Aquaculture Explained: Cultivating Laminaria digitata

In the past two decades, there has been much debate amongst industry, the state development agencies and the research institutions about the potential of the Irish seaweed sector. Seaweed gathering and processing is a traditional activity in Ireland bringing economic activity and employment to coastal communities. Ireland’s seaweed and biotechnology sector is currently worth €18 million per annum and employs 185 full time equivalent people (Morrissey et al., 2011). The potential to increase employment, exports and wealth from seaweed in Ireland was looked at by the National Seaweed Forum which was established in 1999 to join industry with research bodies, state agencies and departments to make recommendations for the future development of the industry. 

One such recommendation was the development of seaweed cultivation. With this in mind, groups such as Bord Iascaigh Mhara (BIM), Taighde Mara Teo (TMT), National University Ireland Galway (NUIG) and Queen’s University Belfast (QUB) initiated seaweed cultivation trials. These early trials had varied success and allowed for experimentation and year-on-year technique improvement. Farming seaweed as opposed to simply gathering seaweed requires a thorough knowledge of seaweeds and perfect manipulation of the seaweed life cycle. Mastering this has concerned Irish seaweed researchers and industry practitioners alike over the last decade. 

The Seaweed Hatchery project has focused on developing new techniques, and improving existing knowledge of seaweed cultivation. This manual is one such output of the project. The manual is offered to the industry as a guide to the hatchery techniques required to develop new aquaculture opportunities for Laminaria digitata. 

As with all BIM ‘Aquaculture Explained’ manuals, it is based on the research and experiences of the group and includes both hatchery and sea trial cultivation results obtained over several years and sites. An attempt has been made to provide an easy to use document filled with practical advice for those interested in growing kelp.