The fall migration is on the decline now with most of our flycatchers, swallows and warblers gone for the next seven months. All of these birds depend on insects for their sustenance, a resource in short supply now.

Sparrows and other seed-eaters have a more leisurely migration. They can find seeds, at least until the first snows arrive. Even so, by the end of the month most of our sparrows will be gone to more moderate southern areas.

As I discussed in the last column, we know that the majority of migratory bird species have an innate knowledge of where they should go to spend the winter. It boggles the mind to realize that many first-year birds find their way unaided by adults to their wintering habitat they have never seen. Travel instructions are encoded in their genes.

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