Dominic Couzens On - Hawfinch

With bumper numbers of this awe-inspiring bird flocking to our shores over the winter period, your chances of seeing one increase

You can imagine the scene. A Hawfinch perches upright in a tall forest tree, looking out over the canopy, well out of sight of any human being. As with every bird, everywhere, it is hungry, and here among the twigs and branches of its favourite woodland giant, it knows there is plenty of food.

After a brief glance down, it manoeuvres its massive bill, opens the mandibles and plucks what it needs – a juicy caterpillar. Hang on, is that a mistake? A Hawfinch is eating a caterpillar? Is this the same Hawfinch that is famous for little more than having an outsize bill, capable of exerting enough force to crack a cherry kernel, or even an olive stone? Yes, this is the same species, alright. But this is the surprising Hawfinch, the real bird, which has a quiet lifestyle that very few people know about.

In the summer, oddly, it almost entirely forsakes its winter diet of nuts and fruits and feeds instead on soft-bodied invertebrates. The famous bill, its prized asset, is rendered less useful than usual and might even be a hindrance at such a time. But in the summer forest canopy, insects roll off the trees and times are easy, so the specialist becomes a temporary member of the ranks of ordinary insectivores, competing with Blue Tits and flycatchers.

Young Hawfinches, in their first few weeks of life, must wonder what their bill is actually for. Of course, the Hawfinch’s mandibles do come into their own in the depths of autumn and winter, when seeds are everywhere. With so many species competing for the nutrition they bring, it pays to have an advantage, and the Hawfinch bill is simply more powerful than that of any other finch, allowing it access to larger and harder seeds and stones. And while the sheer size of the bill is what every birdwatcher can see, easily, it is the internal structure that is the marvel.