When Steve Wildasin and his sister, Linda, took a trip to Key Box Road Beach near Dewey on Wednesday morning, the most they planned to find were sea shells.

But at about 11 a.m., something unexpected flopped ashore.

At first, the siblings were unsure what they were looking at. But when they got closer, they realized they had come across a seal. Steve Wildasin said they began taking photos on their smartphones with a telephoto device, as well as a video.

"It was just laying there sunbathing," Steve Wildasin said, adding that they stayed at least 100 feet away from the sea mammal while documenting the sighting. "We knew better than to get close."

They did the right thing, according to four marine experts who say it's best to be careful around the aquatic mammals.

"The best thing to do is really just leave them alone," said Allison Ferreira, a spokesperson for the National Oceanic and Atmospheric Administration's Mid-Atlantic office based in Massachusetts. "Nine times out of ten, it's just hanging out, chilling out."

Beach-goers are encouraged to keep themselves and their dogs at a reasonable distance — 150 feet — away from the animal.

"Seals bite," Ferreira said. "It can cause harm to the human and the pet."

The Lewes-based Marine Education, Research and Rehabilitation Institute could not be reached for comment Friday.

Seal sightings peak along the East Coast in the spring during pupping season, which is when mother seals give birth. But sightings can happen year-round. NOAA confirmed with Delmarva Now that the seal in the video is an adult — and a healthy-looking one at that.

After they took the not-so-camera-shy animal's close-up, Steve Wildasin said the seal disappeared back into the water. They were able to share their experience soon afterward posting their photos and video of their serendipitous "friend" on some local Facebook groups.

"You never know what's going to wash up," Steve Wildasin said. "You never know what the ocean is going to do."

While most seals are just resting when they wash ashore, some may be sick or injured and in need of rescue. To report a stranded animal, call the MERR Institute at 302-228-5029. To learn more, go to www.merrinstitute.org.

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