Oceans of noise

Rocky Gauron has a habit of asking people to speak up.

''I'm a little hard of hearing, being in boats all my life, with the engines and all," said Gauron, 55, who pilots whale-watching trips and runs a boat charter business out of Hampton Beach, N.H.

The veteran mariner never imagined that the same engines he blames for his hearing loss could be robbing marine creatures of theirs, too.

Yet North Shore researchers worry that noise from a growing array of sources -- from whale-watching tours like Gauron's to two proposed offshore liquefied natural gas stations -- may pose a threat to marine mammals in the region, especially the endangered North Atlantic right whales that feed in the waters off Cape Ann. Scientists believe there are only about 350 right whales left in the world. Some whales, including right whales, communicate by calling out to each other across ocean basins, which extend thousands of miles.

''Over time, if a whale is approached and left, again and again, it's receiving lots of exposure to close-proximity noise that may impact an animal's ability to hear. It's sort of like going to a loud rock concert again and again," said Mason Weinrich, executive director and chief scientist at the Whale Center of New England in Gloucester.

Weinrich said he is particularly concerned about the potential noise from much larger ships that would come to the area if regulators approve pending requests from two companies to build liquefied natural gas stations off the coast of Gloucester. There would be vessels unloading at the sites nearly round the clock, according to spokespersons for the companies.

''If the noise is intense enough, the whales may avoid the area altogether, and the area is an important feeding habitat," Weinrich said. ''And if they stay, they risk hearing damage."

The cacophony of man-made sounds at sea is prompting researchers worldwide to scrutinize the effects noise has on the creatures that live below the surface. They worry that the rising levels from ocean traffic in New England and around the world may be harming sensitive marine life -- whales, dolphins, and other species that use sound to navigate while migrating, mating, finding food, avoiding predators, and caring for their young.

''This is a form of pollution that is affecting a very large portion of marine life," said Michael Jasny, author of a recent report, Sounding the Depths II, from the national, nonprofit Natural Resources Defense Council.

The council's report warned about dredgers that clear the seabed for ship traffic, pipelines, and other structures; pile drivers used for construction; commercial and military sonar; and innumerable jet skis and power boats. The combined effect is creating a ''continuous fog that is shrinking the sensory range of marine animals," the report said. The scientists link mass whale strandings and deaths in several countries to the use of nearby military sonar and high-energy air guns for oil and gas exploration.

In the coming months, marine life in the waters north of Boston could be affected by a variety of noise-producing projects, including: the LNG unloading stations; a cruise ship terminal in Gloucester that, officials say, could bring as many as 40 ships to the city annually; a planned pier in Salem for a Boston-Salem ferry; and a pier in Winthrop that, officials hope, will one day include a commuter ferry service.

While much of the research centers on whales, the Natural Resources Defense Council report said there are increasing signs that noise is affecting ''the entire web of ocean life." It noted a Norwegian study that monitored a large area around an ocean oil and gas exploration site where powerful air gun pulses were used to map the sea floor. The study found that catch rates for cod and haddock plummeted across an area larger than Rhode Island.

But scientists still have many unanswered questions, Jasny said.

''In general, this stuff is very hard to study," he said. ''All of these impacts on marine mammals and fish, they are occurring at sea, and their bodies often are not recovered."

Ocean noise is a new subject for many local leaders.

Martin O'Brien, chairman of Winthrop's Board of Selectmen, said officials have mostly focused on the potential revenue a proposed ''multiuse pier" would bring to his community. Preliminary estimates indicate that Winthrop would earn $100,000 annually from a town-owned pier, not including revenue from a much-discussed ferry service, said Winthrop's town administrator, Virginia Wilder.

In Gloucester, which bills itself as the ''Whale Watching Capital of the World," a top business leader said he doubted that noise from a new cruise ship terminal, slated to open next fall, would harm one of the region's prime attractions.

''Certainly the whales around Gloucester have to be feeling pretty good about life. They must be good, because they keep coming back," said Michael Costello, director of the Cape Ann Chamber of Commerce. He said the city's four whale-watching companies carry about 100,000 people a year, generating several million dollars in business.

However, some local leaders and fishing groups have raised concerns about the two LNG docking stations proposed for the waters off Gloucester. They fear that the projects, near prime fishing grounds, could harm the industry.

Both energy companies are still preparing information for regulators about potential environmental impacts from their projects, including noise levels. Still, spokesmen for both companies, Excelerate Energy LLC and Neptune LNG LLC, say they will take extra precautions to reduce noise.

For instance, both say they plan to construct their pipelines along areas of the sea floor with softer sediment to avoid loud blasting or dredging. Neptune says it will require ships to shut down most of their engines while offloading.

And Excelerate says it plans to study the noise levels emanating from a 900-foot-long ship at its LNG facility in the Gulf of Mexico to submit to regulators so scientists will have more concrete data to study when reviewing potential impacts of the project off the North Shore. The projects still need to be approved by a variety of federal and state authorities.

''The company is making every effort to minimize any environmental impact of this project," said Excelerate spokesman Doug Pizzi.

At the same time, state lawmakers are considering legislation that would create an ocean management plan to govern development in Massachusetts waters. The plan will likely require that noise levels be analyzed for potential effects on marine life, said Priscilla Brooks, a senior economist at the Conservation Law Foundation who has worked closely on the proposed legislation.

Regulation can be a tricky business, because noise, and the many creatures in the sea that could be affected by the growing cacophony, regularly travels across man-made boundaries, according to the report by the Natural Resources Defense Council. And there are no national laws or international treaties that deal comprehensively with the issue, the report concluded.

One of the federal government's top scientists for ocean noise said regulators need a much clearer understanding of the subject before they can impose rules.

''The amount of information that we have on the effects of large vessel traffic on distribution and catch rates is barely more than nothing. It's very, very limited," said Brandon Southall, head of ocean acoustics for the National Oceanic and Atmospheric Administration's fisheries program.

As scientists continue to gather data, Southall said, the federal government has been working with the shipping industry to design quieter vessels. Currently the government has no laws regulating noise levels from ships, he said.

Quieter ships, specialists say, may be good for business. That's because technology designed to quiet ship propellers may also improve a vessel's fuel efficiency.

Kathy Metcalf, director of maritime affairs at the Chamber of Shipping of America, a trade group of US-based shipping companies, said her organization is studying the costs of crafting quieter ships and whether such vessels would be more fuel efficient and potentially less harmful to marine life.

''It would be a win-win situation," she said.

Sound facts

Sources of noise at sea:

Sonar, shipping, dredging, power boats, jet skis.

Creatures potentially affected below the surface:

Whales, dolphins, other marine mammals; fish such as cod and haddock.

Distance whale calls travel:

Depending on depth, calls can travel thousands of miles across ocean basins.

Kay Lazar can be reached at klazar@globe.com.