One of the many things I love about bird watching is the continual opportunity to learn new and surprising things—even about some of the most regular visitors to my feeders. One of these opportunities (I call them AH-HAH MOMENTS!) occurred last May when I began to notice an unusual bird at my sunflower feeder. Small and almost dumpy looking, this bird was slightly larger than a sparrow, brownish in color with a very stripy chest and a slight yellow cast to its back. My identification process led me to consider the female house finch and various members of the sparrow family but none seemed right and I continued to be puzzled until one day when a female Red Crossbill appeared next to this little mystery bird and began feeding it with the seeds from our sunflower feeder. It was only then that I realized that my little “mystery bird” was a newly-fledged Red Crossbill. What I had thought to be a lethargic or even a sick bird turned out to be one not yet quite comfortable with his wings, waiting patiently for Mom to appear with his next meal. Of course, then I realized that I had failed to notice the most significant identification feature of this little bird—the crossed tips of its mandibles. Also, because it was only mid-May, I hadn’t even considered that I might be seeing an immature bird. Well, this whole experience certainly proved once again that I still have a lot to learn about the birds of our area, but I also came away with a lot of great new information about Red Crossbills which I’ve decided to share with you this month.

A member of the finch family, the Red Crossbill is slightly larger than the House Finch and adult males tend to be red or orange in color with black wings and tail, while females are yellowish with grayish olive wings and tail. At a distance, Crossbills can be differentiated from House Finches by their stockier shape and their larger heads. At close range, the most distinguishing feature of the Red Crossbill is its crossed mandibles which allow it to pry the seeds from conifer cones. Since birds’ biting muscles are stronger than the muscles that open the bill, the tips of its slightly open bill are placed under a cone scale and when it bites down, the crossed tips push the scale up, exposing the seed inside. While Red Crossbills are mainly resident, the population may erupt south if its food source fails. Because they feed primarily on seed cones, Red Crossbills live mainly in coniferous forests. According to Sibley, at least nine forms of the Red Crossbill occur in North America with the various forms differing from one another in their average bill size and structure, body size and their flight and alarm calls. Generally referred to as call types, these different forms reflect the preference for cones of a particular type of conifer. In general, the larger and stouter bills types forage more efficiently on the larger and harder cones such as those of the pines, while the smaller-billed types feed most efficiently on smaller and softer cones such as those from spruce, firs and larch. The different forms rarely, if ever, interbreed. While ornithologists agree on the existence of these types, there has not yet been a decision as to whether the forms should be regarded as separate species.
 

Interestingly, because the Red Crossbill is so dependent on conifer seeds, it even feeds them to its young and consequently, it can breed any time of the year that it finds a large enough cone supply, even in winter. Nests are made of twigs and grasses and placed on tree branches. The 2 - 5 eggs are greenish-white or bluish-white with dark marks. Hatch occurs in 12 – 18 days and the young fledge 15- 20 days after that. Parents continue to feed the newly fledged babies regurgitated seeds – either from cones or in the case of the ones I observed, from my sunflower seed feeder—for several weeks.

Because of their sporadic breeding pattern, the Red Crossbill’s molts and plumages vary more than those of any other North American songbird. Juveniles hatched during the summer molt between late summer and late fall, as do the adults. Most of the juveniles hatched earlier (late winter to early spring) begin to molt approximately 110 days after hatching and then again during the main molt period.

Watch for these interesting and beautiful birds any time you’re in a coniferous forest. They can typically be spotted in small groups, flying from tree to tree, feeding on the cones. At our house, they’ve also often been frequent visitors to our black oil sunflower seed feeders and also to the water sources which we offer all year long. As I mentioned earlier, they brought their young to our feeder starting in May and I continued to see newly fledged Crossbills until mid August. Today, as I am finishing this article, a flock of about twenty Red Crossbills have arrived at our bird bath to enjoy the water and I’m pleased to see that this flock of twenty or so includes seven or eight juveniles. I hope that despite the drought of the summer, our Larch and Douglas Firs have produced enough cones to keep this active group around for the winter. Their arrival always brightens my day!