Genetic testing by a University of Salford researcher has debunked the assumption that pike were introduced to Ireland by humans, and has shown that the predatory fish may have arrived naturally on the island up to 8,000 years ago.
Computer modelling of genetic data has indicated that pike probably colonised Ireland in two waves; the first occurred approximately 8,000 years ago, close to the end of the Ice Age, and the second occurred approximately 1,000 years ago, with the Normans. This is the first time evidence has been found for natural colonisation of a strictly freshwater fish to the island of Ireland.
Pike are found across the northern hemisphere and can grow up to 1.5m in length. They are a voracious ambush predator and will eat fish, mammals and birds. They are also highly prized by anglers and were eaten by people as far back as Roman times. In modern times, pike are more usually returned to the water by fishermen.
Salford’s Professor Stefano Mariani worked on the project with colleagues from University College Dublin. The study was funded by Inland Fisheries Ireland and the Irish Federation of Pike Angling Clubs.
Professor Mariani, from the School of Environment & Life Sciences said: “We should always question long-held assumptions, and examine the best available evidence. At this point, it would be irresponsible to ignore these strong patterns of pike diversity, but we are also keen to investigate this further and provide a more exhaustive picture.”
The full report can be read here (PDF).