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NATURE When the rats come

Outdoor Living
Nature’s ways of dealing with unwanted pests

John Shelley

IIt’s nine o’clock in the evening. The night is bright and full of moon with stars beyond, yet the light feels cold and thin. We have yet to find any real warmth in the air although we are officially into spring. Winter always drags her heels on the way out.
Mid afternoon sunshine has our sense of hope elevated; we feel that soft glow upon the cheek, off with the coat until an hour before tea, when comes that certain chill, either damp or dry according to the day, with dusk creeping slowly over the hills.
The presence of unwanted guests has the poor dog going slowly mad. They seem to be hanging out in the fuel shed, where they no doubt find my stack of firewood a safe and secure lodging. I think we have rats there. As yet we have no proof beyond reasonable doubt, but given that rats are endemic in the Irish countryside it is likely. ‘You are never more than twelve feet from a rat,’ said my neighbour, ‘There are that many of them.’
‘Where had they come from?’ I asked him, fully expecting the British to have brought them, or the Anglo-Normans, at least.
‘Rattus norvegicus,’ he told me, nodding sagely. ‘From Norway. They came with the Vikings, hidden in the bottom of their longboats.’
In Irish, the rat is ‘Francach’, meaning ‘from France’. Most probably, Francach first arrived in this country in the early 18th century on board trade ships sailing from Russia. So the poor Russians get the blame for this as well.
However they got here, it is evident that the brown rat finds the Irish climate very much to its liking. It is never too hot and seldom too cold for breeding to take place and there is almost always an abundance of food. A female rat is sexually mature and able to start her reproductive life at only three months old. She has the potential to produce as many as five litters of young in a year, with as many as ten or twelve ‘kits’ in each litter. If half her offspring were female and all survived – well, I tried to do the sums but got lost at hundreds of individuals around the third generation.
Happily (for us if not for them) rats have an extremely high mortality rate, with up to 95 per cent dying in the first year of life. Even so, that high rate of reproduction keeps the population at its optimum level.
We have unlikely allies in our war upon the rat. Last night I heard a vixen crying over the hill. The lengthening days have turned her thoughts toward family life once more, so that she calls through the dark for a suitor. She will eat meat whenever she can, and will feed her cubs on the same. Rats form an important part of the fox’s diet. If we kill the fox, we spare the rat.
The stoat is another friend. Bloodthirsty and a cold-hearted killer he may be, but what would we rather have, a shed full of rats or an occasional glimpse of little Easog hunting through gaps in the stone walls or raising his head to watch us watching him. I think he sees us as we would see a mighty fish, as potential, if very unlikely, prey. He can stay, as can the fox.
There is no doubt that mink also make great inroads into the rat population. If only they would stick to that, then we might tolerate them. They will kill whatever they can catch, whether they are hungry or not.
Now, how best to tackle the rats? Based on past experience, we fully expect to have one or more foxes passing through, to which we have no objection (as long as they leave our hens alone). There are stoats here too; poisoning their lunch is pretty much out of the question. We shall try the old sewer pipe trick that works so well for mink.
Prop five feet of six-inch pipe against a bank at an angle of sixty degrees and bait it well. (Cat food is good and smelly and will attract plenty of potential customers.) Hungry rats will clamber in and be unable to climb back out. The difficulty lies in dealing effectively with them once they are captured.
Warmer days are just ahead and with these the rats will disperse. For now we will catch them, by the pipeful.