Measurements
Both Sexes
Other Names
- Crossbill, Common Crossbill (British)
- Béc-croise des sapins (French)
- Pico cruzado (Spanish)
Cool Facts
- The Red Crossbill is so dependent upon conifer seeds it even feeds them to its young. Consequently, it can breed any time it finds a sufficiently large cone crop, even in the depths of winter.
- Because this species can breed throughout most of the year, its molts and plumages vary more than those of other North American passerines. Juveniles hatched during summer molt only between late summer and late autumn (at the same time adults molt). Many (but not all) juveniles hatched earlier (from late winter and early spring) begin to molt 100-110 days after hatching and then again during the main molt period in the summer.
- A crossbill's odd bill shape helps it get into tightly closed cones. A bird's biting muscles are stronger than the muscles used to open the bill, so the Red Crossbill places the tips of its slightly open bill under a cone scale and bites down. The crossed tips of the bill push the scale up, exposing the seed inside.
- The Red Crossbill shows a great deal of variation in bill shape and voice, and it may in fact be composed of several different species. Eight different flight call types have been described north of Mexico, and birds giving each type have slightly differently shaped bills and prefer to feed on different tree species with differently sized cones.
Habitat
Forest
Mature coniferous forests.
Food
Seeds
Conifer seeds, especially spruce, pine, Douglas-fir, and hemlock.
Nesting
Nesting Facts
- Egg Description
- Whitish, with reddish streaks and splotches concentrated around large end.
- Condition at Hatching
- Helpless with sparse down.
Nest Description
Open cup of twigs, lined with grasses, lichen, conifer needles, bark shreds, hair, plant fibers, and feathers. Well concealed in dense cover on branches of coniferous tree.
Nest Placement
Tree
Behavior
Foliage Gleaner
Hangs on cones and extracts seeds with oddly-shaped bill. Feeds in flocks. Takes grit and salt from roads.
Conservation
Least Concern
No reliable estimates available of population numbers because of nomadic movements. Populations appear to be stable in most areas. May be declining in Pacific Northwest rainforests where deforestation is rapid. Formerly common in Newfoundland; now rare, possibly extirpated because of competition with the introduced Red Squirrel.
Credits
- Adkisson, C. S. 1996. Red Crossbill (Loxia curvirostra). In The Birds of North America, No. 256 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.