Juvenile Cliff Swallow waiting for a food delivery |
The adults flew in dizzying circles, delivering delicious insects to their nearly-grown chicks. The juveniles watched too, from the opening in each active nest, waiting for the next parent to bring yet another taste treat. This working stables wore a necklace of several dozen swallow nests under each eve. It seemed like a lot of birds to me, but the largest Cliff Swallow colonies in the west can number 3,700 nests or more.
Young Cliff Swallows born in Montana will soon fledge from their nests and form creches with other juveniles. By August almost all of them will be winging their way towards South America, where they'll spend the winter. Why migrate so early? Because they only eat live insects, so they have to leave Montana before an early frost depletes their groceries.