Cleaning up shrimp farm wastewater with sea lettuce

Also: why Chinese are eating even more seaweed, new government restrictions + 11 new job openings

The discharged water from shrimp aquaculture farms contains a high load of nutrients, with negative consequences for the natural environment and neighbouring shrimp farms. How to improve water quality, and at what cost, remains a vexing question for the shrimp industry.

After a decade-long cooperation with James Cook University in Queensland, Pacific Bio’s 1000-tonne shrimp farm has now found a solution that not only leaves behind clean water, but also makes money by growing sea lettuce (Ulva) that cleans the shrimp farm’s effluents in raceway ponds.

“Instead of releasing wastewater, we’re actually able to bring it back into the system. That means less need to pump water in from the reef, and as a result, significantly less chance of introducing a biosecurity hazard, such as the highly contagious viral white spot disease, which can decimate farmed prawn populations.“

The sea lettuce is then turned into a biostimulant called PlantJuice, opening up a new revenue stream. Read the whole story at EvokeAg.

Novel foods

Born Maverick (N. Ireland) has developed a prototype for highly realistic vegan shrimps and scallops made from seaweed.

Dutch Seaweed Group, SeaFlavours and SeaWeed-Tech collaborated to create drop-in frozen seaweed cubes for food producers.

In China, seaweed consumption continues to grow due to easier access (urbanisation) and increased dietary knowledge.

Start-ups entering incubators

Incubator season has started.

ReShore, the living breakwater start-up, enters leading agrifoodtech accelerator Startlife and gets a grant from the Dutch Research Council.

3 seaweed start-ups enter the Sustainable Ocean Alliance incubator’s latest cohort: Sway (bioplastics), Oceanium (bioplastics) and Seaforestation (marine permaculture deepwater solar irrigation - if you are not sure what that means, that makes two of us)

Serial incubator entrant B’Zeos (previously at Blue Bio Value, Sustainable Ocean Alliance, EIT Food Accelerator and EIT Climate-KIC) will now continue its seaweed bioplastics research at the new Nestle-sponsored FIT Food Tech program.

Grant funding millions

Cascadia Seaweed was awarded USD 1.4 million in grant funding from the BC Salmon Restoration and Innovation Fund to cultivate 400 ha of kelp beds to evaluate their effect on juvenile salmon.

Oceanium got 2 million euros from the European Maritime and Fisheries Fund to develop its seaweed biorefinery concept.

South Australia’s seaweed sector got a USD 1.1 million boost.

The Nature Conservancy is helping serial defaulter Belize buy back its debt at a discount, in return for ocean protection measures. Here is how their Blue Bond scheme works.

Governments restrict

“We didn’t realize the extent to which this stuff does have biological value," he said. "And so it caused us to take a step back and say, ‘Maybe we shouldn’t allow people to take whatever quantity they want from wherever.’” - Alaska limits seaweed harvesting

On a related note, the California Department of Fish and Wildlife (CDFW) is recommending that the state temporarily close or cap bull kelp harvest to counter the disastrous decline of kelp forests.

In India, a farming project that aims to produce 30,000 tonnes of seaweed a year has been launched in the Lakshadweep archipelago.

Conservation: only bad news

Evidence is compounding that after California, the kelp forests of the North Pacific are next to be decimated by an onslaught of urchins.

The picture is looking equally bad in Australia, where urchins are marching south. It’s the same story in New Zealand.

11 new job openings at seaweed companies

If you have a job opening you want to see mentioned here, get in touch.

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