One of two rare Newfoundland ponies born in the United States this year arrived in Jaffrey, N.H., Monday, the Newfoundland Pony Conservancy Center said.

The pony, named Cabot’s Stormin’ Sam, was born at the center around 6:30 a.m. Monday, said Emily Aho, the founder and executive director of the center.

“Sam is curious. He’s sweet. He’s only 3 days old, but give him a couple days and he’s going to be full of it. Moms always worry about foals, but in a few days, he’s going to say, ‘Hey, I can go running here without mom,’ and she won’t like that,’’ Aho said.

The pony weighs about 45 pounds and is 22 inches tall, the conservancy center said. Sam and his mother Storm are in good health.

Newfoundland ponies are an endangered horse breed. There are up to 500 worldwide right now and about 40 in the United States, Aho said. The peak population of Newfoundlands was once 12,000. Newfoundlands are known to be calm, friendly, and intelligent.

Newfoundland ponies usually go into labor only when humans are not present. “We got up in the morning and there he was. [Storm] was standing behind the shed and I called her and she peeked her head around. I looked on the ground at the end of the shed and saw a squirrel tail, and then I was like, ‘Oh, it’s a foal’s tail!’ ’’ Aho said.

Sam, who was born late in his mother’s pregnancy, is still learning how to walk straight, Aho said. The pony likes to sleep a lot. “He was a little chilly yesterday because of the rain and wind. We put one of our dog’s blankets on him yesterday because he’s so small and he dried right up and rolled in the mud,’’ Aho said. The pony may be sent to another Newfoundland conservation home in the United States to help breed new horses, Aho said.

Sam will be introduced to the public Wednesday night at the Jaffrey Chamber of Commerce After Hours event.

The conservancy center is asking for donations to help Sam and his mother, Storm.

Alyssa Lukpat can be reached at alyssa.lukpat@globe.com. Follow her on Twitter @AlyssaLukpat.