Scientists urge end to seismic tests to protect rarest dolphin

Maui's dolphins need seismic ban
April 2013. In a letter to New Zealand's Prime Minister, the Society for Marine Mammalogy (SMM) urges the NZ government to immediately halt seismic testing in Maui's dolphin habitat.

Seismic surveys
With a membership of some 2,000 scientists from 60 countries, the SMM is the world's largest professional body dedicated to research on marine mammals and the ecosystems that support them.

The SMM's letter is concerned with seismic surveys off the west coast of New Zealand's North Island, which is the final refuge of the little known Maui's dolphin, the smallest and rarest dolphin on earth. The SMM states that allowing seismic testing in the dolphins' habitat may harm their hearing and push them into unprotected areas, where they are more exposed to fishing nets.

Fishing is the primary cause of death
Fishing is the primary cause of death among the last 55 surviving Maui's dolphins. Gillnets and trawling kill about nine percent of the population a year - that's 75 times more than the sustainable limit.

The SMM highlights that a proposed seismic project in the US was rejected because of its expected impact on an otherwise unthreatened population of more than 2,000 porpoises. The impact on the last 55 Maui's dolphins could be devastating.

"Allowing this seismic testing thus appears inconsistent with the New Zealand Government's stated goal of enabling this subspecies to recover," writes SMM President Professor Helene Marsh.

Seismic testing involves shooting noisy blasts of compressed air towards the ocean floor every 15-20 seconds, around the clock, for weeks or months. These airgun signals are loud enough to penetrate deep into the ocean floor to reveal buried reservoirs of oil and gas. Airgun blasts are known to affect whales, dolphins, and porpoises and can also disturb and harm the fish they feed on.

"Twenty-four cetacean species have shown negative effects to marine noise pollution," says NABU International's Head of International Species Conservation, Dr. Barbara Maas.

"Noise is a well-known stressor, not just for marine mammals. This means seismic testing is potentially dangerous, even if it doesn't kill the dolphins outright. Chronic stress can heighten susceptibility to other threats and slow down population recovery by suppressing reproduction and the immune system. It can even harm unborn dolphins prenatally, all of which Maui's dolphins can ill afford."

Continued: http://www.wildlifeextra.com/go/news/mauis-seismic.html