How many blowholes do baleen whales have?

Baleen whales have two blowholes, arranged as a pair near the top of the head.

A blowhole is the whale’s nostril, repositioned over millions of years so the animal can breathe while keeping most of its body submerged. When a baleen whale surfaces, it forcefully exhales through both openings before inhaling fresh air. The visible “blow” is mainly warm, moist breath condensing in cooler air, sometimes mixed with water resting around the openings.

The two blowholes are separated by a muscular septum and are positioned in a V-shaped arrangement. Plugs and surrounding tissue help seal the passages during dives, preventing water from entering the respiratory system. The openings are not gills: whales are mammals and must breathe atmospheric oxygen.

This is a useful distinction between the two major whale groups. Baleen whales, including humpback, blue, fin, gray, right, and bowhead whales, have two blowholes. Toothed whales, such as dolphins, sperm whales, and orcas, generally have one. Blow shape and timing can also help researchers identify species at sea, although weather and viewing angle can make the pattern difficult to see.