Tests ‘damage’ lobsters
FRIDAY, JULY 26, 2019 themercury.com.au SUBSCRIPTIONS 1300 696 397 SEISMIC airguns used to conduct geological surveys of the seafloor inflict permanent harm on rock lobsters, new research has found.
The finding has prompted a call for a halt to seismic testing due to be carried out in Bass Strait within weeks.
Scientists from Tasmania’s Institute for Marine and Antarctic Studies and the Centre for Marine Science and Technology at Curtin University have found that the sensory organs and righting reflexes of rock lobster can be damaged by exposure to air gun signals.
Seismic testing is commonly used by the oil and gas industry to look for undersea deposits. It involves the repeated blasting of the seafloor with soundwaves from highpowered airguns.
The study, p
Lead author Ryan Day said researchers exposed rock lobster to seismic air gun noise during field tests in Tasmania’s Storm Bay and examined the effects on a key sensory organ, the statocyst, and the lobsters’ reflexes.
“While the impact of air guns on whales and fishes has been relatively well-studied, the effects on marine inverte
brates such as lobsters, crabs and squid remain poorly understood,” Dr Day said.
“We chose to study the impact on rock lobster because they are a high-value fishery and an important part of global marine ecosystems.”
The testing showed that the statocyst, a sensory organ on a lobster’s head which is critical in controlling their righting reflex, was affected by exposure to seismic airguns.
“After exposing lobsters to the equivalent of a commercial air gun signal at a range of 100-150 metres, our study found that the animals suffered significant and lasting damage to their statocyst and righting reflexes.
“The damage was incurred at the time of exposure and persisted for at least one year — surprisingly, even after the exposed lobsters moulted,” Dr Day said.
The study is the latest in a series which has shown marine animals — including scallops and zooplankton — suffer physiological damage from noise such as seismic surveys.
Seismic testing for oil is scheduled to begin off King Island on September 1.
Greens Senator Peter Whish-Wilson said it should not go ahead.
“The report again highlights the madness of releasing new acreage for oil and gas exploration off the cost of King Island, a prime spot for rock lobsters,” he said.