I love chickadees. Who doesn’t? How drab our winters would be without these little cherubs of the snow!
Although this winter has been exceptionally mild, most winters severely challenge the survival skills of our resident birds. Cold weather is especially demanding for chickadees and other small birds because of their diminutive size. To keep their small but highly revved gas tanks full, they must spend their waking hours in a ceaseless quest for food.
You may notice that chickadees visit your feeders in flocks. These are loose flocks consisting of about a dozen adults, each of which has forsaken its smaller breeding territory in favour of a much larger (about 20 acres) winter territory.
With these adults are juveniles from other areas. Winter flocks rarely contain parents and offspring from the same family. While flocks usually keep within the confines of their territories, lively skirmishes will result if they are caught intruding into the domain of another flock.
Chickadees have a remarkable vocal repertoire of about 15 different songs and calls. Calls are what we hear at this time of year, issued so they can keep in touch with each other or alert other members of any potential threats.
The most classic “Chickadeedeedee” is used year-round and is usually given when there is a disturbance, when one bird has become separated from the flock, or to alert the rest that danger has passed.
To keep in touch with each other, they utter a “Tseet” sound and, should a predator approach, they issue a sharp “Tsee Tsee Tsee.” Thanks to the recent mild weather, males can sometimes be heard singing their classic “Cheeseburger” mating song. This song is always heard in the spring, but, as if confident that spring is just around the corner, they will also sing their hearts out on warm and sunny mid-winter days.
To survive our cold winter nights, chickadees eat as much as they can just before nightfall so their stomach contents can sustain them until daylight.
If temperatures are fairly mild, a flock will roost together in the dense foliage of evergreens. On colder nights, each chickadee sleeps alone in the snug confines of a pre-selected winter roost cavity. On very cold nights the birds further conserve energy by going into nightly hypothermia.
Finally, during extremely bitter temperatures, they will plunge under the snow (like grouse) in order to take advantage of the insulating snow pack.
Myrna Pearman is the Biologist/Site Services Manager at Ellis Bird Farm. She can be reached at mpearman@ellisbirdfarm.ca