This follows EU Mulkear Life project confirming “dramatic results” in relation to a device it has deployed along the river designed to deliver sea lamprey to its spawning grounds.
Ruairí Ó Conchúir, the MulkearLife project manager, said the fish pass has proven to be a “groundbreaking success and we would hope it would lead to the stabilisation and enhancement of sea lamprey population across Ireland”.
The sea lamprey is protected under the EU Habitats Directive and according to Mr Ó Conchúir, its population across Europe has declined by 50% in the past 15 to 20 years.
The building of barriers, including weirs, and the loss of suitable habitat to spawn are the primary reasons for their decline on the Shannon system.
Now, personnel from the €1.75 million project have deployed fish passes produced by Ennis-based firm Enform Plastics at two locations along the Mulkear River, including Annacotty Weir.
Mr O’Conchúir said the results can be replicated on rivers across the country.
Inland Fisheries Ireland chief executive Dr Ciaran Byrne said yesterday that the development of the design is a major development for IFI, stating that it is “significant in terms of sea lamprey conservation in an Irish context”.
Mr Ó Conchúir described the pass being like “an egg box”. He said the plastic sheets contain a large number of knobs reducing the velocity of water to make it easier for the sea lamprey to ascend the weir.
Project officer with MulkearLife, Glen Wightman, said: “The results have been amazing and extremely encouraging.”
During one monitoring session, a minimum of 27 fish ascended the weir using the new substrate while no fish were successful elsewhere on the face of the weir.
The project has ordered 200 of the fish passes.
Mr Ó Conchúir said the lamprey getting through the weir opens up an additional 184km of spawning habitats along the Mulkear river.
He said: “We have proven that this fish pass works and we believe that it will work for salmon, though we have to carry out tests first and that will be later in the year.”
“This is a first for Ireland. It is the first ever instance where a fish pass has been specifically designed to help the sea lamprey passage.
“This is a local solution developed to stabilise sea lamprey population on the Lower River Shannon Special Area of Conservation (SAC).”