Unprecedented widespread occurrence of Pink Salmon Oncorhynchus gorbuscha in Ireland in 2017.

The occurrence of non-native pink salmon Oncorhynchus gorbuscha in multiple river systems in Ireland in 2017 was unprecedented and reflected similar concurrent events observed in other countries in the North Atlantic region. Thirty-six fish were captured in a total of 11 river systems located in the south-west, west and north-west of Ireland in the period June to September 2017. The biological characteristics of sampled specimens are described and the potential for establishment in Ireland are considered.