On three occasions over the last couple of weeks I have seen a great spotted woodpecker fly to a copper beech and spend several minutes hammering at one spot. I assumed that it was chipping holes to get at insects - until the third time. The woodpecker moved up the trunk to reveal a pale spot just below it (see photograph). On investigation, I found the empty shell of a hazel nut wedged in the bark. We read so much of the marvellous way that woodpeckers are adapted for chiselling insects out of rotten timber that, despite their regular appearances on peanut feeders, it seems incongruous that they should feed on hazel nuts. Tree seeds are important winter food, especially in northern Europe where cones of pine, larch and spruce are the staple. Cones, hazel nuts and seeds of hornbeam and other trees are wrenched off the tree and carried to an 'anvil' where they are hammered open. The cone or nut is wedged into a crevice which the woodpecker may open up by chiselling. Some anvils are used once only and others are used repeatedly. One interesting point is that the woodpecker should go to the trouble of detaching hazel nuts, carrying them to the beech and spend several minutes opening them when it is well aware that there are plenty of easily-obtained peanuts a few yards away. I have noticed that no birds feed wholly at the feeders. It seems to be a fundamental part of their foraging behaviour not to rely on one source of food.
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