Thursday, 13 September 2007

Woodpecker signs: cones

Conifer cones worked on by woodpeckers, to obtain the seeds inside, are opened in a different manner from those fed on by mammals. The cone scales are broken lengthways and have a jagged, ruffled appearance. Piles of such cones are often found below anvils or single cones found wedged in cracks. Woodpeckers fly with cones to anvils, wedge them, tip upwards, and work them systematically, turning them around in order to open upon the scales around the whole cone. Cone scales are prised open sideways to get at the seeds. This causes the distinct ruffled appearance. Cones are not damaged on the base of the cone, where they are wedged into anvils and where the scales are also tighter. It has been calculated that it takes a Great Spotted Woodpecker around four minutes to empty a cone of its seeds and in this time the cone can be pecked some 800 times.
The phot here shows a conifer cones wedged into a tree crevice anvil by Great Spotted Woodpecker in Budapest, Hungary (Szabolcs Kókay)

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