Noise Pollution Pose Serious Problem to Endangered Orcas

The sound emitted from large commercial ships is wreaking havoc to the Pacific Northwest killer whale population, negatively affecting their ability to communicate with one another and find food reveals a new study published in the journal PeerJ.

Cargo ships, oil tankers and commercial container vessels emit a considerable amount of noise under the sea which consequently drowns out the communicative sound signals used by killer whales, also known as orcas. The underwater noise pollution significantly lowers the ability of the endangered mammal to detect their primary source of sustenance, the Chinook salmon. 

"The most subtle sound they are probably trying to hear is the sounds of their echolocation clicks bouncing off a salmon," said oceanographer Scott Veirs. "Like bats, they're listening for very faint echo from their prey." The loud sound produced by commercial vessels overrides the sound frequencies emitted by the salmon.

The research was conducted in the Haro Strait, a waterway that lies near Washington's San Juan Island, by a team of scientists who measured the noise emitted by commercial and military vessels and their impact on the endangered orcas that inhabit the surrounding waters. It was found that apart from acting as a serious deterrent from finding food, the din of ships also affect the general well being of the killer whales.

Causing more worry to the researchers is the fact that Chinook salmon are also endangered in the region, and a decline in their population along with the orcas' inability to find them can have serious implications to the species' survival. The research holds the key to potential answers conducive to the welfare of killer whales

A solution to the problem of ships interfering with underwater soundscape is yet to found. However, commercial ships and military vessels can lower the volume of their din by slowing down their speed.