A West Wales seaweed and shellfish farming operation has received approval to expand two marine farms following a licence extension from Natural Resources Wales.
Câr-y-Môr, a community benefit society with approximately 700 members, aims to provide British land farmers with a homegrown fertiliser substitute as Middle East conflict drives up synthetic fertiliser costs. The expansion will create eight new positions over five years, joining the 19 full-time workers currently employed at the St Davids site.
In March, Câr-y-Môr published results from seaweed biostimulant trials funded by the Co-op Foundation’s Carbon Innovation Fund. Results showed that cutting synthetic fertiliser by 40% while applying the seaweed biostimulant maintained grass quality and increased yield by 29% on conventional grassland. Cereal and potato fields maintained yield and quality when fertiliser was reduced by 25% and 29% respectively.
Earlier trials demonstrated a 24% yield increase on organic potatoes and an 18% yield increase on silage, equivalent to £92 per hectare, when the biostimulant was added to existing fertiliser programmes.
The community business has entered its third year of seaweed biostimulant trials and secured permission to expand two existing integrated multi-trophic aquaculture (IMTA) sites in Ramsey Sound off Pembrokeshire. This enables increased Welsh seaweed production and meets growing demand for shellfish, which rose 30% last year.
“NRW’s approval reflects years of collaboration between our team, volunteers, and stakeholders, along with strong backing from local residents and businesses,” said Beth Marshall, Câr-y-Môr’s marine biologist who led the licence application. “It gives us scope to harvest more zero-input seaweed for land-based biostimulant, increase shellfish and seaweed production in A Grade waters for our 90-plus restaurant partners, expand community education programmes, and create additional year-round roles in rural Pembrokeshire.”
The expanded sea farms will total 8 hectares, cultivating sugar kelp, oarweed, Atlantic wakame, furbelows, dulse, pepper dulse, sea lettuce, scallops, native oysters, and mussels. The licence extension coincides with the opening of the Sied-y-Môr facility, home to Wales’ first dedicated seaweed biorefinery.
The community business has also participated in a native oyster restoration programme, deploying 50,000 native oysters into Pembrokeshire’s Daugleddau Estuary last year.
“This decision represents a vote of confidence in regenerative sea farming and reinforces the importance of long-term, responsible marine resource use in Wales and across the UK,” said Sophie Wood, programme manager at the UK Seaweed Network.
Jess Watton, education and engagement lead at Câr-y-Môr, has conducted seaweed workshops reaching more than 4,000 schoolchildren. “St Davids sits on the edge of west Wales, famously the smallest city in the UK. Yet our community is pioneering regenerative ocean farming, linking aquaculture with agriculture and promoting Welsh seafood,” she said.