their feet and feel the water but then want to go home to their pools.”

David Cavatorta, who owns Seaside Pool Service in Yarmouth, said he can hardly keep up with increased sales, up as much as 30 percent.

“It’s been kind of crazy, to be truthful,” Cavatorta told the Globe. “I think more people are ready to say, ‘You know what? I want to hang out at the house, I want to put some money into it.’ ”

The boom in pool construction is due in part to increased awareness of sharks, thanks to media attention and apps that track the beasts, Cavatorta said.

Another business owner in Orleans, Craig Panaccione, said a woman called his Crossroads Landscape and Pools on Monday to say she was at the breaking point over the beach closures and shark sightings, particularly after she got a recent alert on an app called Sharktivity.

Panaccione of Cape Cod said he understood the woman’s apprehension to get into the ocean, as he no longer swims far offshore due to concerns about having a frightening shark encounter — like the Massachusetts family whose boat was brushed by a great white shark on Cape Cod Bay last week.

The area’s booming backyard-pool business is also a boon to those who service pools, one owner told the Globe.

“Sharks are good for business,” said Matt Wester of the Aqua Pool Company.

The spike in pool construction comes less than a year after the state’s first fatal shark attack since 1936. Arthur Medici, a 26-year-old man from Wellfleet, died when he was attacked while boogie boarding in September.

Just one month earlier, a doctor from New York was seriously hurt while swimming off Truro, according to the Globe.

Some pool contractors have said this summer has been so busy that they simply can’t keep up with demand.

“I’m turning people down because we are too busy,” Jim Treese, co-owner of Cape Cod Aquatics, Pools and Hot Tubs, to the Boston Herald in July. “I think it’s a unique situation. Who would have ever thought that something like sharks would expand a business?”