House Sparrows are a common sight in many backyards. Their constant presence and invasive designation makes them easy to overlook, but they can be an entertaining study, especially going into the fall as they change their appearance. Most of our native species need to molt (or replace) their feathers twice a year: once in the spring to get their breeding (or alternate) plumage, and again in the fall for their non-breeding (or basic) plumage. House Sparrows, in contrast, only molt once annually, in the fall. A fun feature to study is the breast feathers on the males, who typically look like they’re wearing a dark bib. These newly-replaced feathers will have pale gray tips to them, representing this bird’s non-breeding plumage. Those tips will wear away over the winter and reveal the complete black bib by spring, then it’ll be in its breeding plumage! Molting takes a lot of energy, so this two-for-one technique is quite the helpful adaptation.
Backyard Bird of the Month is a feature by Maine Audubon created for the Maine Home Garden News, the newsletter of the University of Maine Cooperative Extension: Garden and Yard
Photo by Doug Hitchcox