There are only about 400 North Atlantic right whales remaining in the world today. After being hunted nearly to extinction in the 18th century, they are now most at risk from ship strikes. But starting today, the whales will get the right of way. A new federal rule requires ships 65 feet or larger to slow down to 11.5 miles per hour, or 10 knots, near East Coast ports when whales could be nearby. The whales -- so-called because they were the "right" whale to kill for oil because they floated when dead -- feed close to the surface and are especially vulnerable because many shipping lanes cut across their migration routes. Many of the creatures also get tangled in fishing gear, but scientists say ships are their main killer: At least one-third of all the right whales that died in the last decade died from ship strikes. The controversial measure has environmentalists cheering, but will the measure be enough to save the species?