BRIGANTINE — A harp seal rescued from a backyard duck pond has died, according to the Marine Mammal Stranding Center, which was caring for him.

The seal was rescued on March 23 from the home in Shrewsbury, underweight and exhausted, as the seal ate nothing but leaves and mud while it was trapped. It's usual diet is several pounds of fresh fish and ice.

After being rescued using a special net, he was taken to the rehabilitation pool at the center in Brigatine.

"Despite the extraordinary efforts by our animal care staff and veterinarian to nurse him back to health, he never fully regained his vigor. As much as he tried, he lost his fight," the center said on its Facebook page.

The family in whose yard the seal became trapped thank the center for their efforts.

"We are so grateful for you and your volunteers and it means so much all that you did. You are inspiring and just so good and we are sorry for the sadness you all must feel," Cecilia Kodama wrote in a comment.

The center's executive director, Bob Schoelkopf, told the Asbury Park Press the seal likely swam about two miles of a tributary before it became trapped.

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A necrposy will determine a cause of death.

The center said the death of an animal that is rescued is "always the hardest part part of animal rescue."

Harp seals spend most of their time swimming in the northern Atlantic and Arctic Oceans, according to National Geographic. They have powerful flippers, sharp teeth and can stay under the water for up to 15 minutes.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ

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