Greenfinch eat cones

16.06.2001

Ó Michael Woods

A regular crunching sound came from the top of my tall Corsican pine. A small flock of greenfinches were feeding on the cones. When I first noticed the sound, I had a short-lived hope that the pine tree might have attracted some crossbills. These are finches, related to the greenfinch, which use the uniquely crossed tips of their bills to extract seeds from cones. They would have been a new, and quite unusual, species to record in my garden.

Nevertheless, the greenfinches were not without interest because they rarely eat cones. Some years ago, I was excited to see greenfinches feeding on the cones of cypress trees because my bird books did not record any kind of cone in the greenfinch's diet. Unfortunately, when I reported my observation to the author of a book devoted to finches, he told me that the habit had been recorded since the book had been written!

The real significance of these observations is that they show the adaptability of the greenfinch. Its diet, primarily of seeds, is the broadest of any of our finches and ranges from thistle seeds to the small, hard nuts of hornbeam trees. Greenfinches have also taken to feeding on sunflower seeds and peanuts in greater numbers than other finches. Extracting seeds from cones requires very dextrous use of the bill but greenfinches must also be willing to experiment and learn. They have to look for ripe cones which have opened to reveal the seeds, as they have learned to attack the fruits of merezeon, a garden shrub, before they are ripe, when the stones are still soft.