What fills a sperm whale's huge head, and why do scientists still wonder about it? The sperm whale is the largest of the toothed whales. Here is how big it is, how it finds food deep down and how its family lives.
An adult male sperm whale is 49 to 59 feet (15 to 18 metres) long and can weigh up to 45 tons. An adult female is smaller, up to about 40 feet long. Both are dark gray.
A sperm whale's head is about one-third of the length of its whole body. The sperm whale has the largest brain of any animal.
The sperm whale has one blowhole, on the left side of its head. Its spout, or blow, points forward instead of straight up.
A sperm whale eats mostly squid, and it eats about one ton of food in a day. Its large teeth are in its lower jaw, and they are 3 to 8 inches long.
Sperm whales dive deep down in the ocean to find food. They often dive down to about 2,000 feet (600 metres). A sperm whale can dive deeper than 3,000 feet (about 1,000 metres), and it can stay underwater for an hour or more.
Sperm whales make clicking sounds, and they use echolocation to find food.
Adult male sperm whales usually live alone, except in the breeding season. Young males leave their family groups and live with other young males. Female sperm whales and their young travel together in groups, and they stay in warm tropical waters all year.
A mother sperm whale carries her calf for 14 to 16 months before it is born. A newborn calf weighs about 1 ton and is about 13 feet long. The calf nurses for two years or more.
Now back to that big head. It holds a waxy substance called spermaceti, and the sperm whale is named after it. A sperm whale's head can hold about 4 tons of spermaceti. Scientists are still not sure what the spermaceti is for.
Words to know
- spermaceti: waxy substance
- echolocation: finding by sound
- blowhole: a whale's nose
- tropical: very warm
- calf: baby whale
