Over the past week I have found a depressing amount of eggs which have been predated by crows. A scattering of pheasant eggs is not usually a particularly desperate sign because you have to wonder whether or not the hen bird was clever enough to build a clutch in the first place. I’ve found pheasant eggs all over the place, and many are just mindlessly dropped out in the open by birds which have an intolerably low IQ. But when you find the eggs of wild birds being stolen and cleaned out, you realise that you have a problem.
My girlfriend found the remains of a snipe’s egg in the hayfield two days ago, and it was with infinite regret that I came across 3/4 of an empty grouse egg shell while cleaning out the peat haggs this afternoon. You could even see the marks that the crow’s beak had made on the inside of the egg where it had almost punched through the whole thing as it guzzled out the yolk.
I have to assume from this that I have lost an entire clutch of grouse eggs, and while the snipe’s loss is frustrating, the grouse hurts. I can’t stand to let that happen too often, and I only have to hope that the hen will lay again. In the meantime, I have a feeling I know where I can find the culprits. GWCT work at Banchory in the 1970s and 80s showed that old crows are the most likely birds to have learnt the tricks necessary to hunt for eggs, and these are inevitably the wiliest and most cunning of all. At the same time, other research has shown that grouse numbers are only really suppressed by crow predation when the vegetation is too short and the hens can’t build the nests they need to keep safe. It is as much a question of habitat as it is a problem with predation.
I have been grubbing around catching up some of the less offensive young birds on the low ground and have neglected to keep on top of the real trouble makers. This is partly because of time restraints, but also because birds seem to be peculiarly unresponsive to my larsen traps this year. I need to set aside a couple of days and dig these specific offenders out from their murky lairs. With the weekend coming up, I’ll make time to sort this out. My greyhens are probably laying (or at least nesting) by now, and if I find that a black grouse egg has been broken into, there will be hell to pay.