On The Land
8 December, 2021
Redclaw offer good lifestyle and good returns
IF you have been looking for the ideal business model, one which offers insatiable consumer demand, unlimited growth potential and a quiet rural lifestyle, “Cherax quadricarinatus” farming might be the solution to your quest.
More commonly known as the Redclaw crayfi sh, these creatures tick a lot of aquaculture boxes.
They are native to Queensland, very fast growing, highly fertile, easy to harvest, can tolerate a broad range of environmental conditions, have a very simple life cycle and very few diseases or predators.
There are currently only 10 established redclaw farmers in Queensland's fledgling crayfish industry and they are centred around Gympie and the Far North.
Collectively they produce about 60 tons of product a year, which is only a drop in the potential global bucket.
Industry pioneers and production innovators, Colin and Ursula Valverde of “Aqua Verde Redclaw” Wongabel, say they cannot keep up to the demand for redclaw.
“It is only supply that is lagging and we need more farmers and more intense farm production,” he said.
Around 17 years ago, the excomputer geek and his Swissborn wife, were looking for a lifestyle change after finishing with the Department of Defence in Canberra.
They knew they wanted to live rurally and wanted to do something more meaningful with their lives.
After visiting a marron farm in Colin's home state, Western Australian, the Valverde's got excited about the concept of crayfish, but decided they wanted to farm them in the warmer, eastern states where the crayfish grew faster, reproduced more frequently and at a younger age.
After 18 months looking for the right place, they fell in love with the Atherton Tablelands and bought an abandoned redclaw farm at Wongabel.
“We wanted to have a chance to make our own mistakes, not just buy somebody else's,” Mr Valverde said.
“We didn't realise we were getting into an industry where you couldn't buy anything you needed off the shelf. We had to create everything from scratch, starting with renovating and aerating each of the 30 1000sqm ponds on our 10-hectare farm.
“There wasn't even a designated food source for the Redclaw to eat, so we approached the Rural Industries Research and Development Corporation (RIRDC) for the first of three rounds of funding, in 2007.
“We initially focused on ‘selective breeding’ and nutrition, so we could start domesticating the animals and trying to select for quicker growth. We managed to refi ne the genetics of our herd and created a new commercial grain pellet in conjunction with Advance Rural.”
For the next few years, their constantly evolving business produced 50-100 gram redclaw in earthen ponds for the restaurant trade, before eventually specialising in brood-stock development, egg and crayling production.
“This will always be a niche market product, but we needed to be able to maintain consistent supply or redclaw would be off the menu,” Mr Valverde said.
“Increasing production was our next priority and to achieve this, we realised we needed a hatchery. An out of season spawning facility which accommodated around 3000 female and 1000 male brood-stock per tank was developed to replace the pond-rearing system.”
Winter light and temperatures were manipulated inside the facility to convince redclaw that spring was imminent, bringing on early spawning.
The eggs were harvested and placed into Finnish designed hatching baskets for incubation at an optimal 26-28 degrees Celsius.
The rocking motion of the submerged baskets mimicked the natural environment the eggs experienced underneath their mother's tail, keeping them oxygenated and clean. After hatching, the eggs become stage 1 larva, and within 10 days, they moult (come out of their shell), and become a stage 2 larva.
At this point, in their natural pond environment, weighing 0.02 grams, they would leave their mother and become an independent miniature crayfi sh (crayling).
Being able to produce large quantities of “craylings”, a term created by Colin Valverde, gives farmers a faster and more evenly grown annual crop and a lot more control over disease mitigation and the life cycle of their animals.
“They can now stock an exact quantity of known-age craylings, which means they can better predict their inputs and, of course, the quantities they can deliver to the market at the end of each season,” Mr Valverde said.
“With demand for craylings skyrocketing, our farm has been supplying eggs to a company called the Australian Crayfish Hatchery, which has just started production in Townsville.
“By collaborating with them, we hope to be able to start producing tens, then hundreds of millions of craylings a year to supply global demand and aim to develop a high density nursery tailored to their requirements.
But we still have so much to learn - there is no such thing as a redclaw expert in this industry, just differing degrees of ignorance.
“We have been working on an egg counter which photographs every egg and can achieve around 99 per cent accuracy, giving us a better understanding of breeding cycles, egg development, production quantities and mortalities and we have developed an automated feeder.”
The prototype had significantly reduced the daily amount of time spent feeding.
The couple also learned that craylings grow more quickly in earth ponds than in an artificial grow space, where they cannot access all the algae, zooplankton, phytoplankton, bacteria, and fungi of their natural environment.
“But the earth tanks give us less control over the breeding process, so perhaps the answer lies in some form of hybrid combination – a more nutritious created environment,” he said.
The Valverdes have made a conscious decision not to supply to the Sydney markets, choosing instead to transport live product which retails at $22-$35/kg to local restaurants.
“We would like to transition into growing bigger crays, up to 300 grams for the premium restaurant trade.
We want to intensify production, not work harder in the coming years,” Colin said.
“We are part of a great local organisation, the North Queensland Cray Fish Association, and other producers have donated a lot of their farm resources towards the RIRDC-funded projects.
“We all pay an industry research levy now, which will hopefully attract more funding from research institutions so we can continue learning how to farm better.”
Surprisingly Colin and Ursula don't eat a lot of crayfish themselves, but when they do, they like to cook them in a mornay sauce or Swiss style, marinated in sea salt and dill and boiled for around five minutes.
