Tuesday, February 19, 2013

Whales benefit from action on ocean noise

Scientists are working to reduce the noise levels experienced by whales from North Atlantic shipping. The blare is making it difficult for the animals to communicate with each other, which in turn is affecting their ability to find food and mates. The researchers have persuaded shipping companies to change their routes in and around the Boston area.

Sea captains use an iPad App that helps them to understand the locations of the whales and when to slow down.

The change in operations has helped to lower the din. Scientists hope it will also limit the number accidental collisions.

The waters off New England are a home to many species of whale. Many are now suffering because of increased noise levels.

Research presented at the annual meeting of the American Association for the Advancement of Science (AAAS) suggests that it has doubled each decade over the past 30 years.

The big din

Dr Mark Baumgartner of the Woods Hole Oceanographic Institution played me the sound of a passing container ship as a whale might hear it.

It was a thunderous, unchanging drone. "How would you like to have that in your bedroom, your kitchen, your work all the time?" he asked plaintively. "That's what the acoustic environment for whales is like all the time."

The effect is to reduce the range whales can communicate. "It's as if you are talking at a cocktail party and all of a sudden it is hard to hear because there is all this background noise. A couple of words get dropped, you don't get the meaning of everything that is said to you," says Dr Baumgartner. "That it what it is like for a lot of whales in the ocean right now."

There is so much commercial shipping activity and it is so loud that scientists are starting to worry about the effect that the noise is having on the whales.

Ship strikes Social communication is necessary so that they can get together for important activities, such as mating, and it is unclear just what the ramifications of cutting off that communication will mean for them.

But the ships are not just disrupting communication; they also collide with whales from time to time.

Dr Dave Wiley who works for the National Oceanic and Atmospheric Administration has seen the consequences at first hand. "Our scientists found shattered bone and large hematomas which are indicative of a ship strike," he told BBC News. Each year, there are one or two North Atlantic Right Whales stuck by ships in the area. Although that does not sound like a lot, it was enough to concern environmental groups because it is thought that there are just 500 of these animals left in the wild and mothers with calves get hit more frequently.

Whale maps

Dr Wiley and his team worked with the Boston port authorities to find a solution to the problem.

They shared their data of where the whales were and the details of the commercial shipping lanes.

Together, they worked out a new route that would reduce the co-occurrence of whales and ships by 81% and increased the transit time of ships by between nine and 22 minutes.

The new route was accepted by the International Maritime Organization, since when the ships have been using it voluntarily.

Dr Wiley also helped to develop a new iPad application that gives real-time information on the location of whales across the entire East Coast of America so that ships can avoid the large gatherings of the cetaceans.

General acceptance

Boston's vast port nestles close to the skyscrapers of the city's financial district. 1,500 vessels come in and out of here each month, mostly large container ships carrying gas and petroleum products.

Thousands of jobs depend on the commerce here, yet many companies are telling their captains to use the Whale App and the route change.

Andy Hammond, chief executive director of the Boston Harbour Pilots Association, says that the industry has realised that for a little inconvenience they can do an awful lot for whales.

"There was a little bit of resistance at first when they talked about speed reductions," he said. "Oddly enough, we found since they've implemented this, ships have slowed down an awful lot anyway. Initially, I think there was pushback but once they realised that it didn't affect this port that much, they've accepted it."

Source: BBC

Image courtesy of clarism_4 via Flickr (CC BY 2.0)