You bet they do. They sleep quite differently than you and I though. Whales do not breathe automatically like humans. They must consciously inhale and exhale. Whales could not be in full unconscious sleep (the way we sleep) and actively decide to breathe. So this brings up the question of how a whale would breathe while when it sleeps. Scientists have come to the conclusion that whales rest only half of their brain when sleeping. This allows the whale to never be fully unconscious but still get the rest it requires to function. They sleep close to the surface of the water and breathe when required. The whales drift slowly near the surface, this action is known as “logging”. To find out more about whales hop on board, our 36 passenger catamaran, NANUQ, for a Whale Watching Tour. We have knowledgeable Naturalists as a part of our crew on our vessels. They know tons about whales and love to answer any questions our guests might have.