Have you noticed that fewer birds are singing this time of year? At my house, the dawn chorus of spring and early summer mornings has been replaced with an occasional caw from the local crow family or quirrr from the red-bellied woodpecker.

As summer winds down and the nesting season closes, the territorial and courtship songs of our region’s avian population are silent.

From August through September, each morning seems to be quieter and quieter as the volume of the chorus diminishes.

In the spring, we experience the sudden arrival of songbirds in March and April. It seems as if one day our usually quiet winter morning is interrupted by the explosion of singing, calling and chirping.

Each spring the urge to reproduce drives birds north to their nesting grounds in our region, and in autumn that migration is reversed.

Unlike the burst of spring arrival, the fall migration is a quiet process, unnoticeable unless you take the time to look closely.

This morning as I was leaving the house I saw about a dozen birds flying about the maple trees in my yard. I paused to see what birds they were and was surprised to see flashes of blue mixed with the yellow and orange of the maples’ fall foliage. Bluebirds! Our maples were full of bluebirds.

Readers of this column know that I like to write about the bluebirds that reside in the nesting boxes at my house. All spring and summer I enjoy watching as they bring insects and caterpillars to their brood.

To see them joined this morning by so many other bluebirds was a delight. Perhaps some of them were nestlings from our pair, or from other nests in our neighborhood.

Something was about and I surmised that this veritable bluebird congress had assembled to plot a group escape to warmer climes.

Diet is the primary factor that determines when songbirds such as our family of bluebirds begin their southern migration.

Many species of flycatchers and warblers are insectivores and rely on bugs. As the bug population diminishes they head for warmer, “buggier” climes to the south.

Other species of birds, such as sparrows, are omnivores that eat fruits, seeds and insects. They have more dietary choices and can stick around longer, well into the fall and early winter.

I witnessed this last week while hiking on the Nipmuck Trail in Ashford, when I saw several robins gorging on wild grapes. The grape vines had twisted their way up into several oak trees near the trail and the sweet ripe fruit must have been a nice break from earth worms!

Protein-rich insects and worms are the perfect food during the spring breeding season for the growing nestlings. Seeds and fruits are scarce in the spring but plentiful in the fall as the birds prepare for migration.

These foods provide important energy and become stored fat that is needed for surviving the difficult southern migratory flight of hundreds or thousands of miles.

October is slipping into November and the days are getting shorter. The mornings are cooler and much quieter now.

I sit outside with my coffee and watch the seed eaters — nuthatch and chickadee, tufted titmouse and woodpecker — alight on my freshly-filled bird feeder. Each will be a welcome guest throughout the winter months.

Oct. 15 brought the first frost of the season at my house. The grass is slowly being covered by maple leaves and the oaks are being worked over by busy squirrels gathering acorns.

Slowly the fall season turns and the winter migraters depart. One by one or in groups of many, they’ll make their way to warmer regions where food is more plentiful.

I’ll wait in anticipation for their return in six months. As the snow flies and ice forms I look forward to that morning when my slumber is interrupted by their musical arrival.

Until then, I’ll appreciate the many birds that make The Last Green Valley their year-round home.

We live in a beautiful place full of amazing wildlife. To understand bird and animal habits is to appreciate all we have right outside our doors.

I hope you’ll join me in caring for this beautiful place, to enjoy it and celebrate it each and every day. Together we can pass it on to the next generation.

Bill Reid is chief ranger of The Last Green Valley National Heritage Corridor and has lived in the region for more than 30 years. He can be reached at bill@tlgv.org.

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