the contemplative nuthatch

A pulse of life is rippling through Sapsucker Woods. Amid the screeching blackbirds and honking geese it is now possible to discern the melodious tones of a host of wood warblers, buzzy phoebes, even monotonous vireos. All this noise is presaging one thing: it’s time to breed! And there’s already evidence that breeding is occurring across a wide range of birds right under our noses: at one end of the spectrum, the rotund massiveness that is the Canada Goose, and at the other end, our petite Black-capped Chickadee

There aren’t many similarities that come to mind when comparing Black-capped Chickadees and Canada Geese. One can weigh in excess of 5000g (or 11 lbs!), the other tops out at ~12g (the weight of two quarters in your hand!). Geese migrate long distances in family groups, chickadees stick it out for the winter across most of their range. And despite both of these species being grossly different, they actually share a number of fine details that allow them to succeed as early-season nesters:

• Both begin nesting in the early spring: Geese are able to breed through the cooler spring temperatures thanks to their massive bodies, which generate sufficient heat to keep themselves and their eggs warm. Chickadees use a different tactic, utilizing the wooden insulation of a tree cavity to avoid the elements.

• Both leave the nest at around 28-30 days…but baby geese and baby chickadees are worlds apart!  Goslings are precocial: when they hatch out, within 24 hours they are motoring around on their own, foraging for themselves, but still needing mom or dad to thermoregulate.  Chickadees, on the other hand, are altricial: their first days are spent blind and helpless, hatching out of their eggs in ~14 days.  When they leave the nest (at around 30 days) they are able to fly, are fully feathered, and able to (somewhat) fend for themselves (click here for neat video from a chickadee nest, thanks to Project NestWatch). Young Canada Geese take another 6-10 weeks before finding themselves aloft…

• Both are fiercely territorial! The sweet clear “fee-bee” whistle of the chickadee begins in early Spring as the dominant males begin to jockey for the best woodland locations and nest cavities.  Geese act similarly, waiting for the water to open then engaging in protracted battles that often result in a loss of feathers for the losers and ceremonial posturing for the winners.  This territoriality is important in securing the resources that are needed for a successful nesting attempt.

Leave me a note in the comments if you come up with other natural history similarities among these two modestly plumaged birds…