Show Details

Insects vs. Birds

March 2, 2016

The loud noise of insects causes some tropical birds to delay the onset of their morning song.

Transcript

InsectNoise1_PhotoCredit_Andrew Foss-Grant

Recording the dawn chorus of birds on Barro-Colorado Island in Panama. (Andrew Foss-Grant)

BOB HIRSHON (host):

Insects vs. birds. I’m Bob Hirshon and this is Science Update.

(Dawn bird chorus)

As the sun rises in the tropics, the air comes alive with bird song. But the dawn chorus is no random assortment of voices. University of Maryland animal ecologist Calandra Stanley reports in Animal Behaviour that birds with high-pitched voices start singing later than other birds. This could be to avoid being drowned out by loud nocturnal insects, which overlap them in pitch.

CALANDRA STANLEY (University of Maryland):

In order to save energy, because there’s no point in singing as loud as you can when there’s so much noise from insects.

HIRSHON:

But Stanley says these birds join in the dawn chorus once the insect noise dies down for the day.

STANLEY:

As they, you know, decide to go to bed.

HIRSHON:

She adds that just playing recordings of cicadas – one of the loudest animals in the rainforest – is enough to silence birds that overlap them in pitch. I’m Bob Hirshon, for AAAS, the science society.

Story by Susanne Bard