Minister puts spotlight on pike threat to pearl mussel

Lough Corrib...threat.

The presence of pike on the water systems in North Connemara may be indirectly damaging an endangered species, freshwater pearl mussel, a Government Minister has said.

Heather Humphreys, who is responsible for Arts, Heritage, Regional, Rural and Gaeltacht Affairs, has confirmed that the release of pike in some lakes upstream of Lough Corrib may be negatively impacting on freshwater pearl mussel.

Minister Humphreys said it was regrettable that pike fish were released into the Owenriff system recently, and she said the “Inland Fisheries Ireland are working to control or ideally eradicate these introduced fish”.

She said that pike are not normally associated with the fast-flowing stream conditions that are typical of the Owenriff River and are not usually a factor in pearl mussel conservation.

However, Minister Humphreys, speaking in Dáil Éireann, said pearl mussels depend for some time of their lives on juvenile trout or salmon.

“The larval mussels attach themselves in a parasitic manner to the gills of the small fish and then drop off to begin life on the river bed. There is a possibility therefore that pike could have an impact on the number of juvenile fish available to the mussels.

“It is believed however that the juvenile fish that host the mussels are likely to have spawned close to the mussel beds, and it may be the case that such stream-living fish are not impacted by pike elsewhere in the river system,” the Minister said.

She said her department intends to carry out a “fish host survey”, in 2017, “including the Owenriff, to sample juvenile salmon and trout for mussel larvae and will review available fish data to assess trends in host fish populations.”

There is disagreement between those who fish for salmon or trout on the western lakes which are designated wild trout fisheries and those who fish for pike. By the end of the year a new policy will be implemented on the management of pike in the seven lakes and rivers where their numbers are currently controlled but there both sides are diametrically opposed on what that policy should be.

See full story in this week’s Connacht Tribune.