Could the humble pollan fish from Lough Neagh be key to climate change research? Alastair Fenn explains.
Around world there is an exclusive list of rare and most sought after foods that include meats, spices, fungi, fish eggs, melons, chocolate, saliva, yes, you heard me right, saliva, and even precious metals.
If you live around the shores of Lough Neagh your staple diet probably consisted of the famous Lough Neagh eel but a trip to a local chip shop located in Toome will allow you to order another species of fish that has graced our local pallets and is one that has survived the last ice age; the Lough Neagh Pollan.
It is a species that is so important scientists believe it could help unlock the secrets of our continued global battle with climate change.
The fish is a glacial relict of an Alaskan-Siberian whitefish species and is not found anywhere in Western Europe outside of Ireland. Although they are found in 4 other locations in Ireland they are known to be extinct or in serious decline in those areas. The only remaining abundant population of Pollan is in Lough Neagh.
14,000 years ago the species entered the Shannon system as a migratory fish from the sea where it spread to the Lough Erne and Neagh systems. As the sea temperature and salinity increased, Pollan lost its migratory habit and became restricted to freshwater.
The current threats to this globally important population are funny enough climate change itself but also the induction of Invasive Alien Species such the Zebra mussel and the continued eutrophication of the water body itself.
The conservation value of this species is not only important for the commercial fisheries that rely upon weighty landings to generate income but for examination of future climate change scientists who believe that advances in DNA based analyses may show important genetic differences between Irish stocks and provide evidence of genetic divergence since the last glaciation.
In the future other nations in addition to Ireland and the UK may have an interest in analysing global relationships as a means of gaining an insight into former sea and ice conditions.
With results being inputted into future climate change models.