Development and application of traceability tools for Irish shellfish and fish of economic and conservation concern (TRACE-FISH)

Irish name: Diúilicín

Scientific name: Mytilus edulis

Blue mussels are filter-feeding bivalve molluscs found on shores across the world’s temperate coasts. They feed by pumping large amounts of water over their gills and can filter up to 65 litres of water per day. As filter feeders, mussels feed on plankton which can sometimes include naturally occurring phytoplankton that produce toxins which have the potential to be harmful if consumed. The Marine Institute run a biotoxin monitoring programme to ensure that toxicity in shellfish production areas is detected before harvesting to prevent the placement of contaminated produce on the market. Blue mussels are a popular and nutritious seafood choice, making up the largest aquaculture sector in Ireland in terms of volume produced. In 2022, 17,100 tonnes of blue mussels were produced in Ireland, valued at an estimated €17 million. As such, the mussel aquaculture industry remains an important source of income for rural coastal communities nationwide.

Irish name: Oisre

Scientific Name: Crassostrea gigas (Pacific oysters) and Ostrea edulis (Native oysters)

Oysters refer to several different species of filter-feeding bivalve molluscs, often regarded as a delicacy among seafood consumers. They are profound filter-feeders, filtering substantially more than blue mussels at over 150 litres of water per day. Much like other filter feeding bivalves, they are known to accumulate contaminants from the surrounding environment in their tissues. Therefore, toxicity levels in oyster production areas are similarly monitored by the Marine Institute. In Ireland, two species of oysters are commonly grown and consumed: Pacific (sometimes referred to as rock oysters) and native oysters. As its name suggests, Pacific oysters are native to the Pacific coast of Asia, but have been introduced to many areas of the world including along the Southern African and European coastlines, where they are cultivated. As such, they are recognized as the most widely transplanted shellfish globally. Native oysters are native to Europe and hold considerable cultural significance in Ireland, where its harvesting is known to have supported coastal communities for centuries. Oysters are the second most economically valuable aquaculture species in Ireland, second only to Atlantic salmon. In 2022, 11,000 tonnes of oysters were harvested in Ireland, valued at an approximately €51 million. The majority of this was derived from Pacific oysters, which are farmed across Ireland whereas native oysters are fished from wild stocks.

Irish name: gliomach na hIorua

Scientific Name: Nephrops norvegicus

Dublin Bay Prawns are a type of lobster found in benthic habitats throughout the North-eastern Atlantic and Mediterranean. These prawns typically dwell in muddy or sandy substrates at varying depths(10-800m), often forming burrows to protect themselves from predators and unfavourable environmental conditions. Their life cycle involves several larval stages, eventually developing into adults characterized by a distinctive, elongated body and prominent claws. The Dublin Bay Prawn is an integral component of Irish Fisheries, with the landings for 2022 valued at €82 million, making it the most valuable species landed by the Irish fleet.

Irish name: Muirín

Scientific name: Pecten maximus

King scallops are bivalve molluscs occurring along the Atlantic coast of Europe. These bivalves are typically be found in shallow depressions, buried in the surface layer of soft sediment. They are therefore primarily fished using dredges or bottom trawls. One of the more unique traits of the King Scallop is the ability to swim by rapidly opening and closing their shells, thereby generating a jet propulsion of water. Furthermore, these bivalves have a sophisticated visual system consisting of over 200 minute eyes lining their mantle. Similar to mussels, these filter feeders can also consume naturally occurring toxin producing phytoplankton and are therefore screened by the Marine Institutes Biotoxin Monitoring Programme before being placed onto the market. The Irish scallop fishery is significant, consisting of both inshore and offshore fishing areas with approximately 2200 tonnes fished in 2022 at an estimated value of 7 million euros.