a most unusual finch

A bird that specializes in feeding on the seeds buried in pine cones has to have a nifty trick for extracting them, like a beak that works like a pry bar.  In the Common (or Red) Crossbills, the two mandibles that make up the beak do not meet at the tip, but cross over one another.  When the bird bites down between the scales of a pine cone, the tips of the mandibles push the scale open and the bird extracts the seed with its tongue.

Common (Red) Crossbill-

It might look as if the bird has an overly long upper mandible, but it is crossing over the lower mandible instead, giving the bird the ability to push the tips of the mandibles in opposite directions.  This bird was feeding on larch (tamarack) cones.

Strong legs and feet grip the cone as the bird works the scales open with its beak, curling its body around the cone and twisting its head to apply further pressure.

Common (Red) Crossbill-

Whatever position works best, even upside down.

Common (Red) Crossbill-

Check out those big feet and big beak at work!

Common (Red) Crossbill-

The birds usually start feeding at the bottom of the cone and work up in a spiral pattern to the top — the direction of the spiral depending on which way the mandibles cross.

Cone seeds make up most of a Crossbill’s diet, and they feed the seeds to their chicks as well.  As a result, Crossbills can breed and raise chicks any time there is a big enough cone crop, even during cold winters.  Young Crossbills, however, do not have crossed bills, but only develop them as they begin feeding on the cones themselves, about 45 days after hatching.

Crossbills usually feed on the cones high in the tree, but this bird must have been pretty hungry because it fed at eye-level for several minutes, completely ignoring the group of photographers honing in on the action.  (Photos above by Steve Chaplin)

photographing common crossbill-

the Crossbill is in the highlighted area in the tree

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