A unique and rare relict from the Past!
Pollan (Coregonus autumnalis) is a freshwater species of the Whitefish Family, closely related tp the Salmonidae. They are found in Europe as a resident population in Ireland and as a migratory species in Russia on the coast of the White Sea and Arctic Oceans. It is a fish unique in Western Europe, being a landlocked glacial relict from the last ice age. Its stronghold is in Lough Neagh and it also occurs in Lower Lough Erne, in Lough Ree and Lough Derg (forming only 1% of total fish biomass). Recently Pollan have been confirmed from Lough Allen by researchers from NUI Galway and work done by Central Fisheries Board, Dublin and Agri-food and Biosciences Institute, Fisheries and Aquatic Ecosystems Branch, Belfast (2007). Numbers are believed to be low. Pollan were also reported to have occurred in other small lakes in the North West of Ireland ó but not in recent times. It occurs in the Arctic around Alaska, N. Canada and Siberia. A landlocked population similar to that in Lough Neagh and Lough Allen also occurs in Lake Baikal.
The picture above is of the anadromus Arctic variety but it is the same species. Any good pictures of Irish specimens would be much appreciated. For this one, much admiration and appreciation to the Siberian Department of the Russian Academy of Sciences for a great image and much interesting information (in Russian)
The Pollan is a freshwater Corygonid fish with a unique Irish distribution not being found elsewhere in Western Europe. From a conservation viewpoint, it is one of the most important components of Irish biodiversity. Pollan is a freshwater whitefish that is known to occur in five Irish lakes, Lough Neagh, Lower Lough Erne, Lough Ree, Lough Derg and Lough Allen. The Lough Allen population has only been confirmed in 2007.
Action Plan for Pollan.
- The population in Lough Neagh is now widely believed to be the last viable population in Ireland, and still supoports a small scale commercial fishery. The endemic status of the fish and its dwindling populations have given it a high importance for conservation. Consequently, a species action plan for Pollan has been drawn up. This consists of four major objectives.
- Maintain the existing Pollan stocks and prevent further decline in any of the populations.
- Create back-up stocks of all four of the pollan sub-populations by 2010.
- Restore the Lower Lough Erne and Shannon lakes populations to demonstrably sustainable levels by 2015.
- Restore Pollan to sites where they have become extinct (such as Upper Lough Erne) by 2015
One potential approach for conservation is to develop culture techniques for the fish in order to produce fry or fingerlings for restocking waters. In 2005 Potential broodstock were captured from Lough Neagh for breeding purposes.
The threats to Pollan come mainly from competition, habitat loss, and eutrophication. Roach, which is a non-native species, was introduced for the coarse fishing industry and is the main competitor for Pollan. Zebra Mussel infestation, which contaminates potential Pollan spawning sites, is another major threat. Possible change in summer temperature due to global warming could inhibit spawning of Pollan, which need summer water temperature of not above 22 degrees C.
Pollan is a regulated commercial species in Northern Ireland, and is subject to a closed season in the Republic. It is listed on AnnexV of the EU Habitats Directives (92/43/EEC) and is listed in the Irish Red Data Book as 'Endangered'.
It would be great to see more research on the status of Lough Allen Pollan. Angling Clubs and fishermen in general maybe could report any specimens caught or seen. And the spread of Zebra mussels any further up the Shannon system should be avoided at all cost. Are they spreading into Lough Allen through boat traffic?