August 16, 2012 (BOSTON) _ Researchers say increasing amounts of underwater noise, largely from shipping traffic, is covering right whales in "acoustic smog" that makes it harder for them to communicate.

The endangered North Atlantic Right Whale relies far more on sound than sight, using noises to maintain contact.   

Federal scientists and Cornell University researchers estimate that in the last 50 years, the area where the whales can effectively communicate has fallen by two-thirds.

They say that's cutting down on the whales' ability to gather and share vital information that helps them find food, avoid predators, reproduce and protect their young.

Researchers say the next step is figuring out how to address the problem.