As we recently mentioned, it’s a fabulous year for berries and wildlife is taking advantage. Rats, it seems, are climbing onto hawthorn trees and feasting on a rich crop of wine-red haws, which are now fully ripe, writes Donal Hickey.
Some people have been surprised to see rats moving like monkeys along the branches of trees.
Rats, however, are highly agile and at home on trees. They can also walk effortlessly along powerlines, across roofs, and up walls.
They are opportunistic feeders and have a varied diet depending on what’s available at a given time. Seeds, nuts, fruits, small birds and their eggs, snails, even young rabbits and mice — not to mention food waste left around by humans — can all be on the menu.
Rats can climb up birdfeeder poles in search of easy pickings and I know people who have stopped using such feeders because they felt they were just drawing rats.
Farms also attract rats which can eat silage, root crops, grain, and other food for farm
animals, and there’s always plenty of water to drink. A vegetable grower once told me rats even go after potatoes in drills.
For many people, the brown rat, which has been in Ireland since the early 1700s, is enemy number in the animal world.
However, they have their uses in nature. They have predators such as birds of prey and foxes and are, for instance, a big part of the diet of one of our red-listed threatened species, the barn owl.
However, a barn owl eating a rat these days is taking a big chance, studies of owl carcasses show. Research by Birdwatch Ireland and UCC found over 85% had traces of well-known rodent poisons in their systems before they died.
The widespread use of poisons is clearly having a disastrous effect on the barn owl population.
The average level of toxic exposure here is be four times greater than that observed in similar studies on UK barn owls.
Barn owls feed almost exclusively on small mammals, making them susceptible to consuming contaminated rodents.
Feeding on rats and mice, the barn owl is highly vulnerable to this type of secondary poisoning, which is believed to be largely responsible for a 50% drop in its population.
On a positive note, the southwest is still a fairly good region for the barn owl due, it is thought, to the presence of small, poison-free mammals such as voles, shrews, and field mice on which it also preys.
Rats, meanwhile, do not hibernate, but, like ourselves, like a bit of heat in winter-time and are appreciative of kind people who allow them into their homes.
As well as domestic comforts, warm homes provide ideal conditions for a raising a rodent family.
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