Book 31, Question 46
Why can some diving birds close their nostrils?
Gannets and cormorants dive from the sky or from the water’s surface into the sea.
If water rushed up their nostrils, it would be uncomfortable and could hurt. Gannets have no outside nostrils, and cormorant nostrils are very narrow and sealed shut. Both birds breathe through the corners of their mouths. This keeps water out and lets the birds dive without a problem.