Human Noise Pollution Killing Conversations in the World's Oceans
By partnering with Cornell University and others, IFAW is working to better understand how sounds of ships, sonar and oil exploration are affecting whales, dolphins and other marine animals. The results are sobering, as several recently-released acoustic maps illustrate. Large ships are literally drowning out the calls of critically endangered right whales.
Underwater, sound waves travel much further than light. As a result, hearing is more important than seeing for many marine animals. Whales, dolphins and their aquatic brethren rely on sound to communicate, find food, avoid predators and “see” the world around them (eg. sonar). The ocean is filled with the sounds of these animals, much like a springtime meadow is filled with birdsong. But underwater sound involves more than listening. Animals actually feel the sound, much like we feel the thumping of bass on a loud stereo. Marine animals use sound — hearing and feeling it — to explore their world.
The system has worked well for eons. But no longer. In recent decades, the marine world has been taken over by an unceasing din of submarine sonar, oil exploration, ship propellers and undersea construction. Many areas have seen underwater noise levels increase more than ten times since the 1960s. Try doubling the volume on your stereo, and you’ll quickly see why a ten times increase in volume is a bad, bad thing. At these volumes, we aren’t talking about just noise. We are talking about noise pollution.
The trouble with too much noise — noise pollution — is how it affects many marine animals. Human-generated noise drowns out “conversations” between whales. It lessens the effectiveness of dolphins’ sonar, making it harder for them to find food or evade predators. Some areas are so loud that resident whales, dolphins and fish simply leave. This is a problem anywhere, but is especially concerning where unbearable noise levels intersect with critical wildlife habitat.
This is why IFAW partnered with Cornell University, and others, to accurately measure sound levels in Stellwagen Bank National marine Sanctuary, an important right whale feeding habitat off the coast of Massachusetts. As a result of this work, we now know right whale calls in the Sanctuary are regularly drowned out by commercial shipping traffic. Check out the pair of maps in a recent National Geographic article to get an idea for how overwhelming the sounds of these ships can be. Cornell also has a pair of great maps on their website.
Although ocean noise pollution is not a new problem, we are only now beginning to understand just how pervasive and damaging it can be. If whales and dolphins can’t hear, they can’t navigate their world. They can’t eat. They can’t find one another to breed or raise their calves.
Here at IFAW, we will continue to support research into oceanic noise pollution and curb excessive noise in sensitive areas. Because, the more we learn about this issue, the clearer it is that this is nothing we can turn a deaf ear towards. And, the more we know, the better able we will be to help.
For more information on the International Fund for Animal Welfare efforts to save animals in crisis around the world, visit http://www.ifaw.org