I hope all of you enjoyed your Christmas and New Year holidays.
The Christmas Bird Count was one of my favourite activities. When one of the birders asked me about a flock of birds that he was not sure of, I realized that his description of how the flock was flying is one of the good clues to identifying that species — the common redpoll — a very common bird found at northern latitudes even through severe winter weather.
The flock was described as flying in a tight group in swooping, rounded circles. In addition, there were lots of birch seeds on the ground. Birch seeds are a staple for redpolls (both common and hairy) in winter because their protein content per unit weight of seed is very high which helps the birds survive cold winter days and nights in northern climes.
It is no surprise that birches grow up into far northern latitudes.
I also discovered something completely new to me as I was reading about them. They go after the seeds in three phases. Phase I is to ‘acrobatically’ knock down the seeds from the birch catkins onto the ground that is often snow covered.
In Phase 2 they drop to the ground, pick up the seeds off the ground or snow and put them in their diverticulum. The diverticulum is an internal, pouch-like extension of the esophagus where birds can store food to be consumed later e.g. on a cold winter’s night.
The birds then fly to a sheltered place (Phase 3) where they are better protected from predators and cold and can eat the stored seeds at a more leisurely pace. redpolls and crossbills usually seek shelter in the dense foliage of conifers where they fluff out and huddle close together.
Redpolls are known to be able to survive lower temperatures than any other songbirds. They are commonly seen in large flocks during northern winters.
They also like to bathe in snow.
The word poll means the top or back of the head, i.e., the birds have a red topknot.
