Greenpeace and other anti-oil lobbyists have been accused of using bogus science in their attacks on the oil industry.
They are charged with claiming deep sea oil quests harm marine mammals when there is little evidence supporting this.
The accusation came at an energy conference in Auckland.
A long time member of the oil industry, now working for an Australian consultancy, John Hughes told the conference it was simply incorrect to suggest deep sea oil searches harmed mammals such as whales.
He said years of exploratory operations off the coast of North West Australia have had little effect on marine wildlife.
"They are certainly not damaging like the NGOs claim. We have 40 years of evidence now, the humpback populations for example on the North West Shelf increasing at a biological maximum."
The focus of the environmentalists' claims is that during oil surveys, compressed air explosions are set off underwater, the sound waves bounce off the earth's crust and the returning wave gives some clue as to what is down there.
Environmentalists said this noise harmed whales and other species.
Mr Hughes said noise from these explosions was attenuated by their passage through water and at 68 metres would be no louder than the sound of a whale breaking the surface of the ocean.