Vigilance urged as quagga mussel discovered for first time in NI

The discovery of an invasive species of mussel for the first time in Northern Ireland will add further pressure to the “beleaguered” freshwater system, Environment Minister Andrew Muir has said.

The first confirmed case of the quagga mussel has been reported in Lower Lough Erne in Co Fermanagh.

Quagga mussels originate from Eastern Europe and can threaten native animals and plants.

They can also block water pipes, which can cause flooding and infect water supplies.

Officials are now identifying other waterways in the region to be checked for the presence of the species.

Scientists from the Agri-Food and Biosciences Institute (AFBI) collected samples that were confirmed following DNA analysis at Queen’s University Belfast.

The Department of Agriculture, Environment and Rural Affairs (Daera) said the quagga mussel is a small bivalve mollusc similar to the invasive non-native zebra mussel.

The species has spread rapidly from its native region in Ukraine during the last few decades through Western Europe and to North America and Mexico.

It was first recorded in Britain in 2014 and in Loughs Ree and Derg in Ireland and in the main River Shannon system in 2021.

The department said quagga occupy a wider range of depths than zebra mussels and will eventually outcompete and displace them.

They can spread through recreational boating, angling traffic, trailered craft travelling overland and the transfer of equipment such as paddle boards or canoes.

Mr Muir said: “This confirmation that the highly invasive quagga mussel has arrived in Northern Ireland represents another significant pressure to our already beleaguered freshwater system.

“Increased vigilance and surveillance is critical.

“My officials are engaging with stakeholders and public agencies to alert them to this arrival and the need for enhanced biosecurity measures.

“Cross-border engagement also continues through the Shared Island Biosecurity and Invasive Species Initiative.”

Rose Muir from the Northern Ireland Environment Agency (NIEA) invasive non-native species team said: “There is no effective control or eradication method for quagga mussel once it has established in a water body.

“The best method of slowing the spread and reducing the risk to other water bodies is by applying better biosecurity through the Check, Clean, Dry approach.

“We are urging all water users to follow this protocol strictly when moving between water bodies.”

Dr Kevin Gallagher, senior scientific officer at the AFBI, said: “The confirmation of quagga mussel in Lower Lough Erne is significant given the connectivity of major water bodies.

“Once established, this species can spread rapidly and cause substantial ecological and economic impacts, including altered food webs and infrastructure fouling.

“This underlines the need for enhanced surveillance across connected systems, including Lough Neagh, and strict biosecurity to limit further spread.”

Daera said the arrival of the quagga most likely came from a connected invasion along the Shannon–Erne corridor.

A statement said: “It is therefore plausible that quagga are already present but undetected in intermediate waterbodies, including Upper Lough Erne.”

Officials are planning to identify those waters that should also be sampled by assessing the potential pathways for the spread of quagga mussels into other water bodies.