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These gray-breasted sparrows are easily identified by their white throat patch and yellow spot between eye and bill. You may see them scratching on the ground beneath your feeder or hiding in shrubs. In the winter, White-throats tend to look alike, but in the breeding season, they show two distinct color forms. The white-crowned form has black and white head stripes, while the tan-crowned form has brown and tan head stripes. These color groups have genetic differences. When looking for mates, White-throats zero in on their opposite-colored morphs. In other words, the rule is: don't date anyone who looks like you! This phenomenon, negative assorted mating, probably ensures genetic variability in the population as a whole, and it is unique among birds.

Mating among White-throated Sparrows involves a lot of unrequited love, as well as aggression. Males of both color types prefer females with white stripes. How unfair that both kinds of females prefer tan-striped males! The more aggressive white-striped females may be able to outcompete their tan-striped sisters for the coveted tan-striped males.

As spring arrives, White-throated Sparrows will leave Jug Bay and return to their breeding grounds in Canada. We are fortunate that they spend the winter with us, singing their song, which may be an ode to their summer home: "Oh Sweet Canada Canada Canada!"

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