If you hear a really persistent repetitive whistle, and I mean annoyingly repetitive, then it's likely you've got a Nuthatch in the neighbourhood and he's getting stroppy about a cat, a roosting owl, a Sparrowhawk or even just a squirrel. Nuthatches are capable of finding offence anywhere and they love mobbing anything vaguely predator-ish.
They seem to be coming to the peanut holder more and more, and with their fearsome dagger-like bills and vigorous demeanor, they tend to dominate most other birds. They’re often illustrated in bird books on the next page to the Treecreeper and, quite correctly the Nuthatch is usually shown descending a tree unlike my watercolour here where I sketched him perched on my bird feeder, whereas the mousy Treecreeper tends to ascend the trunk.
Nuthatches wedge nuts into bark crevices and then hack them apart with a series of ferocious blows. If you here an erratic tapping sound when you’re in a wood it’s worth investigating as you’ll often catch a glimpse of a Nuthatch preparing lunch. They usually stay beneath the tree canopy but a few weeks ago, while I was painting live up at Stowe National Trust Gardens, I got some good sketches of one in bright sunlight. He was mobbing a squirrel from the topmost tip of a spruce tree.
The Nuthatch’s nest is one of the great wonders of evolutionary biology. They always choose a tree hole and then reduce the size of the entrance hole with mud to keep predators out, a practice also known with tropical Hornbills. I once found a nest hole in a massive felled oak trunk so was able to get a good close look and was hugely impressed by the workmanship of the little plasterer. Although the hole had been precisely reduced to a perfect circle, the hardened mud surface itself was intricately stippled and textured, presumably so it wouldn’t stand out against the surrounding rough bark and draw the attention of predators.
Nuthatches are thriving all over Europe and they are extending their range northwards quite rapidly. They are also laying their eggs several days earlier than they did in the sixties and they are raising larger families, so this is one species at least that seems to be adapting well to a changing climate.
First published in Four Shires Magazine