How many blowholes does a sperm whale have?

A sperm whale has one blowhole. Unlike baleen whales, which generally have two blowholes, the sperm whale’s single opening sits slightly left of center near the front of its enormous head.

The sperm whale is a toothed whale, and its blowhole is anatomically the whale’s left nostril. The right nasal passage is highly developed internally but does not open separately at the surface. This unusual arrangement produces the sperm whale’s characteristic bushy, forward- and left-angled spout.

The one-blowhole design is easy to mix up because many familiar large whales, including humpbacks and blue whales, have paired blowholes. The number of blowholes reflects the major division between baleen and toothed whales, although the sperm whale’s anatomy is especially distinctive.

Sperm whales can remain underwater for long periods while hunting deep-water prey such as squid. Before a dive, they may breathe repeatedly at the surface; after surfacing, their noisy single blow can rise roughly two metres or more.