Acorn Eaters

Oak Tree in Cherry Tree Wood

Dear Readers, I have already mentioned that this year is a mast year for acorns, but you couldn’t really miss it if you’ve been out in the woods of North London in the past few weeks. We are positively crunching through the acorns, and it has not gone unnoticed by the animals that feed on them. Certainly the grey squirrels are in for a nice feed during the winter, but you might have also seen one of our most spectacular birds, the Eurasian Jay.

Eurasian jay in the garden

These birds have a very distinctive, bounding flight, and the white flash above their tails also gives them away as they disappear through the trees. They are also not the most musical of birds (ahem) as you can tell from this recording by Arjun Dutta. I bet most people in the UK have heard this, but it’s sometimes hard to work out what the hell is making all the racket. It’s no surprise that in Wales the bird is known as ‘the shrieker of the woods’.

Overall, the abundance of food this year is likely to mean that more jay fledglings survive the coming winter, with a knock-on effect on the creatures that jays eat – they are omnivorous but have a particular taste for the invertebrates that live on oak trees and feed on acorns, which will also be superabundant next year. These invertebrates will feed not just jays, but lots of other woodland birds as well. Jays sometimes rob nests and kill young birds – I well remember one hammering its beak into a fledgling starling on the shed roof opposite a few years ago – but come next winter there are likely to be far fewer acorns about, and so the numbers of jays will probably fall again. The relationship between the different levels of the food pyramid is constantly changing and rebalancing.

A most excellent photo of a jay making off with a peanut.

Whenever I’ve put out peanuts, I’ve had visits from jays, but they don’t seem interested in anything else. How do they know that I’ve put the peanuts out? Are they watching, like something from Hitchcock’s ‘The Birds?’ I think we underestimate the patience of birds, and their ability to discern what we’re up to with the most minimal of cues. Fortunately, this year the jays will be fine without any intervention from me, so I can make sure that the little birds have a bit of extra sustenance without having to buy peanuts as well, which no one else seems interested in.

Seeing all the acorns on the ground in our local North London woodlands also reminds me of a magical visit to the New Forest many years ago. We were sitting outside our tent when we suddenly heard a grunting, squealing noise. A spotted sow and no less than twelve tiny piglets scurried through the camp, poking their noses through the leaf litter and munching on the acorns. The owners of the pig were exercising their right of pannage, which goes back to the Middle Ages and allows ‘commoners’ to turn out their animals to feed in the forest. As we watched, the owner wandered over, whistled to the mother pig, and the whole family started to follow him – the pigs and piglets go back to their sties overnight, to keep warm and to avoid being run over by one of the more careless drivers who race through the roads of the New Forest. Pigs seem to be immune to the effects of eating too many acorns – green acorns have a very high tannin content, and ponies are sometimes poisoned following a storm which blows down the unripe acorns. How wonderful to see pigs roaming free and doing their part to keep the forest fertile and biodiverse – their rooting around loosens up the soil, and their dung fertilises it. Plus, we should probably remember that ‘the gardener’s friend’, the robin, was likely to have been following wild boar around long before we came on the scene on our forks and spades.