Noise pollution drowning out world’s marine mammals
The report, Ocean Noise: Turn it down, highlights how steadily increasing man-made noise - particularly from shipping, sonar and seismic surveys - is interfering with marine mammals’ communication, dramatically altering their behaviour and injuring and even killing some whales and dolphins.
“Humanity is literally drowning out marine mammals,” said Robbie Marsland, Director of IFAW UK. “While nobody knows the precise consequences for specific animals, unless the international community takes preventive measures we are likely to discover only too late the terrible damage we’re causing.”
Ocean noise has doubled in each of the past four decades according to one Pacific study*. The world’s 100,000-strong commercial shipping fleet is identified as the biggest single man-made noise generator - and IFAW warns that by 2025 the gross cargo tonnage shipped internationally is forecast to double or even triple.
The report follows growing concern about ocean noise pollution from scientists and international bodies including the United Nations. It reveals that man-made noise is already making it harder for marine mammals to use their own sounds or echo-location to find food, prey and mates, to navigate and form group bonds.
The report also tells how ocean noise pollution is causing marine mammals to abandon habitat and vital activities such as feeding, as well as altering their surfacing and diving. Some whales have been forced to change their calls as they struggle to make themselves heard and the distance over which blue whales can communicate has been reduced by a staggering 90%.
IFAW’s ocean noise report especially condemns high intensity
sound sources as a major threat, such as seismic surveys and military sonar used
by the world’s navies to detect submarines. The colossal sounds these emit, well
over 200 decibels, can injure marine animals and damage their hearing. High
intensity sonar has also been linked by scientists to many fatal strandings of
whales and dolphins. The stranding and deaths of 26 dolphins in Cornwall in June followed
a Royal Navy exercise nearby, although no specific cause has yet been revealed.
Post-mortem results are expected this autumn.
Download the report
Notes to Editors:
The UK and US navies have acknowledged the threat to marine life from high intensity sonar and accept the need for mitigation measures, such as stopping transmission if whales are seen close to the ship. IFAW believes these measures are largely ineffective as visual monitoring measures introduced during naval exercises to detect beaked whales – the species about which there is most concern – are likely to detect fewer than two per cent of those whales directly in the paths of ships.
IFAW’s report makes a raft of recommendations aimed at governments, international bodies, the shipping industry and all ocean users to reduce noise and marine animals’ exposure to high-intensity sounds. They include calls for awareness raising, codes of conduct and enforced regulations within national and international legislation. IFAW is also calling for loud sound sources such as seismic airguns and sonar to be prohibited in sensitive and protected areas designated for marine species that are vulnerable to ocean noise pollution. The UK Government should also use the opportunity of the Marine Bill, currently under consultation, to take action on ocean noise. IFAW also believes noise should be a key consideration in the design of all vessels, from supertankers to jet skis.
* McDonald et al, 2006