On a recent ice fishing trip to the Sawtooth Mountains of Idaho, I encountered a flock of birds, that were feeding on salt on the pavement of the road. Or perhaps getting a sip of water from the melting ice. This was near the top of Banner Summit at nearly 7,000 feet in elevation. The birds turned out to be the Red Crossbill (Loxia curvirostra), which have a body length of about 6 inches and a wing span of 11 inches.
They feed primarily on conifer cones, of spruce, pine and fir, but also eat the buds from trees. The Red Crossbill pries seeds from the cones using its highly adapted thick curved bill that is uniquely crossed. The perfect multi-tool. There are apparently 9 discrete populations of the Red Crossbill, which may be different species, and each type differs slightly in their voice or song or the size of their bills. Each type feeds prefers to feed on a select type of conifer tree, and they often mingle with other types.
There were about 12 birds in the flock I was watching. This area of the Sawtooths is heavily forested with conifer trees, mostly lodgepole pine, with spruce and subalpine fir along the creek bottoms. The ice fishing was poor that day, but the views of the mountains were spectacular. I am amazed how the Crossbill's can survive at such high altitudes in the winter, but the pine cones, are found high in the tree canopy well above the snow, and the seeds are there for the taking. Especially for the Red Crossbill with the perfect set of cone cracking mandibles. It sounds like a much easier way to obtain a meal than drilling through 3 feet of ice to find some wily trout.
2 comments:
The crossbills are great little birds. I saw my first ones in the UK.
They Crossbills are amazing...with the adaptation of their pine cone crunching bills. Some of those cones are almost as hard as a rock.
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