Seaweeds harvested in Ireland have traditionally played a role in food products and in fertiliser products, but a new seaweed cultivation project has already demonstrated how this dynamic natural resource can be produced more effectively. The project aims to provide essential research data on the cultivation of three popular seaweed species to assist in the growth of the Ireland’s seaweed industry.
The project research group, coordinated by BIM, is a diverse collection of academic and industrial partners including Queen’s University Belfast and the National University of Ireland, Galway with close collaboration from Irish seaweed companies – Cartron Point Shellfish, Tower Aqua products, Dolphin Sea Vegetable, G and B Barge Operators, Roaring Water Bay Seaweed Cooperative Society and Cleggan Seaweeds. The group’s final report will provide the necessary data to enable industry to grow a relatively small niche sector with a current estimated output of Eur10 million annually to an output of Eur20 million by 2013.
During the three year project, the group aims to grow three valuable species of seaweeds on a pilot or commercial scale in sea sites all around Ireland. The species being farmed include two red seaweeds ‘dillisk’ (Palmaria palmata), and (Porphyra sp.), or ‘nori’ in Japanese and a brown seaweed ‘kelp’, (Laminaria digitata). Cultivation of these seaweeds requires a laboratory or ‘hatchery’ phase, followed by an on-growing phase at sea. Hatchery procedures for all three species are currently being perfected in Portaferry Marine Laboratory, Co. Down; Martin Ryan Institute, Carna in Co. Galway and the Daithi O’Murchu Marine Research Station at Gearhies, West Cork.
Two and a half years into the project; and the first results are starting to be produced from these sites. In the South-West, Laminaria digitata has been grown very successfully on longlines in Roaring Water Bay. The harvesting of these longlines in the near future makes this the first pilot-scale harvest of cultivated Laminara digitata on longlines in Europe. Typically dried and packaged Laminaria digitata can demand 10-16 euro/kg for bulk quantities. This price represents the higher end of the market for this product.
Another exciting first for the research group is the successful growth of Palmaria. In preparation for the on-growing period at sea during winter 2010, the team have been working through the reproductive season to build up stocks of seeded material of Palmaria. Altogether, they currently hold over a kilometre of seeded Palmaria string, making this the largest concerted effort for growing this species yet. This is also the first time that Palmaria has been grown using vertically deployed nets as opposed to deployed droppers.
Plants grow very vigorously on the nets to give the appearance of a ‘seaweed curtain’ in the water. This new technique demonstrates the move away from experimental trials to a larger, more commercially viable method of cultivation. The total biomass produced on these nets will be calculated in the next two months. Currently wild sourced dried and packaged bulk Palmaria is being sold at 16-19 euro/kg.
Porphyra, which is a European ‘nori’, is extensively cultivated in Asia and the delicious dark-red paper-like end product is used for sushi rice wraps. It is the most valuable seaweed food product and highest quality nori can fetch up to 162 euro per 100g of toasted nori sheets. Porphyra has a complicated life cycle, which makes it a potentially more difficult and more expensive species for aquaculture.
No native Irish species have ever been tested before in cultivation trials. During this project, a native species is being tried in the North for potential cultivation in Strangford Lough. These are the first trials of its kind in Ireland and the UK. However, more research is needed to establish this native Porphyra species for large-scale aquaculture.
It is clear from the results so far, that seaweed offers huge potential for Irish aquaculture and its versatility lends itself to a diverse range of sectors from functional foods and pharmaceuticals and as well as horticulture and as a food source.
Pictured at the launch of a new seaweed cultivation project are: Minister of State at the Department of Agriculture, Fisheries and Food, Sean Connick, TD; Lucy Watson, BIM; Dr Astrid Werner, Queen’s University; and Dr Maeve Edwards, NUI, Galway.