Marine seismic surveys used in petroleum exploration could cause a two- to three-fold increase in mortality of adult and larval zooplankton, new research published in leading science journal Nature Ecology and Evolution has found.
Scientists from the Institute for Marine and Antarctic Studies (IMAS) and the Centre for Marine Science and Technology (CMST) at Curtin University studied the impact of commercial seismic surveys on zooplankton populations by carrying out tests using seismic air guns in the ocean off Southern Tasmania.
The research found that the air gun signals, commonly used in marine petroleum exploration, had significant negative impact on the target species, causing an increase in mortality from 18 per cent to 40-60 per cent.
Impacts were observed out to the maximum 1.2 kilometre range tested, 100 times greater than the previously assumed impact range of 10 metres, and all larval krill in the range were killed after the air gun’s passage.