Monday, September 3, 2007
Anvil, smithies, workshops
There is a new development in my local Syrian Woodpecker observations. The birds have wedged a walnut in a joint between two boughs on the biggest false acacia tree in the garden. This is known as an anvil (sometimes termed “workshop" or “smithy"). The anvil is a crevice or crack in a tree, log, post or even a wall, where woodpeckers wedge and process hard food items such as nuts, cones, fruit stones and large insects. Great Spotted, Syrian and possibly Green Woodpeckers use anvils. Nuthatches do this, too, but an important difference between anvils used by Nuthatches and those used by woodpeckers is that Nuthatches only use an anvil once, thus no piles of debris accumulate beneath it, whereas woodpeckers use favourite anvils repeatedly. Great Spotted Woodpeckers are unique in creating customised anvils to suit the food item regularly fed upon in an area. Anvils are often used for long periods hence debris, cones, nutshells, hard insect remains, accumulate beneath them. Sometimes trees with several crevices used as anvils are dotted with wedged cones and nuts and in winter take on a strange Christmas tree appearance. Beside walnuts, the stones of plums, almonds, cherries and apricots are often wedged in anvils by Syrian Woodpeckers.