Spanish term for "birdwatching"?

I am going on a birding expedition to a Spanish speaking country.

What do they call the hobby of birdwatching in Spanish? Online translators are giving me “observacion de aves”, is that it?

Is it a popular hobby among Spanish speakers themselves, or is it mostly crazy Americans and Brits who do it?

“observacion de aves” is correct, it refers to the act itself, “observar” means look or watch. A bird watcher is called “observador de aves” and there are enough of them to warrant the publication of guides:

http://www.agapea.com/GUiA-DEL-OBSERVADOR-DE-AVES-n85611i.htm

http://www.lsf.com.ar/libros/1/950240645.html?vienede=yaguarete

Yes, *observador de aves * would be best.

Sometimes I have seen “birding” translated as pajareando (derived from pajaro), bird) but this is best avoided as it is close to a slang term for masturbation.