When it comes to animal rescues, Island naturalist Gus Ben David is used to happy endings. He’s helped return 400-pound sea turtles to the ocean and helped return struggling, orphaned great horned owls to the skies. But nature isn’t a Disney movie, even when it is on camera. And that was never more clear than on Monday.

Mr. Ben David was driving home when he received a call from his longtime friend and premier osprey researcher Rob Bierregaard.

“Rob says, Gus, take a look at the osprey cam at the pumping station in Oak Bluffs,” Mr. Ben David said. “One of them has probably gotten monofilament (fishing line) tangled up on its leg because it is in the nest flailing with its wings trying to move forward, and it can’t.”

Osprey are notorious junk collectors and will use anything they can lay their talons on to construct massive nests atop poles, chimneys, and other high points. So Mr. Ben David rushed home and took a look at the camera himself.

“Sure enough, there it was,” Mr. Ben David said.

He then sped over to the pumping station and waited while an Eversource worker removed the struggling chick from its nest, 60 feet above Lagoon Pond. Although Eversource isn’t in the osprey removal business, the utility company has a vested interest in keeping the pumping station osprey healthy because the birds could decide to nest on their adjacent electrical poles. It’s a relationship that goes back 50 years.

“They’re involved, not out of the love of the osprey, which they do,” Mr. Ben David said. “But it’s in their interest to keep that pair viable and on that pumping station nest because right adjacent to it are a number of electrical lines, very complex, transformers and all, and last year we had an osprey electrocuted on them.”

When the lineman brought the bird down to Mr. Ben David, however, he immediately realized the situation wasn’t so simple.

“It had a prenatal deformity,” Mr. Ben David said, speaking about the bird. “It was about twice as small as the other chick, and one of its legs was totally atrophied and useless . . . That’s a euthanasia case.”

Mr. Ben David said because of its physical deformity, the chick would have never fledged, nor would it have entered the gene pool. But for him, the situation was less about the grim end result and more about the technology that made it possible.

“The double-edged sword is that, yes, these camcorders on these nests are educational. And people can watch the dynamics of these things that you normally would not be able to see,” Mr. Ben David said. “And as long as everything is going okay and there’s enough food to feed the young ones, everything goes fine. But that’s not nature’s way.”

Felix Neck wildlife Sanctuary used to have camcorders on its barn owls, with up to 50,000 people watching the birds every day. But back in the winter of 2014, heavy snows threatened the animals as they struggled to find food. None of them survived the winter, and viewers weren’t happy.

A similar situation played out with an osprey camera in Falmouth, where other osprey dive-bombed and caused many of the young to fall from the nest. Despite public pressure, wildlife experts refused to intervene.

“If one gets knocked out of the nest, or its siblings bully it, or it starves, that’s what happens,” Mr. Ben David said. “When I teach a class, there’s no anthropomorphism. I try to teach that you’ve got to accept nature’s way. It’s called gene pool selectivity. Only the superlative survive to carry on the gene pool.”

Mr. Ben David said he made the decision to work with Eversource to help this struggling bird when he believed that it was tangled in monofilament — an anthropogenic cause, rather than a natural one.

“The reason that we intervened is because, at that time, visually, we thought it was wrapping line, a manmade thing. So in those cases, it includes human dignity and we will try to intervene to rectify the situation,” Mr. Ben David said. “Unfortunately, that wasn’t the case.”

Despite the sad ending, the overall story of the osprey population on the Vineyard has been largely a happy one. Back when the Island was mainly agricultural, farmers would put up wagon wheels on the tops of poles in an attempt to lure osprey to their property. Farmers loved the notoriously territorial fish-eaters because they would scare off other birds of prey, like red-tailed hawks, that threatened free-range chickens. But by the mid-20th century, ospreys had all but disappeared from the Island.

“I put my first osprey pole up in 1970,” Mr. Ben David said. “There were two breeding pairs of ospreys left on the Vineyard. And that’s where it started.”

Mr. Ben David now estimates there are now close to 100 breeding osprey pairs on the Island. There’s only one, however, with a camcorder. And there’s only one chick left in its nest.

“Let’s hope that he successfully fledges,” Mr. Ben David said. “And if he just has a problem that is due to nature, we won’t do anything.”

Mr. Ben David believes that through further education, people will better understand nature’s sometimes harsh reality — and in so doing, better appreciate its beauty as well.

“You try to teach the magnificence of it,” Mr. Ben David said. “Nature does not survive by compassion. The only animal that survives and thrives by compassion, is, we hope, the human being.”