Understanding Irish Brown Trout

A high level of genetic diversity in brown trout populations. Pic: IrishFlyFisher.ie

A three year research study between Inland Fisheries Ireland (IFI) and Queen’s University Belfast was presented at this week’s ‘Understanding Brown Trout — Genes, Ecology and Citizen Science’ one day conference.

The research study looked into the genetic make-up of Ireland’s brown trout and sea trout populations and will provide Inland Fisheries Ireland with valuable information on how genetic diversity is distributed among trout populations within certain catchments.

The main areas in the study included selected Dublin rivers, the Moy catchment area, Co. Mayo, the Shannon system (Lough Derg, Lough Ree and Lough Sheelin), in addition to Lough Corrib and Lough Ramor.

Among the key findings presented were:

1. There is a high level of genetic diversity in brown trout populations evident from all catchments studied. For example, there are 27 genetic groupings of brown trout populations in the Moy catchment, 17 in the Liffey, and 34 in the Lough Ree, catchment, while there are 40 in the Lough Derg catchment;
2. Western tributaries keep Lough Conn well stocked with brown trout, in particular the River Addergoole complex and River Deel system (together they contribute 77% to adult stocks of the lake);
3. Key contributors of brown trout to Lough Ree are the River Inny and the Camlin River (over 80%);
4. Barriers and poor water quality were found to be significant factors in unravelling genetic diversity patterns.

Importance of tributaries to Lough Conn’s fishing cannot be over-estimated. Pic: FishinginIreland.info

The project also highlighted how successful ‘citizen science’ can be with IFI, QUB and angling clubs working together and with angling communities from across all three main project areas critical to the success of the project.

Dr. Cathal Gallagher, Director of Research and Development at Inland Fisheries Ireland commented that the conference was, “a huge success and the findings of the three year study will be of interest to anglers, conservationists, fishery managers and the wider public. More crucially, it has been an exciting and exhaustive project that will have real practical applications and will assist Inland Fisheries Ireland in making the correct and most cost effective fisheries management and conservation decisions.”

Click here for more information from Inland Fisheries Ireland.