The long journey of a Kemp’s Ridley sea turtle named Shellbey came to a sad end early this month, when the turtle was found dead in an isolation tank at its temporary home at the University of New England’s Marine Animal Rehabilitation Center in Biddeford, Me.

Fortunately the family that found the turtle washed up on the Vineyard’s north shore shortly after Thanksgiving last year got one last chance to see Shellbey, when they visited the rehabilitation center in January.

At press time yesterday, the family was unaware of Shellbey’s death, despite best attempts to reach them.

Linsey Lee, her husband Brendan O’Neill and their daughter Mya were given an exclusive tour of the rehabilitation facility, which functions as both hospital and research center for unhealthy and endangered sea creatures.

And they also got a chance to see Shellbey, though not face to shell. A friendly staff member went into the isolation tank to point out Shellbey among the other animals as the family watched a live video feed from an observation area.

“We couldn’t go right down into the pen because they have a lot of different animals in there, and they’re worried about diseases passing to humans,” said Ms. Lee last week. “[But] it was wonderful because we got to see the program, and we got to see Shellbey.”

And especially for five-year-old Mya. “She knew what was going on, and she was excited about it,” said tour guide Ann Watson.

“It’s a wonderful operation up there,” said Ms. Lee. “It’s wonderful to follow [Shellbey’s] progress, and it’s great to see him or her floating around in the tank,” she said. Shellbey’s gender was unknown as it is difficult to determine the sex of a turtle without dissecting it.

Ms. Lee and her family quickly sprang into action when they found the wounded turtle on the beach early this winter. “He was turned over and he had a gash in his flipper and the back of his shell had gashes in it . . . [so] we brought it into the house overnight,” she said. When the turtle lived until morning, they teamed up with Gus Ben David and David Grunden, the Oak Bluffs shellfish constable who is in charge of dealing with marine animals stranded here, enacting a rescue chain that took Shellbey off the Island on the ferry to be turned over to the northeast sea turtle stranding coordinator Bob Prescott. After a short stop in Wellfleet for an initial assessment, Shellbey was moved to the New England Aquarium for treatment. The turtle seemed to do well at the Aquarium, and was eventually moved to the rehabilitation center.

“We try to move these animals through . . . as quickly as possible. Some stay longer than others, and others are here a couple of months and then leave,” said marine mammal rehabilitation coordinator Keith Matassa. “[Shellbey] was still on some medications, and was still under vet care, but she seemed to have been responding to everything.”

Shellbey is one of many sea turtles found stranded in the Cape Cod area this year. Mr. Matassa said the number was somewhere between 80 and 120 turtles, which he said is higher than usual. Most strand in Wellfleet Bay, probably because of the warmer water temperature and ample food supply in summer. The problems arise when the turtles fail to leave as water temperatures drop. Mr. Matassa said that it’s hard to know the exact reason why they stay. He added that it’s much less common for turtles to be found on the Vineyard.

There was one other sea turtle to wash up on Vineyard shores this year, said Ms. Lee, around when Shellbey was found, but was dead by the time of discovery.

Mya felt a special connection with the turtle she helped rescue with her parents. She was the one to pick out the turtle’s name, which Ms. Lee said she thought was especially fitting because it is gender-neutral and references the turtle’s shell. “I thought it was very appropriate,” said Ms. Lee.

Ms. Lee said in her interview with the Gazette that Mya had maintained her bond with the turtle, even though she had to give it up. “She’s always drawing pictures of Shellbey,” said Ms. Lee. “It’s very exciting for [her] to watch the progress and learn about sea rescue operations . . . We’re excited to keep watching Shellbey’s journey.”

Ms. Lee and Mr. O’Neill also took Mya to tour the New England Aquarium before heading up to the rehab center to visit Shellbey. The tours provided a great opportunity for Mya to learn more about her turtle friend.

“We started out by viewing the turtles from upstairs,” said Ms. Watson of the family’s visit. “We talked about the Kemp’s Ridley as a whole, the fact that they are the most endangered sea turtles.” They got to see Shellbey, and also saw some of the other turtles being rehabilitated at the facility. Mr. O’Neill snapped pictures while they inquired about Shellbey’s release into the ocean, expected to be sometime this summer.

Mr. Matassa said that Shellbey’s death was unexpected but not unusual. “One of the things about our field is, unfortunately, animals can hide things quite nicely,” he said. “They’re wild animals, so they hide what’s wrong with them very well. If you show weakness in the wild, you’re going to get picked off by the next predator. So they act normal, they do everything normal, even though they may be dying. So we never know.”

Mr. Matassa said they have done some tests since they found Shellbey dead, including a necropsy, and the results did point to some health issues. But the cause of death has not yet been determined.

Even though Shellbey didn’t live long enough to be released back into the wild, the turtle would surely have died months ago on a cold and lonely beach if it weren’t for Ms. Lee, Mr. O’Neill and Mya. And they continued to keep an eye on her progress, even if it meant traveling up to Maine to do it. Ms. Watson said it’s quite unusual for rescuers to come back to visit the animals, “especially coming from so far away.”