Seismic testing may impact spawning patterns of fish and mammals

Published on October 25, 2012

Seismic testing involving loud airgun arrays, used to find deposits of oil and gas in the sea bed, may be used off the east coast of America next year. Environmental campaigners are trying to prevent this due to its effect on marine wildlife.

Seismic airguns drive away marine animals and may also cause damage to dolphins and whales. The guns discharge compressed air into the water column at 10 second intervals around the clock for weeks at a time. This is accompanied by a deafening sound that impacts marine mammals which rely on sound to navigate, find food and communicate.

The Department of the Interior in the USA will decide early in 2013 whether this type of testing will be approved for use off the Atlantic coast. A moratorium has been in place for over twenty years, forbidding oil exploration in these waters, but this was lifted by President Obama in 2010. Conservatively, there are estimates that “138,500 whales and dolphins will be injured as a result.”

This type of testing is also thought to impact fishing on cod and haddock. Catches decreased by 40-80 % in Norway after seismic airgun tests during 2008. Fishermen there claim that spawning patterns were affected. These tests scare fish away by distances of between 5 to 33 kilometres, leading to lower catches once closed spawning areas are reopened for fishing.