Cook Islanders grow sustainable food using 'aquaponics'

The project involves cultivating plants in water and raising fish in tanks

Flickr/ agrilifetoday

[RAROTONGA] A pilot aquaponics experiment is now underway in the Cook Islands that has the potential to become the South Pacific region's best chance for preventing food shortages.

First announced during the Pacific Islands Forum earlier this year (27–31 August), the pilot project combines aquaculture (raising aquatic animals like fish in tanks) and hydroponics (cultivating plants in water) in symbiosis, a strategy that can be replicated in other island nations.

The project's long-term objective is to give Pacific islanders — who are facing climate-related issues such as drought and fish poisoning — a way to sustainably grow crops using minimal water and no pesticides.

The Cook Islands aquaponics project was the brainchild of Pacific Islands Trade and Invest, the business arm of the Pacific Islands Forum Secretariat, which has teamed up with the New Zealand and Cook Islands governments, and with Lynnsay Rongokea and Barbara Thomson, both from the Cook Islands, to design and implement the project.

Over the past three months, the team has been successfully growing vegetables using aquaponics in a tank-like structure that emulates a natural ecosystem.

The premise of the project is simple: an attendant feeds fish in a tank, which excrete nitrate-rich waste into the water that runs through a mesh filter and irrigates plants.

Those plants filter out by-products, their roots and microbes, removing nitrates to use as vital nutrients. Once the crops have naturally filtered the water, it is aerated and re-circulated back into the fish tank.

The end products are sustainably grown fish and vegetables free from chemical contamination. The system uses just two per cent of the water used up by traditional agriculture and has zero impact on the health of the lagoon.

There is no need to discard or drain water circulating throughout the system and there is no need for chemical fertilisers, pesticides, herbicides, insecticides and fungicides.

Wilson Lennard of Aquaponics Solutions, one of the world's leading aquaponics experts involved in the project, has now returned to Australia, but will be rejoining the team in November to fine-tune the equipment and make sure the project leaders are "coping".

Thomson, one of the project's organisers, says the biggest challenge she faces is marketing. She said it is difficult to establish a client base, as most local growers have already captured the restaurant and hotel markets. Thompson says she looks forward to Christmas, when the local tomato is in short supply and she can grow tomatoes sustainably to turn a profit.

This article has been produced by SciDev.Net's South-East Asia & Pacific news desk.