I WAS in Lanesborough in Co Longford the other day and, as I walked across the bridge that connects it to Ballyleague in Co Roscommon, I stopped and looked over the parapet.
Below me was a concrete channel which runs beside the river, and eventually joins up with it. This is the ‘Hot Water Stretch’, internationally famous as one of the top coarse fishing spots in Ireland.
But that day there wasn’t a single person fishing. A glance at the ESB power station beside it explained why. No steam was coming out of the chimney stacks. The power station was not operating. It hasn’t operated for several months due to some technical problems.
When it is generating power it sucks water from the River Shannon, boils it, using milled peat from the surrounding bogs as fuel, and pipes the resulting steam through turbines to produce electricity. After the steam has done its job some of it escapes into the atmosphere through the chimney stacks, but some of it is re-condensed and fed back into the river. So the power station emits a steady stream of warm water into the Shannon along the channel anglers know as the Hot Water Stretch.
Lanesborough is at the upstream end of Lough Ree which is the third largest lake in the Republic and full of fish. These fish, especially large coarse fish such as tench and bream, are attracted to the warm water, particularly in the early months of the year, and congregate in the Hot Water Stretch in large shoals, which is what attracts the anglers.
But why are tench and bream attracted to unnaturally warm water? The answer is almost certainly that they are not native fish. They belong naturally to countries to the south and east of us where water temperatures are normally higher, particularly in spring and early summer.
They were imported by fish farmers in the Middle Ages and these fish farmers were almost certainly monks or nuns. Fish farming is a very ancient practice. We know the Chinese were raising carp in ponds, largely to eat but also for ornamental purposes, nearly 5000 years ago. The ancient Egyptians were skilled at farming fish and in the first century AD a man called Lucius Modestus Columnella wrote a detailed treatise on Roman pisciculture. But there’s no evidence for true fish farming in these islands before the Normans invaded Britain in 1066. Norman chronicles, including the Domesday Book, make it clear that they farmed freshwater and salt-water fish in an extensive and quite sophisticated way. But it is possible that fish farming arrived in Ireland before the Normans appeared here in 1169.
The great continental monastic orders were also skilful and enthusiastic fish farmers and some of them had set up abbeys and convents in Ireland before the Norman invasion. One of the reasons for their enthusiasm was the extraordinarily large number of days in the year when they were forbidden to eat meat. In modern Ireland, tench and bream are not regarded as being good fish to eat. But this wasn’t always the case and part of it may come down to the fact that we’ve forgotten the techniques for cooking them properly. The great advantage of these two species is that they are relatively easy to keep in ponds at high densities as they don’t need the levels of dissolved oxygen in the water that other species demand.
So when the hot water returns to Lanesborough the anglers should give thanks to the medieval Church.
© Irish Examiner Ltd. All rights reserved