For two weeks, scientists have been tracking the Northern Right Whale and planning the unprecedented rescue mission.

A heavy fishing line is wrapped around the 20-year-old male's jaw and deeply imbedded in its head. It has caused an infection in the whale that continues to spread. Scientists say the infection will kill the whale unless the line is removed.

"It looks terrible," said David Mattila of the Center for Coastal Studies. "It makes you sick in the stomach and the heart to see an animal in that kind of shape."

For the rescue, Mattila and other scientists, who have saved more than fifty whales, created special hand tools to cut the line. But they have never seen something so deeply embedded or tried to remove a line at sea from the notoriously powerful Right whale which can be dangerous when angry.

Since the line is around the head, rescuers would approach the whale in a small inflatable boat at its most perilous spot, easy targets for the tail.

"We're dealing with a huge animal," said Charles Mayo, center for Coastal Studies. "Fifty, say 50 tons, 50 feet in length. It probably doesn't know we're trying to help it."

So, rescuers plan to do something never tried before. They plan to sedate the giant mammal with a tranquilizer.

Veterinarians and others involved in the rescue rushed to New Jersey to examine a young Northern Right Whale found dead off Long Island hoping there would be clues to the sedation in an autopsy.

One question rescuers have is 'how much do you give a 50-ton whale in a dart fired by a crossbow?'

Another question, rescuers have is 'what is the best area to inject the whale?'

The scientists are determined to try anything - even putting themselves in harm's way because there are only 300 Northern Right whales left and every death leads it closer to extinction.

"We're working right on the edge," said Mayo. "But considering the status of the animal and the condition of Right whales, it seems reasonable."

(Agencies)