“If it’s November, those must be red-tails.”

So begins the essay, “On a Wing and an Updraft: Hawk Migration, Connecticut” found in A Journey for All Seasons, written by John Kinch and published by The Nature Conservancy, 2000.

This piece is all about bird migration, an event that takes place every fall and then every spring in the life of many bird species.

The reason we don’t typically see the same birds year round at our homes is that they migrate, moving south to find food sources. Many migrating birds eat insects or fruit, not available year-round in most of North America.

Those birds that do hang out in our backyards year-round survive on nuts, or small insects and creatures living in leaf piles or just barely under the surface of the earth.

But I’m getting off track. This time of year, late November, watch for the last of the hawks flying south.

“The timing of hawk migrations in various parts of the country tends to be consistent, although extremes in weather and other natural vagaries can delay or even accelerate migration by several weeks. For hawk watchers, September can mean mostly broad-winged hawks, October, American kestrels, November, goshawks.

“By November, at the Nature Conservancy’s Devil’s Den Preserve in western Connecticut, the migration of raptors (hawks, falcons, vultures, and eagles) tends to be dominated by the accipiters, woodland hawks that prey on small birds and animals. Among these are the goshawks, Cooper’s hawks, and sharp-shinned hawks. Two species of buteos (larger, stockier hawks) are also present: red-tailed and red-shouldered hawks.

“In the fall, as broad-wings make their way south, they gather into flocks that sometimes number in the thousands. They soar on thermals – warm upward-rising air currents. To use the thermals, the hawks circle, rising ever higher, forming what looks like from the ground a huge kettle in the sky. Once they reach their desired elevation, they pull out of the ‘kettle’ and soar in a straight path, falling slightly until they reach another thermal and ‘kettle’ up again.”

MIGRATION FACTS:

• Migrating birds fly most frequenly at an altitude roughly between 1,500 and 2,500 feet. A flock of whooper swans were once observed flying at an altitude of more than 28,000 feet – a height favored by jet planes.


• Birds migrate day and night. Generally, passerines (songbirds) travel by night and birds of prey (raptors) by day.


• The main wintering grounds for North American birds is Mexico and Central America. Nowhere else is there such an extraordinary concentration of wintering birds – underscoring the importance of habitat preservation in these places.