While some may believe it is water that they’re spurting out of the blowhole, it’s actually something else entirely. Blowholes, at the top of the whales head, are basically giant nostrils that exhale old air to suck in fresh air at the water's surface. When whales are exhaling or 'spurting' from their blowholes, they’re clearing their airwaves through their gigantic nostrils. What comes out is a mix of water vapour and plenty of whale snot.