Fledgling birds learn life's lessons on the fly

A young robin, not quite two weeks old, jumps off a branch and settles on the leaf litter below her nest tree. In just a few hours, her three siblings follow suit, fluttering downward, then scuttling under low-hanging branches for safety. They'll hop on the ground for several days, until wings and flight muscles develop.

Their bluebird cousins spend about a week longer in their nest cavities than robins do in their open nests. During that extra week they become significantly stronger and better prepared for the outside world.

Fledgling chickadees flutter from their nest holes, then flit from tree to tree and shrub to shrub, their bright eyes watching everything in their new world. Adult chickadees must collect insects, then track down their perpetual-motion chicks to feed them, hour after hour.

We tend to think nesting season ends when young birds launch into the world, but in truth, the job is only partially completed for most bird parents. It could even be argued that some adult birds work even harder after their brood disperses.

Back to those robins that left the nest before they could fly: They had to go, since there was no longer room in the nest for four growing chicks. And all that going back and forth by the parents and the chicks' "Feed me!" screeches make it easy for a predator to locate an easy meal. Fledging before they're flight-able is a good strategy.

With room to stretch their wings and time to build strength in their legs and feet, young robins are soon scurrying across the lawn, jabbing at earthworms, just like Mom and Dad do.

The two big tasks of a fledgling's life are learning to feed themselves, a complex task, and avoiding predators (at this stage, the biggest dangers are cats and hawks). It all boils down to one simple but vital mission: staying alive while learning to live on their own.

Cedar waxwing juveniles are drab, stripy youngsters, barely hinting at the beautiful birds they'll become. One of the ugliest ducklings in the songbird world is a fledgling cardinal, with brown beak, brown feathers and a raggedy crest.

There are exceptions: Young chickadees look much like adults and blue jays closely resemble their parents, as do hairy and downy woodpeckers. Young gray catbirds are all gray, and house wrens look like wrens. But camouflage, or at least the lack of bright feathers, is the norm.

Young birds try a great many things that either aren't nourishing or are unpalatable before they develop a mental menu for their species. Consider the young Baltimore oriole I saw chase down a flying insect earlier this summer. It swallowed its prey, and then promptly threw it up, doubtless making an indelible impression on the bird.

By autumn, summer's youngsters must be ready to meet the challenges of life on their own, because in most cases their parents departed some weeks before. They'll either face winter's cold and scarcity, if they're resident birds, or they'll fly, sometimes long distances, to a warmer climate where they'll need to learn new lessons about "locavoring."

So much to learn, so little time. It's a wonder that young birds survive at all, and many don't. But if they can make it through their first year, either through a long winter, or a migration round trip, they've earned the chance to see many more summers.

Juvenile hummingbirds often weigh more than their mothers when they leave the nest. After all, they've spent almost three weeks being "nest potatoes," consuming a rich slurry of plant nectar and tiny insects brought by Mom. After flapping their wings for hours to build up flight muscles, they shadow their mother, learning to hover in place and lap up nectar, both complicated tasks. (The female hummingbird provides life lessons for her first brood even while starting her second, with no help from the birds' father.)