27 February 2017

On my trip to Costa Rica I wanted to see a laughing falcon. And then I wanted to hear it.

Laughing falcons (Herpetotheres cachinnans) are very vocal birds that live in Central and South America from Mexico to northern Argentina.  They specialize in eating snakes — even poisonous ones — which they kill by biting off the heads.  Ch’ol Maya legend says the birds can cure themselves of snake bites. And yet, the birds sound spooky.

At dusk laughing falcons raise their voices in advertisement calls or duets.  They start with a gwa call, getting louder and louder, that usually morphs into two syllables: gwa co.

One evening before dinner at Las Cruces Biological Station, Bert Dudley filmed this laughing falcon warming up at dusk. 

The two-syllable call gave the bird its common name, halcón guaco, but those calls don’t sound like laughing.

Here is his laugh:

The falcon only laughs when he’s worried or upset.

(photo and video by Bert Dudley)