Making room for red squirrels
Last week, a reader contemplated a "non-aggression pact" between pine martens and native red squirrels in the martens' perceived hunting campaign against the more prolific greys.
Who knows? In the Letters to the Editor page, Damien Boyd of Cork wondered was Mother Nature correcting herself for the introduction of the more aggressive and expansive Americans in the last century. Is it time for a check on their antics?
The bigger greys are more vulnerable to predation, spending longer periods on the ground foraging than the reds and, ergo, easier for the elusive and swift-moving martens to stalk. Then, there is also a suggestion that greys are reacting to a particular predator they did not evolve with and this could result in stress-related breeding setback - or just getting out of town when those darn critter martens come riding in with open claws at the ready!
Whatever the reason, the fall in grey numbers by kills and/or territorial migration has given the reds an opportunity to recover. And they are taking it, by all accounts.
Yeats had a soft spot for squirrels. Who can resist the traditional image of the autumnal-shaded creature seated nibbling at a nut?
"Come play with me", the poet pleaded to the Squirrel at Kyle-Na-No. "Why should you run through the shaking tree/As though I had a gun/ To shoot you dead?"
A red or a grey? The verse is from the Wild Swans at Coole, published in 1919.
Lady Granard introduced the greys to Castle Forbes, Co Longford in 1911, from England. Frank O'Connor was pictured patting the head of a furry fellow at some writers' conference in America in the 1950s. This was a Carolina grey - though in the US and Canada, black-furred animals also abound. Not to be outdone, I was once photographed having a one-way conversation with a curious grey in Harvard Yard.
But let us not get carried away by images of cuddly squirrels. Those greys carry a transmittable disease called parapoxvirus, which can kill the Irish reds, but does not affect the carriers.
Since Lady Granard's gamekeeper opened her basket of new pets, the greys have spread far and wide to about 20 counties. They have followed natural food trails, nut-seeking, bark-stripping, bird-nest thieving and, having gobbled the hazels, beech mast and pine cones, scoff green acorns which the reds cannot digest.
Greys will forage in vegetable gardens, eat flowers, orchard fruits and perform acrobatics at bird tables for seeds. They will nibble saplings for sugars and sample a turnip or two. Meanwhile, the poor easily bullied reds usually remain within broad-leafed cover.
Pine martens, once trapped, shot and poisoned by gamekeepers, are now spreading back to their historic habitats. Their return is making room for the red squirrel to rebound. Reds became extinct at least twice in Ireland: they were once so plentiful that their pelts were exported.
Woodland clearances in the 18th century saw a dramatic decline and new blood was introduced from England.
Pine martens appear to be their rescuers from being overwhelmed by the greys - for now. But for how long? Nature has its own checks and balances which can evolve unexpectedly.