Pacific salmon are turning up in Irish rivers, it has been revealed.
Some of the country’s most prestigious angling spots have recorded the non-native pink or humpback species, which originates on the west coasts of the US and Canada and Russian Arctic regions.
In the past two weeks, reports have come in of the invasive fish on the Foxford and Coolcronan fisheries on the River Moy in Mayo, the Galway Fishery on the River Corrib, the River Cong and the Drowes Fishery on the Donegal-Leitrim border.
Inland Fisheries Ireland (IFI) said the appearance of the species is a concern because of the impact it could have on Ireland’s Atlantic salmon.
A similar issue has been reported on some fisheries in Scotland and there is no definitive explanation.
It has been suggested that some of the Pacific species have made their way south after “straying” from rivers in northern Norway or Russia. They were introduced to some Russian fisheries in the 1960s and have colonised west along Arctic coasts.
Dr Greg Forde, IFI head of operations, described the arrival as a mystery but ruled out salmon swimming to Ireland from the eastern Pacific.
“It seems unlikely that these fish made a migration due to their small size,” he said. “The concern is that when angling, anglers are only exploiting about 15% of the salmon stock so there are likely to be several more of these fish in rivers.”
Shane Gallagher, manager of the Drowes fishery, said an angler on his river reported catching a pink salmon of about 5lb in weight.
“They are a complete unknown quantity,” he said.
“They are non-native because they have never turned up before. We don’t know what impact this could have on our own native fish.”
Fisheries chiefs have urged anglers who catch any of the pink salmon or members of the public who see them to record the date and location of capture, length and weight of the fish and to take a photograph of the fish.
They also want the fish kept so they can run further tests to determine maturity stage and genetic origin.
The ones caught in Ireland to date are small
Pink or humpback salmon are a migratory and native to river systems in the northern Pacific Ocean and parts of the Bering Sea and Arctic Ocean.
They have also established themselves in northern Norway and in the far northwest of Russia, with some populations believed to have originated from stocking programmes in Russia in the second half of the 20th century.
The fish have some distinguishing features including large black oval spots on the tail, very small scales much smaller than Atlantic salmon, an upper jaw which extends past the eye. They also have 11-19 rays on the anal fin and no dark spots on the gill cover.