This is Bird Note.

Safety is everything for birds during breeding season.

Be it of the eggs, the chicks, and even the mother,

so nests must be well hidden.

In fact, nests often blend in so well with the background

that they're very difficult to see.

But do birds deliberately choose materials

that camouflage their nests?

To find out, a team of biologists from the University

of St. Andrews in Scotland studied male zebra finches,

tiny Australian songbirds with smoky grey heads,

stubby red beaks, orange cheeks, and black and white tails.

Peaceful and friendly, they are popular both for research

and as pets.

The scientists wallpapered the finches' cages

with one color of paper.

Then they gave the birds two differently colored materials

to build their nests.

For the most part, the finches chose to build with materials

that matched the walls of their cages.

But many of the zebra finches also used small amounts

of materials that weren't the same colors the walls.

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