The fall raptor migration is under way and there is no better time to view these birds, which are ordinarily inconspicuous during the breeding season. Except for one individual I encountered last summer along the University of Maine bike path.

The unmistakable high-pitched whistle of a broad-winged hawk brought me up short. Almost directly above me, a young bird perched and called repeatedly from a birch tree.

I saw that it was a juvenile, and, as do the young of all species, seemed not to care that it was calling attention to itself. In fact it was making quite a racket. Presently it was answered by two more broad-wingeds – adults – that began to circle above the treetops. I thought it possible that they were the parents and that the youngster had recently fledged from the nest.

Soon the young bird, which had probably taken its first flight from the nest not long before, would be undertaking a grueling marathon journey. It would fly hundreds, if not thousands of miles to its wintering grounds – without the guidance of its parents.

The young bird would depart toward the end of August and the beginning of September, flying best and farthest on north winds and clear days. At first, it would follow the Atlantic shoreline, especially if strong, northwesterly winds prevailed after the passage of a cold front.

Ornithologists are unsure if these conditions are conducive to migration or to simply bringing the birds to where we can see them; nevertheless, it is when the highest numbers of raptors are seen at lookouts such as Cadillac Mountain here in Maine.

In northern New Jersey, it might turn inland and follow the southern Appalachian ridges before heading in a southwesterly direction.

Once it reaches eastern Texas, it could travel south to fly around the Gulf of Mexico to its final destination of southern Mexico, Brazil or Bolivia. Or, perhaps the bird would instead continue down the eastern U.S. seaboard to spend its winter in southern Florida and the Keys with the rest of our “snowbirds.”

It is an incredible journey. The young bird I saw would navigate an unfamiliar route using different flight strategies in varying weather conditions. Throughout its journey it would also have to feed itself and find protective shelter within which to rest during the night.

If its journey were delayed due to bad weather, it might find itself in habitat lacking adequate prey and could starve to death. Any number of things could happen – the modern world is full of danger for a migrating bird.

I wonder if that young bird ever made it, and if it returned this past spring. If it did, it would now be on its way once again – his time flying toward the path of Hurricane Isabel.

It is an incredible journey.

Chris Corio, a volunteer at Fields Pond Audubon Center in Holden, can be reached at fieldspond@juno.com