Opinion: Careful exploration and development of our natural resources can benefit New Zealand
While these surveys have been happening for decades around New Zealand, it's worth outlining exactly how they work.
The surveys use soundwaves to produce detailed images of the various rock types and their location beneath the earth's surface. This information can tell us the location and size of possible oil and gas reservoirs without having to disturb the land or seabed.
Overall it has very minimal effects on the environment and like all activity in our industry, it is closely regulated and monitored.
The Department of Conservation has a detailed Code of Conduct for minimising acoustic disturbance to marine mammals which is strictly followed.
As part of this operators have to verify the emitted sound levels are compliant with thresholds in the Code before they even begin work.
All survey vessels use Passive Acoustic Monitoring systems (PAM) which operate 24 hours a day to detect and track marine mammals like whales and dolphins.
There are also two independent visual observers onboard every vessel, and operations are stopped immediately if any mammals enter the set mitigation zones.
Overall the sound generated by seismic acoustic work is around 230 to 255 decibels which is a similar level to some naturally occurring sounds.
The sound also dissipates rapidly in the water - at one kilometre from the source the sound levels have generally dropped below 171 decibels, which is lower than the noise from large commercial shipping vessels.
All observer reports are submitted to the Department of Conservation, and are made available to any researcher who requests the data.
After decades of use there is no clear international evidence to suggest marine life are impacted by these surveys.
By and large, we shouldn't underestimate the intelligence of animals like whales and dolphins. If they don't like the sound coming from a vessel then they swim away. In fact there is plenty of anecdotal evidence from observers of dolphins investigating and playing around the vessels.
Our industry takes the ocean environment very seriously. As well as operating very carefully, many companies are also conducting their own research into marine mammal distribution.
We strongly support evidence based science, and are always open to new information. We want to be open and transparent, and provide all the facts - not just selective ones - so that people can make up their own minds.
Amanda Larsson from Greenpeace (Taranaki Daily News 15 November) also asks why we need to search for natural resources like oil and gas.
The answer is that New Zealand has great potential to find and produce more natural gas which has half the carbon footprint of coal. This could be exported overseas, helping lower global emissions and giving a real boost to the New Zealand economy at the same time.
Stopping exploration and production in New Zealand would have little impact on global emissions because production would simply shift elsewhere in the world, potentially to countries with lower environmental and social standards.
This could well be worse for the global environment if other sources of energy were used (such as coal) instead of natural gas
We would also miss out on the economic benefits which could be significant, as shown by the recent report into the Barque prospect off the coast of the South Island.
New Zealand Oil and Gas estimate this prospect off the coast of Oamaru could generate $32 billion in taxes and royalties for the Government over the life of the field.
All of this reinforces the need for careful exploration and development of our natural resources to benefit New Zealand, and the world.
You can find more background on how seismic surveys work at our website here: http://www.energymix.co.nz/our-process/seismic-surveys/
Cameron Madgwick is the CEO of the Petroleum Exploration and Production Association of New Zealand (PEPANZ).