The operation didn't eliminate all risk to the North Atlantic right whale -- line remains stuck in the animal's mouth. But the animal, which can eat, seemed safe from serious harm.

"We felt we did the best we could with this animal. We have no clue when we'll have our next opportunity. It is the middle of winter," said Greg Krutzikowsky of the Provincetown Center for Coastal Studies, a key player in a multistate consortium racing to try to save right whales.

North Atlantic right whales are among the most endangered large whales on Earth, with fewer than 400 surviving after being hunted nearly to extinction. State, federal and independent wildlife organizations monitor them year-round at various locations by air and sea.

Now protected internationally, the whales still face threats from humans, primarily collisions with ships and injuries from fishing gear that snags them while feeding under water. The gear, often made of long ropes, can limit the mammals' movement or gouge their skin to cause serious wounds.

"For most species, you don't manage the population on an individual basis. You're worried about population-level impacts. In this case, you can't lose a single animal. Hence this effort," said Mark Dodd, a Georgia Department of Natural Resources biologist involved in whale rescue missions.

When conservation groups find a whale in trouble, they marshal an immediate rescue, adapting old whale-hunting methods and tools to save the creatures.

The young whale at the center of Wednesday's action was first seen in September. Staff with the New England Aquarium -- part of an Atlantic Ocean whale disentangling network -- spotted the 35-foot-long animal in Canada's Bay of Fundy, where many right whales spend summers. Fishing line was caught in its mouth, knotted behind its blow hole and stretching about 40 feet behind it.

It wasn't clear whether the previously undetected animal was male or female. But it looked to be about 2 or 3 years old. And it quickly disappeared. Marine biologists didn't see any sign of it again until Jan. 15 off the coast of Georgia near calving grounds where the whales winter.

A nonprofit crew working for the Georgia Department of Natural Resources spotted the whale from the air. Using a satellite phone, the crew notified the state environmental agency, which dispatched two marine biologists in boats from Brunswick, Ga. They reached the animal in about two hours as the plane circled to keep its location clear.

At first, Dodd said, the mission looked simple. The whale was floating on the surface, asleep. Dodd and his partner, trained by the Provincetown Center for Coastal Studies program, were able to quickly approach and, with ropes and a buoy, attach a global positioning system that allowed the disentanglement network to track the animal.

When the whale woke, it dove to escape, sometimes staying submerged long enough to travel more than a mile. Dodd and his partner returned the next day, hoping to use cutters with long handles to snip the fishing lines. But the whale took off.

This time, however, it was dragging satellite tracking equipment, enabling the scientists and rescuers to know where it was heading.

Using the satellite transmissions, a whale specialist with the Provincetown center predicted that the animal would arrive in Onslow Bay off the North Carolina coast this week -- 400 miles north of where it had been spotted earlier this month.

And that's where it emerged. The weather on Wednesday was amenable for another approach.

So the disentanglement network, subsidized by the National Oceanographic and Atmospheric Administration, assembled crews from Duke University, UNC-Wilmington, the coastal studies program and elsewhere to make another rescue attempt. After taking off in two government boats from a NOAA dock in Beaufort Wednesday morning, they found the whale at 11 a.m. four miles off shore from Camp Lejeune.

Crossbow biopsy

Over hours, the crew was able to attach an anchor and two buoys to the rope, slowing the animal as whale hunters once did. The whale tried to evade them. In time, in an inflatable boat, they got close enough to cut some ropes with a hook knife on a long pole, again modeled after whalers' tools. Repeated tries to cut the line near the mouth failed.

The crew took many pictures of the animal and, using a crossbow and a bolt, took a biopsy the width of a pea from its hide. Studies of tissue from its skin and blubber will reveal its sex, its parents and, maybe, whether it's battling any illnesses.

To reach shore by dusk, the crews removed their equipment from the animal -- the tracking device, anchor and buoys -- and let it be. They were hopeful it would shake free from the line still stuck in its mouth.

They'll wait to see where it shows itself again.

"We don't know where it is," Krutzikowsky said at day's end.