Researchers studying ocean sounds came up with a whopper last year: the eerie bellow of blue whales cruising past New Jersey.

The Cornell Lab of Ornithology in New York has been studying whale sounds for three years, partly because it is easier to hear the whales than to see them in the vast Atlantic Ocean. The oceanic eavesdropping is giving scientists a greater appreciation for the secret lives of marine animals.

Last year, the lab's sound buoys off New York Harbor and Cape Cod Bay recorded six species of whale, including blue whales - the largest animals that have ever roamed planet Earth. The recording had to be sped up to be audible because the leviathans make noises at frequencies too low to be picked up by the human ear.

"It's only been a few years since we've been listening off the coast of New Jersey," said Christopher W. Clark, director of the Bioacoustics Research Program for Cornell.

Blue whales communicate with each other over hundreds of miles of open water. The lab's network of 19 underwater hydrophones off Cape Cod could pick up whale sounds as far away as North Carolina.

"I would assume we'd hear distant blue whales - singers off Bermuda," he said. "Lo and behold, that whale was moving right through our network, swimming right off Long Island past New York Harbor down past New Jersey along the continental shelf."

Blue whales hold the world record not only for size, at 330,000 pounds, but also for volume. They are the world's loudest animals, producing low rumbles of more than 165 decibels, the National Marine Fisheries Service says. A jet engine, by comparison, is just 140 decibels.

Boat strikes pose a serious risk to most whales. The lab uses its network of buoys to pinpoint whales and alert commercial boats about their presence near shipping lanes outside Boston, Clark said. Computers in the buoys send alerts to his iPhone when they identify nearby whales, he said.

"If we can do it off Boston, why aren't we doing it off New York and other major shipping ports in the country?" he said.

His lab posts live 24-hour reports of endangered right whales detected on its individual buoys. But the buoys also recorded humpback, minke, sei and fin whales.

The study is revealing just how noisy the ocean is.

"You have alternative-energy development with oil and gas drilling, container ships transporting goods, lots of fishing boats," said Leila Hatch, a federal marine biologist. "It's a busy place, and it's just getting busier."

Hatch studies whale sounds for the National Oceanic and Atmospheric Administration at the Stellwagen Bank National Marine Sanctuary in Scituate, Mass.

The scientists suspect manmade sounds may be interfering with whale communication, especially for northern right whales that migrate each year past New Jersey. Just 400 individuals are believed to remain, putting the species' population at the brink of extinction.

"Is there a biologically significant reduction in their ability to find food or navigate, or be in contact with one another?" she said. "The ultimate goal of the study is to add noise to a better understanding of impacts on marine life offshore."

Clark said the research holds promise about other ocean mysteries. The ocean is awash in the sounds of marine life, from the siren song of humpback whales to the rhythmic drumming of haddock. But many of these sounds just offshore are new to science.

"That to me is amazing," he said. "Here we are. We're recording 10 miles from where the pilgrims landed. And we don't know what's in the water."

Jeff Stewart, captain of the Cape May Whale Watcher in Lower Township, spends most of his days looking for whales.

"A friend asked me, ‘You must get bored of this,'" Stewart said. "I never get bored. I see something new every time I go on the water. Today, the dolphins were feeding on bunker."

He relies on friends in the fishing industry, spotter planes for bunker boats and U.S. Coast Guard reports to try to find whales less than 20 miles from shore.

His excursion boat this week came upon a fin whale, the second-largest animal on Earth. In the clear water, he could make out the white chevron markings on the whale's back.

Stewart said he has never seen a blue whale but always wanted to go looking for them off the continental shelf.

"A blue whale would be as big as the boat," he said.

His boat has a hydrophone, so tourists can listen to the chirping and clicking of bottlenose dolphins, he said.

"Sound travels seven times farther through water than air. The noise happening in one spot can be heard pretty far away," he said.

From his experience trying to track whales over the open water, Stewart said he immediately recognizes the advantage of studying the elusive behemoths through their sounds.

"A father was telling his son it was so difficult to find that one whale spout on the ocean. You can't kid yourself. Whales spend 90 percent of their lives underwater," he said. "It's certainly valuable research."

Contact Michael Miller:

609-272-7247

Want to hear a whale?

The Cornell Lab of Ornithology posted some of the whale sounds its buoys have recorded, including one blue whale's eerie call. To hear it, visit: http://www.birds.cornell.edu/brp/listen-to-project-sounds/blue-whale