Sunday, June 1, 2008

Tiny Voyagers

Late in March each year they gather in large numbers on the telephone wires near the outskirts of Grover City, California, about a hundred miles north of Los Angeles. It’s a scenic spot, with the blue Pacific on the west and the Sierra Madre Mountains a little to the east. Excitedly, through vocalization and body language only understood by others of their kind, they encourage their companions for the great adventure ahead. Then, one morning, they’re gone.

Ten days later, after crossing the high desert and skirting the southern limit of the Sierra Nevada’s, they’re in Elko, Nevada, and a week after that they cross the Salmon River near the little town of Burgdorf, Idaho, under the light of a full moon.

By the first of May, the flock has crossed the Bitterroot Mountains in western Montana and is about to enter southern Alberta near the town of Cardston, but they are beaten back by a late spring snowstorm. They retreat southward a hundred miles to the shelter of one of many isolated river valleys where flying insects are abundant.

As the warm south winds return, the flock cruises high above the central Alberta countryside. Beneath their wings farmers are in their fields busy with the planting. Commuters on the highways and seismic crews on the cut-lines are oblivious to their passing. The tail winds are stronger at altitude, and they are spurred on by an instinctive urgency to find their summer range, but they still have a long way to go.

On the twelfth day of May they fly high across the Alberta border and into the Northwest Territories, spending several days in Hay River, resting for their journey across the big lake. The local residents, too busy with flood clean-up, don’t notice them. A few pairs stay behind, but the majority moves on, across the still-frozen, lifeless lake. Four hours after leaving Hay River the flock arrives in Yellowknife, where the micro-climate of the small city has spawned enough flying insects to satisfy their hunger.

Again, a few pairs stay behind to feed, build their nests and raise their young, but some go on. They are the pathfinders, legends among their kind, extending the range of their species beyond what the bird books proclaim as the limit.

Within a few days, they’re crossing the scraggly, black-spruce taiga country, following that sparse forest north along the Coppermine River. Tentatively, a few go even farther, finding their birthplace under the eaves of a hill-side, two-story house overlooking the Arctic Ocean. But it’s too early. The scouts return south to the main body of the flock near the arctic circle, and they all decide to remain in the shelter of the trees until warming temperatures on the coast bring out enough flying insects to allow simultaneous feeding and nest-building.

And so they arrive each year – the scouts around Victoria Day and the rest of the flock about the first of June. There follows a flurry of mud-finding, mud-carrying, nest-building and feeding.

Each year, when “my” swallows return to their birthplace, I feel a mix of awe and humility. Certainly, it is a great privilege to have these amazing birds nest on my house. Their adventurous and dangerous lives make those of mere humans seem pretty tame by comparison. They travel farther in a few weeks than I could walk in a couple of years. They fly with a degree of skill that the best fighter pilot would envy. A human-being with a multi-billion dollar GPS system at his disposal could navigate no better than my swallows, and no atmospheric scientist can predict the weather and winds as well as they can.

But their adventurous lives are short and often brutal. Starvation and hypothermia are constant companions. Sometimes they collide with cars or power lines or fall prey to a falcon. Sometimes their tiny hearts just capitulate, overcome by a life of constant activity with little time for rest.

When they arrive at their summer residence overlooking the mouth of the Coppermine River, their problems have only just begun. They must find and carry the mud for their nests, a tiny mouthful at a time, often from miles away. Hundred of trips may be necessary to repair a house, many more to build a new one from scratch. An early summer cold snap that lasts more than a few days can cause starvation and newly-laid eggs to be abandoned, wiping out an entire generation of young. A late-summer wind and rain storm can destroy nests, and the young contained there-in. Humans see the tragedy of it all, but the swallows simply get on with their lives – perhaps next year will be better.

But there are successes too. Most years, more swallows leave than had arrived a couple of months previously.

In late August, after waiting several days for the last of the fledglings to take wing, they will sit in rows on the cable-TV wire over our driveway, chattering excitedly and encouraging their young for the great adventure ahead.

Then, one morning, they’re gone.


Photo: Cliff Swallows winter in the southern United States, Mexico or Central America, and some spend their summers beyond the arctic circle.