News and Opinion from Sisters, Oregon

Sisters Country birds

The Red Crossbill [Loxia curvirosta] is an erratic and nomadic bird that will flock to the tops of either deciduous or coniferous trees for a wealth of seeds. A highly variably colored species, the female is a yellowish golden, with the male exhibiting various shades of red.

Crossbills have a unique bill where the tips of the bill overlap to enable them to open conifer cones and seeds. With this skill, in seasons of plentiful cone production they may breed year round.

Red Crossbills are usually found in small flocks from six to 30 birds. They occasionally feed on aphids in deciduous trees, and some wild berries are also in their diet. The bills can cross in either direction, which in turn dictates which direction they feed on the seed cones.

With at least 10 different subspecies, each group uses slightly different flight calls to help identify and separate the different types. Monogamous pairs form within flocks, and the female will build the nest high on a horizontal branch within a conifer tree. A cup of grass, bark strips, and twigs begins the structure of the nest, which is then lined with feathers, lichens, and hair. A typical nest contains three whitish, reddish-streaked eggs, which are incubated for 12-16 days. The female and brood are fed by the male Red Crossbill for five days, and then the female joins the male in the feeding of the hatchlings for 18-22 days at which time the young fledge.

The young birds' bills are not crossed at birth but cross as they grow, and by 45 days they can begin to extract the seeds from cones. Crossbills can be seen on rocks gleaning minerals for healthy bills and bones.

A group of Crossbills is called a "warp" or a "crookedness."

 

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