LEWES, Del.- The MERR Institute says more seals are stranding themselves on Sussex County beaches, but it's not clear why.

Executive Director Suzanne Thurman says MERR has responded to 43 stranding calls since January, a higher number than usual. Thurman says a majority of the calls were for yearling harp seals.

"There could be a variety of reasons," explains Thurman. "They are stressed when people are around but they also lick the snow and ice. They are ice seals and so they lick the snow and ice to get fluid. So we don't know if they are confused and they start licking the sand instead. That's certainly one theory that has a lot of potential."

Only one of the seals was found dead, but two are being treated at the National Aquarium. Thurman says a deceased dolphin was found in Dewey Beach on Sunday, but a cause of death has not been determined.

The MERR Institute says they'll continue to respond to stranding calls, and in the meantime, public assistance is key. By law, people must be at least 150 feet away from a stranded marine mammal, and Thurman says keeping track of off-leash animals on the beach is very much appreciated.

"We are very thankful to everyone for helping to keep a safe distance from the seal, and for cooperating with the volunteers when they explain this requirement," she says.

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