BRIGANTINE, N.J. - Eight seals were reported beached Friday in Shore communities, where an increased number have been seen in recent days as temperatures have steadily risen, officials said.

Seals were sighted on beaches at Avalon, Ventnor, Long Beach Island, Bayville, and Avon by the Sea, said the Marine Mammal Stranding Center in Brigantine, New Jersey's only facility dedicated to the rescue of sick and injured marine mammals and sea turtles.

The sightings are common at this time of year, when the weather turns more moderate, the center's officials said.

"It is important to remember that these wild animals can be dangerous and should be treated as such," the Marine Mammal Stranding Center said. "A frightened seal is unpredictable, and will lash out when necessary."

The seals had been kept away from New Jersey's beaches by freezing temperatures, but have returned and are "hauling out" to soak in the sun and enjoy the milder weather.

Many are traveling more and seeking food, and will come to the beach after eating to rest or dry off in the sun.

"Last week, we started getting more calls about seals as the ice melted in the back bays," said center director Bob Schoelkopf, who started the facility 40 years ago. "We have been getting sightings every day.

Friday, "we had the heaviest number of sightings," he said. "The busiest time we ever had was one day in 2011, when we had 15."

Schoelkopf said that the seals are "just trying to warm up," but that this can pose a danger to people and their pets.

"People are going out because it's warming up, and walking on the beaches and taking their dogs," he said. "Once the dog sees the seals, they take off, and when seal bites the dog, the infection is immediate.

"The owners will pay a lot of money to a vet to take care of the infection. That's one of the reasons you don't leave your dog go free."

People who have tried to move the seals into the water and dogs that have gone after them have been bitten in the past. No attacks have been reported this year, Schoelkopf said.

Most of the animals reported Friday were healthy, officials at the center said.

Two were picked up for evaluation at the center and were still being checked Friday night.

Shore visitors who come upon a seal or other marine mammal should stay at least 50 feet away and keep pets away, officials said.

They should also contact the center at 609-266-0538 and take a cellphone picture to help the center's staff with documentation.