Seismic Blasts Used to Find Oil Can Blow Massive Holes in Plankton Populations
Using bursts of sound to explore the ocean floor for signs of oil deposits has been shown to kill microscopic plankton more than a kilometre away.
The new research expands estimates on how far the lethal impact of the blasts could reach, and adds yet another concern to the growing list of risks seismic surveys poses on marine life.
Since the late 1960s, surveyors have used bursts of compressed air to map the geology of the ocean floor, bouncing a series of sound-waves up to 255 decibels in volumebetween a boat and the rock below in search of underground resources such as oil deposits.
The practice has long been controversial, with mixed evidence on the extent of the impact such loud noise has on fisheries, marine mammal migration, and other components of the surrounding ecosystems.
At its worst, the blasts could be causing significant distress to whales and dolphins up to 70 kilometres (44 miles) away, who rely on sound to communicate over long distances.
There is some speculation that the use of air guns could even be behind a number of beach strandings, and evidence of damage to fish up to several kilometres away, and potentially be causing harm to turtles and large marine invertebrates such as squid.
Oddly, little research has been done on the physical damage being done to the lower rungs of the marine food chain – the zooplankton.
This research was published in Nature Ecology & Evolution.
