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Pollan Description Unmarked silvery body with an adipose fin (typical of the salmon family). Very similar to other white fishes such as Vendace, Schelly and Powan, which occur in Britain. Pollan are found in no other European country but Ireland and are a species listed for protection under the new EU Habitat Directive. Size:-
Up to 1.2kg in Lough Neagh, 170g (10oz) is more usual size. Pollan in Ireland
Pollan have become much scarcer in Lough Derg, and Noel Roycroft, former ESB and Inland Fisheries Trust, remembers when they were a common bycatch only about 30 years, in the eel weir at Killaloe, at the outflow of Lough Derg. Such have been the changes along the River Shannon, and also Lough Erne that this fish is now very much endangered in the Irish Republic. The perceived threats are the usual suspects, namely, water enrichment and introduction of non-native fish species (particularly roach). Rosell concluded that the decline in the pollan stock is probably more directly related to the introduced roach than eutrophication, as Lough Neagh is more eutrophic than Lough Erne and that although Upper Lough Erne is cleaner that Lower Lough Erne pollan are now absent. To add more petrol to the fire, recent invader to Ireland, the Zebra mussel Dreissina polymorpha Sexton, may prove fatal to the now residual populations in both the Shannon and the Erne. Distribution
outside of Ireland Xtra
Info
 Copyright
2003. ICCG ©2003 |
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The
pollan is one a handful of freshwater fishes native to Ireland. Their
limited distribution suggests that they may have been the first fish
species to colonise freshwater in Ireland at the end of the last Ice-Age
(~10,000 years ago). As the ice covering the country melted, the pressure
from the weight of this ice lessened and the land rose. The sea become
warmer and more saline and these whitefish became isolated in a few
lakes. Today Pollan are restricted to two lakes on the Shannon, Lough
Ree and Lough Derg. They also occur in Lower Lough Erne. There are records
of their occurrence in Upper Lough Erne in the past, although now their
status is uncertain. Lough Neagh, the largest lake in Britain and Ireland,
holds the healthiest population of pollan in Ireland. In the past there
was a thriving fishery where the fish were sold locally and exported
as food and fish bait. Eel fishermen still continue the tradition of
baiting their hooks with juveniles pollan. However even here the population
seems to have undergone a decline (pers. comm.). 