Seals are not threatening commercial fishing stocks in Irish waters, with the possible exception of wild Atlantic salmon, according to new research led by Queen’s University Belfast (QUB).

The findings show seals are having no significant impact on populations of the most popular species of fish caught for commercial purposes along the south and west coasts of Ireland.

The research was led by QUB in collaboration with University College Cork and the Marine Institute in Co Galway. Its conclusions suggest seals do not compete with fishermen over the stocks. The issue of seals in Irish waters has been controversial in recent years and there have been calls for culls.

Lead researcher Dr Keith Farnsworth from QUB’s Institute for Global Food Security said: “We need to emphasise that this work in no way says that seals cause no problems for the fishing industry. They do create significant problems for static fishing gear used by estuarine salmon fishers, and they may also impact on numbers of wild salmon.

“What we are saying is that for most commercially fished species – herring, mackerel, cod, haddock, whiting and 30 other species – seals are having no significant negative effect on numbers.

“This is because seals are eating smaller fish than the mature specimens that fishermen are required by law to catch. So seals are often eating the same species of fish as we buy in the supermarkets, but younger versions. And there are more young fish than mature fish in any given species.

“In fact, we found evidence that seals may actually be doing the fishermen a favour, by eating some species that prey on the valuable stocks the fishermen are after.”

Prof David Reid of the Marine Institute said: “What this work shows is that the only way to resolve questions like this is to look at the detail. This work used material as diverse as the gut contents of seals and fish, through seal ‘scat’, to samples taken from commercial catches and research vessel surveys, and elaborate mathematical models.

“The idea of seals being direct competitors with fishing boats out there intuitively seems obvious. But actually, it is not really true. They both ‘eat’ fish. But not the same fish, and they do not compete with each other.

“This is not to say that seals do not compete with fishermen in other ways. In other recent work we showed that fishermen who use set nets around the coast of Ireland can lose fish straight out of their nets to seals. But as with this study we needed to go into the detail, and get our hands dirty to prove that.”

The findings of this research are based on data from an area roughly 100 miles off south and west Ireland, encompassing the coastlines of counties Waterford, Cork, Kerry, Clare and Galway. Data was collected from seal droppings of grey and common seals and collated by researchers from UCC.

Data was then interpreted by researchers at QUB and their conclusions have been published in the Journal of Applied Ecology. The study was funded by a Beaufort marine research award, with the support of MI, funded under the marine research sub-programme of the Irish National Development Plan 2007-2013.

The salmon angling season gets under way on Friday on a limited number of river and lake fisheries. Lough Gill (Sligo), Carrowmore Lake (Mayo) and the Drowes River (Donegal-Leitrim) continue their early season start and, for the fourth successive year, the lower Liffey prevails on a catch and release basis.

Howth Sea Angling Club held its annual awards night recently in the angling centre on the west pier. The two anglers to represent the club in next year’s all-Ireland master angler competitions will be Tom McAdam in the shore category and Gerry Clarke in the boat section. angling@irishtimes.com