Though many people might think that humans have the largest brains of any animal, that honor in fact goes to the sperm whale (Phyester macrocephalus). Although the sperm whale does have an 18lb brain, they are not known to be as intelligent as dolphins or primates, but are still capable of solving problems such as stealing meals out of commercial fishing nets. The whale gets its name from the substance contained in its head, known as spermaceti. Scientists believe this substance, which hardens when cold and becomes a liquid when warm, helps the whale with buoyancy and allows it to dive deeper with less effort.
Sperm whales are the largest of all toothed mammals. Bulls can measure up to 67 feet in length, and can weigh over 125,000lbs, with females usually about 50% that size. Sperm whales can be found in every ocean in the world, but seem to prefer ice-free waters over 3,000 feet deep. They are some of the deepest diving mammals in the world and can descend to depths of over 1 mile in search of food, with such dives taking over 1 hour. A carnivore, sperm whales mainly feed on squid, octopuses and various species of fish and sharks. Their large conical teeth are not actually used for hunting, but are rather thought to be a defensive weapon.
These whales live in pods of about a dozen that are segregated by age and sex, with males graduating to smaller and smaller pods as they get older. Males usually live in colder waters closer to the poles, whereas females and their weaning young prefer the more temperate waters near the equator. Sperm whales can live for more than 70 years, and thus breeding is infrequent. Females usually give birth every three to six years, and their calves have been known to suckle for up to 13 years after birth, though this is not common. Females can begin to mate at age seven, with males following about ten years later. Extremely slow-growing, male sperm whales do not reach full size until age 50.
Large and powerful animals, sperm whales have few natural predators. Orcas, also known as “killer whales”, have been known to prey on sperm whale calves and females, but scientists do not believe that any ocean-going creature is capable of preying on the much larger adult bulls. Still, sperm whales do get into fights and several have been spotted with large sucker scars from the giant squid, a 1000lb animal on which the whale frequently feeds.
Historically, the biggest enemy of the sperm whale has been commercial whalers who valued the whale for its blubber and sperm oil to produce myriad of industrial and retail products. It is estimated that over 1 million sperm whales were taken by commercial hunters in the 19thand 20thcenturies. Luckily, commercial hunting of sperm whales has been largely outlawed since 1980 and the current population is estimated to be in the hundreds of thousands.
SPERM WHALE FACTS
- Sperm whales can produce clicking sounds that exceed 230 decibels, the loudest noise produced by any creature on earth.
- The sperm whale population eats over 100 million tons of seafood each year.
- Sperm whales eat up to 2000lbs of food every day.