I've seen loadsa pheasants in my time; but never in all my born days have I seen a pine marten Martes martes. Although several of my naturalist neighbours have. On Sunday morning we were pottering about and a pine marten lolloped through the gate to the haggard and started exploring the yard as we watched from the kitchen window. It was amazin' mystic, wonderful to see this top predator making our home their own. What's that got to do with the native squirrel? You may well ask. Because they are both making a come back in the Irish Midlands and there is some evidence that forward march together is not coincidental. Grey squirrels Sciurus carolinensis were introduced from North America to Ireland in 1911. They are bigger and bolder than their red cousins and have spent the last 100 years displacing the reds from their habitat.
Another study from NUI Galway [PDF of original survey results] looked at the relative distribution of greys, reds and martens in 2007, 2012 and 2019. A lot of that data was crowd-sourced after an extensive publicity campaign so that may cast some asparagus on the absolute numbers of reports [3,402 in 2019 up 20% from 2012] but there are significant differences in the proportions among the three species between the two survey years. On the face of it it looks like reds have gained ground in the Irish Midlands with a little help from the depredations of a resurgent marten population.Wild Wood book. Which is fair enough in a memoir. It's a pity I didn't get to referee either of these papers because, I would have devoted a day of my time to constructively picking apart the methodology and assumptions. With any effort at all I'll say a) If the hypothesis is that it is a specific pheromonal response to scent of martens, I would have used cat urine as a control rather than nothing at all. b) In the 3rd paragraph of the results of the NUIG survey a number of 3 [species] x 2 [years] contingency tables have been analysed with ChiSq. They have looked up the resulting numbers as if there are 3 degrees of freedom. But that's almost certainly not true. There are only 2 d.f. because once you've assigned numbers to #grey and #red then #marten is not 'free' to vary: it must be 1 - (#grey + #red). That's sort of okay, because using the wrong line of the table results in a more conservative test of the difference. Then again, if they can't do elementary stats correctly, critical readers are justified in giving side-eye to the rest of the study.
But here's an interesting anecdatum. Last year we had a plague of rabbits, really for the first time in 25 years. I constructed an
elaborate [2x1s and chicken-wire] rabbit proof fence for the two ends of the poly-tunnel so that the rabbits were at least slowed in their depredations on the beans, lettuce and tomatoes. This year looked like being the same. A couple [pair, M+F, breed-like...] of rabbits were to be seen daily in the garden nibbling away at the greenery bold as brass. I would ineffectually peg small logs and large stones at them but I was girding my expectations for no cabbage in 2021. And then from about 3 weeks ago the rabbits weren't there any more and two weeks later a pine marten graces us with their appearance. Like Darwin's ruminations on the relative count of clover, bees, cats and mice; this is another example of my enemy's enemy is my friend.
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