Whales - Species | Sperm Whale

Sperm Whale - Physeter macrocephalus

The Sperm Whale is generally well-known for two reasons. The first is its somewhat attention-grabbing name. In fact, the Sperm Whale was named after spermaceti, a milky substance found in the head, which was thought to be sperm before proper and extensive research had been carried out. The other reason that this is one of the better-known mammals is that it is the largest toothed animal currently in existence.

These gentle giants have a distinctly shaped body, and sizeable heads making up about one third of its body size. Males are about 20.5m in length. Unlike many other species of whale, the male is larger than the female – 30% to 50% longer, in the case of Sperm Whales. Males weigh up to 45 tons, while females reach a significantly smaller 15 tons.

The grey skin is prune-like and rippled, although it sometimes appears brown in the sunlight. The blowhole is placed on the front of the enormous head, slightly to the left, causing the blow to be aimed ahead of the whale. The hump on the back of the Sperm Whale has often been mistaken for a dorsal fin when, in fact, there is no fin. The thick, triangular fluke is elevated high above the water before the whale undertakes a deep dive. This awesome creature can live for up to 70 years.

Sperm Whales have between 20 and 26 pairs of conical teeth on its lower jaw. One tooth measures anything between 80mm and 200mm and can weigh up to 1kg! After years of research, it has been concluded that these teeth are mainly used for fighting, as Sperm Whales feed mainly on squid, for which teeth are not necessary. Scars on bulls confirm this theory.

Female Sperm Whales travel in small groups (known as “pods”) with their young. This species of whale prefers fish and squid to plankton or crustaceans. To hunt this food, they need to embark on the deepest dive of any whale, plunging as low as 2200m.

This beautiful animal is rated as being “Vulnerable” by the IUCN. For many centuries, the Sperm Whale was hunted for its meat, fat and spermaceti. However, it is now protected and enjoys the relative safety of its deep blue home, which is deep enough to be resistant to the harmful impact of pollution. During the period when they were threatened, they had a bad reputation of being violent. However, this came from their determination to defend themselves at all costs, which meant that they often destroyed the whaling boats and could even kill those on them in an attempt to spare their lives.

Spermaceti is a waxy substance that the Sperm Whale uses for buoyancy. It is semi-liquid, has a waxy consistency and is located in the huge head. When preparing for a dive, the whale brings cold water into the spermaceti organ at the front of the head. This water causes the semi-liquid wax to solidify, creating a downward force of up to 40kg. When the time is right, the whale converts stored oxygen to energy, melting the wax and decreasing the downward force, allowing it to rise. This substance was valuable to whalers as it was used for commercial wax-based products (e.g. candles, detergent, vitamins, and other medicines).

The Sperm Whale is found all over the world, including in the Mediterranean Sea. They are generally more common just off continental shelves and canyons.

At birth, the mighty Sperm Whale weighs 1 ton and measures only 4m. Gestation lasts between 14 and 16 months and calves are usually weaned after 2 years. Females only calve once every 5 years, on average. The female whale is social and travels in larger groups (of about 12 other mothers and their calves). Males, on the other hand, leave this group at the age of anywhere between 4 years and 21 years.

The Sperm Whale is not usually the object of whale watching excursions as they are able to stay underwater for such extended periods. Popular spots that yield the best viewing opportunities are Kaikoura on New Zealand's South Island, Andenes and Tromsø in Arctic Norway, the Azores and Dominica, a Caribbean island.