They grow fast and large, so can crayfish drive Australia's next seafood boom?
They are considered a high-end "white tablecloth" product and global demand for redclaw crayfish — native to northern Australia — is growing at a rapid rate.
Now a north Queensland company in the process of patenting technology to increase hatching rates for crayfish eggs could change the face of Australian aquaculture.
Australian Crayfish Hatchery (ACF), based in Townsville, has developed an in vitro embryo incubation method for redclaw crayfish, producing thousands of juveniles each breeding.
Marine biologist Lisa Elliot from ACF said the industry's grow-out farmers had been hampered in the past by inefficient on-farm breeding processes that suffered large production losses.
"We've actually been able to take the eggs from the females, hatch them and produce craylings, baby crayfish, at a known age and number," Dr Elliot said.
"The major problem in the past was that production of seedstock was an ad-hoc affair. Mum and dad were put in ponds and the hope was they produced offspring."
Redclaw farmer Andy Gosbell, of Gympie, said the collaboration with hatcheries like ACF would be critical to the industry's growth.
"For redclaw farms to boom, and this industry will boom with this new technology, they need to go to a grow-out phase and let someone else do the breeding," he said.
"That way, you literally can do two crops a year instead of one every 12 months."
Dean Jerry, Director of the ARC Research Hub for Advanced Prawn Breeding based at Townsville's James Cook University, said the breakthrough was a big win for the industry.
"One of the bottlenecks in the past has been the production of large numbers of high-quality seedstock for aquaculture production," Professor Jerry said.
"The hatchery in Townsville will go a long way to providing a stable and high-quality supply off craylings to supply the domestic and potentially international industry.
"Like any aquaculture industry, success often depends on having access to juveniles."
Red claw opportunity
In a climate-controlled breeding facility on the outskirts of Townsville, tens of thousands of eggs are hatched to about 10 millimetres in size.
From there, farms in southern Queensland buy the craylings in where they are grown out to a table-sized product of up to 600 grams in weight.
Dr Elliot, who previously worked in prawns and marine fish industries, said the crayfish — indigenous to northern Australia — was an ideal species for aquaculture.
"They don't need a high fish-meal diet, the feed that they eat can be vegetable clippings, or detritus from the pond bottom," she said.
Mr Gosbell said the ability to move from a breeding/farming operation to solely farming would boost his production.
"I've purchased quite a few crayfish over the last couple of years," he said.
"At the moment, realistically, probably only a third of my farm is producing crayfish for sale.
"The rest is breeding ponds, egg-bearer ponds and juveniles. If I could go from two hectares of grow-out to five hectares, I could do three times the production."
Professor Jerry said the potential of the species as a growth aquaculture industry hinged on the level of investment over the coming years.
"What the industry does need is one or two champion companies to start producing the species at an industrial scale," he said.
"This will certainly help with marketing and consumer awareness of the product.
"Australian aquaculture is pretty advanced as an industry as a result of very active research and development programs.
"This has to be the way given the forces that impact on the industry including high costs of labour and operating, strict environmental compliance, international competition and high biosecurity."
Mr Gosbell said he would need to streamline and improve the grow-out process to reach the potential of his farm.
"At the end of the day, I'm trying to learn how to maximise the survival of them, they're highly carnivorous when they're little," he said.
"They're vulnerable to themselves, to dragonfly larvae, to all sorts of things that grow in the ponds.
"It could be habitat change, it could be how to start the pond with enough substrate so they can eat and be sheltered."
Mr Gosbell said he also hoped the cost of the craylings would reduce to less than 10 cents each, to cover losses in the early stages.
"I understand everyone's go to make a living. I want them to grow with us, but I think it's going to have to be a joint thing where we both grow."
Interest from the United States and China was increasing according to ACF, due to the crayfish's large size and international protein demand.
"China wants hundreds of thousands of tonnes of these animals a year and we only produce 70 tonnes in Australia," Dr Elliot said.
"They're viewed as a high-end, white tablecloth product."
While the technology to breed redclaw crayfish was utilised for commercial purposes, Dr Elliot said the process could be used for preserving endangered crustaceans too.
"The technology we're using is also able to store genetic material," she said.
"For conservation, there's quite a few endangered freshwater crayfish species across Australia, the hatchery technology can be used culture these species and conserve genetic lines."