In a lab in Hobart, scientists haven’t been able to answer one of the crustacean world’s curlier questions: can lobsters hear?
- Southern rock lobster fisherman fear plans to use seismic testing to look for oil and gas reserves in the Bass Strait could threaten crayfish populations
- For years cray fishermen and other aquaculture industries have made anecdotal reports of impacts on fish stocks following testing
- The science is still unclear but a Senate inquiry is looking at the issue
It doesn’t sound like a terribly important pursuit, and as Dr Ryan Day explains the answer is also proving elusive.
“Funnily enough, with the lobsters we work on we don’t know whether or not they can hear,” he said.
Even more oddly, science has been able to establish that lobsters can make sounds as they traverse their underwater reefs.
“So they make noise. It may be for predator deterrence or it may be communication between them, we’re not really sure,” Dr Day said.
It’s the hearing systems of lobsters, though, that could have huge ramifications for two industries pitted at odds in Bass Strait off the southern shores of Australia.
On one side is the seafood industry, which counts southern rock lobster, giant crab, scallops and squid as its prize exports.
On the other, is the oil and gas industry which wants to use seismic testing to map the seafloor to help boost stocks for vehicles and industry.
Seismic testing involves the use of airguns to release large blasts of low-frequency sound down to the sea floor.
As the sound bounces back, it is used to map areas of potential undersea reserves.
For years, fishermen such as Paul Jordan have been reporting their catch as severely reduced in some areas after a seismic mapping ship with airguns off the back has passed through.
“Many years ago, we were having one of the best years of our lives that we’d seen in the giant crab fishery. It was just phenomenal numbers,” Mr Jordan said.
“We were literally catching hundreds.
“We’d gone to catching single figures and we looked into it and we didn’t know what had happened — anyway, there’d been seismic testing in Bass Strait.
“We don’t think it could have been anything else. Everything else was sort of the same.”
Life cycle of lobster behind cost and threats
Tasmanian Seafood and Industry Council chief executive Julian Harrington said Mr Jordan was not alone.
“My members have always talked anecdotally about the impact of seismic [testing], they’ve talked about a seismic survey going through, and they couldn’t catch lobster on this reef, but they did on that reef,” he said.
In the debate, it is important to remember that it takes at least five years for a lobster to go from an egg stage to maturity.
It is what makes them so expensive, but it also means they spend many years as vulnerable larvae so fine they are hard to see floating around the ocean.
Any impact on the larvae by seismic testing today can have long-term ramifications for the industry years down the track.
“It’s our members who feel that impact in six or seven years’ time,” Mr Harrington said.
“The oil and gas will be long gone. Our members will be left to pick up the pieces.”
From snapper in WA to lobster off Tasmania
Such has been the growing level of concern that there is a Senate inquiry into the issue.
Inquiry chair Greens Senator Peter Whish-Wilson established it after being contacted by a snapper fisherman in Western Australia.
Senator Whish-Wilson said the inquiry heard there had been a rush of applications for seismic testing around the country, something the industry disputes.
“They literally just can’t keep up with the volumes of applications,” he said.
“There’s a lot of activity occurring, including in new areas of seismic testing, such as off the west coast of King Island, off the coast of Newcastle in New South Wales, off the Otway Basin in South Australia and off Western Australia.”
Senator Whish-Wilson pointed out countries like New Zealand had already banned new applications as they move to a carbon neutral economy.
“I think it’s really important that we put a halt to these activities to have a much better research evidence-based approach to regulating seismic testing in Australia,” he said.
Exposed lobsters slower than non-exposed, research shows
Marine scientists believe the jury is still out on whether these powerful low frequency sounds affect marine life, but say the evidence is mounting.
While they have not been able to establish whether lobsters can actually hear these blasts, what they have been able to work out is that they do impact the lobster equivalent of an inner ear, called a statocyst.
Their research has shown lobsters exposed to the soundwaves have trouble turning over if they accidentally fall on their back.
“We found a significant impact in that exposed lobsters were slower than non-exposed lobsters,” Dr Day said.
“It shows that their ability to do simple reflexes has been compromised.”
They have also demonstrated impacts on their blood cells and immune system.
More concerning to them is that seismic testing has been shown to kill some plankton.
Larvae in the ocean eat plankton, and because lobsters take up to five years to reach maturity, they spend a long time as larvae.
Seismic testing was also linked to a large scallop kill in the Bass Strait in 2011, which prompted an earlier Senate inquiry and there is now a research focus on its potential impacts in squid populations.
Ensuring supply for the long term
The fishing industry says it just wants the oil and gas industry to come to the table.
Mr Harrington said they would like to see the survey site moved further away from known fishing spots, and an offset fund established to help cover any losses to industry and pay for more research.
“For highly productive areas we would certainly like to be able to sit down and try and come to some compromises around staying off our turf,” he said.
The industry said it was taking the research seriously and has been working with fishing groups.
Andrew McConville, the chief executive of Australian Petroleum Production and Exploration Association, said seismic surveys had been done around the continent for six decades.
“There’s been more than 1,500 seismic surveys done in Australia, we’ve mapped more than 3 million kilometres of coastline.”
Mr McConville said using sound to map reduced the amount of physical drilling the industry needed to undertake and ensured minimal environmental impact.
Testing was also heavily regulated and environmental plans had to be developed for every proposal.
And while there had been a downturn in exploration, Mr McConville said the industry was trying to turn that around as Australia moved towards a potential gas-fuelled energy future.
“We’re actually trying to work with the government to look at ways in which we can encourage exploration, because we know that we have a magnificent resource here in Australia,” he said.
“Demand for these products will continue, well out beyond 2040.”
Mapping, mapping and more mapping
Then there is the role of the federal regulator, the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA).
Fishermen have asked why company after company needs to re-explore the same area and mapping is not simply registered with the authority and shared.
“Our members continually question: ‘Why do you always have to go back and get more data? Why can’t you share the data amongst companies?’,” Mr Harrington said.
A department spokesman said the logging and sharing of the results of seismic surveys was managed by a different department, the National Offshore Petroleum Titles Administrator (NOPTA).
“Offshore seismic [testing] is a competitive industry and the current licencing system allows multiple proponents to apply for licences to conduct seismic surveys over the same area. NOPSEMA is not involved in this process.”
Th spokesman said it was up to date with current research and its experts assessed all potential impacts testing would have on marine life.
Surveys could be changed, reduced and in some cases rejected depending on the application, he said.
It was also investing in more research and he noted that “many, but not all, seismic surveys occur in deep water away from sensitive marine species”.
From the sea floor to the dining table
It comes after a difficult year for the lobster industry which had its exports to China hit hard by both the coronavirus pandemic and trade disputes.
No matter the outcome, restauranteurs say any hit to the lobster industry will hurt.
Will Mure runs Hobart’s famous Mure’s Upper Deck and says tourists come to the restaurant just to try southern rock lobster.
“If the supply is not there, that demand goes up and prices become higher and higher,” Mr Mure said.
“Something like the seismic surveys that could potentially kill these animals would be a disaster.”
For second-generation fishermen like Paul Jordan, they just hope authorities do enough to protect lobster reserves into the future.
“As lifelong career fishermen we care about the ocean and the marine environment probably more than most people,” he said.
“I’d like to think there’d be something there for my children.”