This is Bird Note.

Tree swallows glistened in the June sunlight as they swoop and glide their arcs, interlacing

in the air.

Add, Gile, elegant, masters of flight.

The swallows gather near their nest boxes, clustered on posts at the edge of a marsh.

A white feather flutters down among them.

When swallow snatches the feather in its bill and flies upward as another swallow gives

chase.

After a moment, the lead bird lets loose the feather, which drifts lazily until the second

bird swoops into catch it in mid-air.

The aerial ballet of swallows and feather swirls on for minutes as other swallows join

in the feather chase.

Are the swallows just playing?

Or are they competing for these feathers?

These feathers are an important resource for tree swallows.

They line their nests thickly with them, a feather bed for nestlings.

Continuing research suggests that, as tree swallows build their nests, it is the females

who collect the feathers.

Their aerial dance may well be a competition for nest-lining material.

And the males in the feather chase?

Maybe they're just playing along?

For BirdNote, I'm Mary McCann.

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