Eventually, it gave up and flew off. I think it had misplaced the nut, so that its bill was striking the hardest and most intractable part of the shell. On investigation, I found a sign of previous activity further up the crack: another hazelnut, this time successfully dealt with - the kernel had been removed through a large hole in the shell.
Nuthatches are found throughout Wales and the southern half generally of the UK, and are here all the year round. They are impressive little birds, with their long thin beaks, blue-grey upper parts and buff-orange underside. For me, though, the best bit about the nuthatch’s plumage is the black bandit eye stripe that follows the line of its bill right across the side of the head. Male and female look alike.
It is a bird of woodlands and large gardens, where it feeds on insects and other small invertebrates as well as on nuts and seeds. It comes readily to bird tables, where it often lives up to its bandit eye stripe by being a bit of a bully. Having said that, the ones I’ve seen in my present garden seem fairly shy. In winter it flocks with tits and other small birds, tending to move around together - in flocks birds help each other find food, and have better protection against predators. The nuthatch likes large mature trees, and can move up and down the trunk with equal facility (the tree creeper, in contrast, can only move up). It has a loud and strident call.
Nuthatches nest in holes in trees, the entrance to which they make smaller (and therefore safer) by adding mud to partly close it up. They will also use nest boxes. A pair will raise maybe six or more young, lining the bottom of the nest hole with bark and dry leaves. For a short time this summer, our garden was thrillingly filled with nuthatches, as a local brood somewhere in the wood behind us fledged.
There is only one species of nuthatch in this country, but others are found elsewhere in the northern hemisphere, especially in Asia, but also the USA and Canada, and some parts of north Africa as well as across Europe. All have a similar style of plumage, including in most cases the eye stripe, and all share the same habit of nesting in holes and crevices, though one or two species will excavate their own nest holes. Some nuthatches are not woodland birds, for example the rock nuthatches which I enjoyed watching a few years ago on a visit to the Greek island of Lesbos. They are lovely birds, and for me it’s always a thrill to see them.