Federal agency charts strategy to understand and ease the impact of noise on marine life

With the release of a formal strategy on Tuesday, the National Oceanic and Atmospheric Administration is aiming to minimize the effects of ocean noise on marine life.

In the works for the past six years, the Ocean Noise Strategy Roadmap is expected to guide NOAA over the next decade as it works to better manage noise in the ocean, officials said.

The document calls on the agency to build the current body of science to better understand ocean noise and to create tools for assessment, planning and reduction of noise-making sources, along with educating the public about the problem.

“I’m very excited about this. It’s going to help us make the best decisions based on the best science,” said Jolie Harrison, chief of the permits and conservation division of the NOAA Fisheries Office of Protected Resources.

In a news conference Tuesday, Harrison and other NOAA officials pointed out that sound is critical to the survival of many aquatic species. It’s used in communication, navigation, feeding, avoiding predators and in choosing a mate.

Noise can be caused by natural or human sources, but there’s growing evidence that sounds generated by humans, including ship noise, are taking a toll on marine life by such things as masking sounds produced by prey and altering the behavior of prey.

What’s more, a study last month in New England found that ocean noise appeared to interfere with the foraging behavior of 10 different species of whales.

In Hawaii, the military’s use of sonar has long concerned marine mammal conservationists and has prompted protests. A year ago, the Navy in a settlement with environmental groups agreed to limit its use of sonar and other training activities that inadvertently harm whales, dolphins and other marine mammals off Hawaii and California.

The issue of ocean noise was also addressed during the World Conservation Congress held earlier this month in Honolulu.

Jason Gedamke, NOAA ocean acoustics program manager, said Tuesday that sound travels underwater incredibly well over vast distances, and marine life has evolved for millions of years using sound to survive.

“But human activities have been increasing, with ships, construction, industrialization. Humans have added to the noise level in a fraction of a time scale,” Gedamke said.

In 2010 two NOAA working groups were assigned to the issue — one that mapped the density of marine life in U.S. waters and another that mapped ocean sounds. A symposium that followed recommended a long-term plan to improve NOAA’s ability to manage impacts.

Volunteers within NOAA began working on the initiative in 2013, and the agency eventually received more than 85,000 responses during public comment on the draft road map.

On Tuesday, officials said they are already taking on some of the plan’s recommendations, including launching an underwater network of acoustic monitoring sensors throughout U.S. waters.

“There is surprisingly limited data on long-term ocean noise,” Gedamke said.

One study off the Central Coast of California indicated that the level of low-frequency noise — the kind most damaging to large marine mammals such as whales — has swelled over a half-century by 2 decibels to 3 decibels per decade, due primarily to an increase in shipping.

To help fill the data gap, NOAA is setting up an ocean-noise listening station network, with 12 listening stations to document and characterize long-term trends, Gedamke said.

Other NOAA projects underway include developing a long-term passive acoustic data archive, supporting the adoption of voluntary guidelines to quiet commercial vessels by the International Maritime Organization and leading a new U.S. forum, the Subcommittee on Ocean Science and Technology Interagency Task Force on Ocean Noise and Marine Life, among other things.

The strategy suggests starting new partnerships and enlisting the help of other federal agencies, industries, academic researchers, environmental advocates and others.

The national marine sanctuaries, including the Papahanaumokuakea National Marine Monument, are expected to play a big role in the effort.

“These places are really key to improving what we know about the effects of underwater noise and highlighting new tools for measurement to get better information and improve the quality of habitat of these special places,” said Leila Hatch, marine ecologist with Stellwagen Bank National Marine Sanctuary in Massachusetts.

The release of the road map comes just a month after NOAA Fisheries released its final acoustic guidance document to better predict how man-made underwater sounds affect marine mammal hearing. The technical guidance is one example of a targeted action the road map recommends the agency conduct, officials said.

Harrison said that historically the agency has gathered a lot of science on how noise affects marine mammals. Under the new road map, she said, the agency will augment that data with a new focus on the whole “acoustic habitat.”

“Marine mammals aren’t the only acoustic-sensitive animals in the ocean,” she said.

Earlier this month at the World Conservation Congress in Honolulu, the International Union for Conservation of Nature introduced a guide outlining the best practices for seismic surveys and other forms of undersea mapping, aiming to minimize the negative impacts of loud noise on marine life.

The conference hosted several sessions dedicated to examining the impacts of human activities on the marine environment.

At the next United Nations Convention on Biological Diversity meeting in Mexico in December, governments from around the world are expected to adopt measures recommended by scientists for addressing the impacts of underwater noise on marine and coastal biodiversity.