Name: Sperm Whale (Physeter macrocephalus)
Length: 16-20 metres
Weight: 41,000 kg
Location: Sub-arctic and sub-antarctic waters worldwide
Conservation status: Vulnerable
Diet: Main diet is squid; also consumes fish, octopi, rays, megamouth sharks
Appearance: Long, block-shaped head that can take up to 1/3 of the whale’s body. Grey or black skin.
How do Sperm Whales hunt?
Sperm Whales will usually eat a little over 900 kg of food a day. To find their prey (preferably giant squid) they usually dive somewhere between 300 and 1,200 metres, although they can go as deep as 2 km while on the hunt. An average dive lasts about an hour.
The whales generate the loudest natural animal-based noises in the world – a series of clicks – utilizing echolocation to focus in on their prey.
Sperm Whale’s teeth along its bottom jaw are about 18 to 20 centimetres long, and fit into sockets along the underside of the top of the jaw or palette. The upper teeth never grow out of the upper jaw.
Scientists believe that Sperm Whale’s and giant squid are eternal enemies. While no actual battles have ever been observed, Sperm Whale skin sometimes sport round scars, believed to have come from the suckers of giant squid.
When hunting smaller fish Sperm Whale pods can work together to force feeder fish into bait balls (the smaller fish form a ball-like clump since individuals are more likely to be eaten on their own).
Are Sperm Whales social?
When they’re not breeding, adult male Sperm Whales live on their own, while females and offspring gather into pods of up to 20 members. The males generally leave at around 4 years old, sometimes forming pods of their own with other young adult males. They’ll eventually split off on their own as they get older.
The adult males are the only members of the Sperm Whale family that may venture into the colder waters approaching the North and South Pole. The pods of females and young remain in tropical and temperate zones.
Sperm Whales spend most of their time on the hunt, but will sometimes break off in the afternoon to engage in more social behaviour that includes calling to each other and rubbing against each other’s bodies.
When attacked, the whales form a “marguerite formation,” surrounding a vulnerable pod member, tails outward to ward off harassers.
How fast can Sperm Whales go?
A Sperm Whale’s normal cruising speed ranges somewhere around 5 to 15 km per hour. When they speed up they can swim at approximately 35 to 45 km per hour, maintaining that speed for about an hour.
What are Sperm Whale mating rituals like?
Males reach sexually maturity around 18 years of age, females at 9 years. Males battle for mating rights, then breed with multiple females. They don’t remain to create a harem of females like other animals.
The pregnancy lasts about 15 months, resulting in a single calf. The birth is a social event, with the rest of the pod forming a protective barrier around the birthing mother and calf. The calf may not be weaned for as long as 13 years, although it generally goes off its mother milk at about 2 years. Females will mate once every 4 to 20 years, until they’re about 40 years old.
How long do Sperm Whales live?
Sperm Whales have a life-span similar to humans, living until about 70 years of age. Males will not reach their full size until they’re about 50 years old.
How many Sperm Whales are there today?
The best estimate suggests that there are over 200,000 Sperm Whales alive today.
Do Sperm Whales have any predators?
The Orca or Killer Whale is the biggest threat from the natural world, but Pilot Whales and False Killer Whales have also been known to hunt Sperm Whales. Orcas will go after pods, trying to take a calf or even a female, but the male Sperm Whale is generally too big and aggressive to be hunted.
In terms of human interactions, aside from the usual whale provisions – food, blubber, and oil – Sperm Whales have other materials that were very valuable during the heavy-whaling era:
- Spermaceti – Used in a variety of pharmaceuticals, as well as candles, ointments, cosmetics, and weather proofing.
- Ambergris – A waxy substance formed in the Sperm Whale’s digestive track by irritation from squid beaks, much the same way pearls are formed in oysters. The whale produces it slowly over years to help with the passing of objects (like the squid beaks) that wouldn’t otherwise be broken down in the digestive track. Ambergris was heavily used by the perfume industry, but its rarity eventually led to the search for other substances to take its place.
Do Sperm Whales attack people?
While Sperm Whales will generally retreat from ships, there are incidents in recorded history that suggest that they will attack boats. Some scientists believe that the whales remember past human aggressions and are in fact getting revenge, while others think that the collisions with ships were purely accidental.
8 Special Sperm Whale Facts
- Sperm Whales have the biggest heads in the world.
- They also have the largest brains on Earth (5 times heavier than a human’s).
- “Moby Dick” is based on two real-life sperm whales – one was a whale that rammed and sank the ship Essex, and another actual albino adult male named Mocha Dick.
- Sperm Whales are named after the spermaceti pulled from their bodies, not for… anything else.
- Sperm Whales fertilize the oceans. Their feces float upwards and is dispersed, then consumed by phytoplankton, the bottom of the marine food chain.
- Male adult Sperm Whales have been known to attack Killer Whales to compete for food.
- A Sperm Whale’s heart weighs about the same as two average adult male humans (125 kg).
- The highest sound pressure level ever recorded from an animal was from a Sperm whale off Northern Norway. The single click reached 235 (dB re 1 μ Pa) – above water that corresponds to the sound pressure of the Saturn V rocket at 1 meters distance. This recording proves the hypothesis of “the Big Bang” stating that Sperm whales are able to stun or even kill prey by sound during the hunt.