Wednesday July 15, 2026
Oceanographic —
A new report confirms that over one-third of wild Atlantic salmon populations in Ireland now carry genetic material from escaped farmed fish, raising urgent concerns over the long-term survival of the iconic species.
The landmark study, commissioned by the Marine Institute and led by University College Cork (UCC) alongside Inland Fisheries Ireland (IFI) and Teagasc, is the most comprehensive genetic assessment ever conducted in the country. Scientists mapped out the DNA of 6,322 juvenile salmon from 133 rivers between 2023 and 2025, contrasting the data with 1,755 historical baseline samples from 2003 to 2008.
While 66% of wild populations showed zero signs of genetic mixing, the remaining 34% displayed varying levels of farmed fish introgression – the transfer of genetic material from one species into the gene pool of another divergent species. The impact was categorised as low in 27% of rivers and moderate in 6%, while a critical 0.8% of populations exhibited severe genetic alteration.