The sperm whale (physeter macrocephalus) is a large toothed whale that is part of the cetacean species, including whale, dolphin, and porpoise.
The sperm whale is the largest of the toothed whales and can grow to be as long as 67 ft. They also have the largest brain out of any animal known to exist.
The name sperm whale comes from the spermaceti organ located in its head. The organ produces a white waxy substance originally mistaken for sperm by early whalers.
While the role spermaceti plays is still not fully understood, in the past, commercial companies used it to make various oils and products such as (transmission fluid, motor oil additives, pharmaceuticals, and detergents) during the whaling era.
Physical Characteristics and Appearance
When fully matured, a male sperm whale will typically grow to be around 50 – 55 ft long and weigh around 35 – 45 tons, with the largest whales measuring in at up to 67 ft. and weighing up to 65 tons.
Female sperm whales, on the other hand, tend to be much smaller, growing to lengths of 34 – 38 ft. long and weighing between 14 – 16 tons.
Compared to other whales, the sperm whale has a unique body and is unlikely to be confused with any other whale species.
It has a block-shaped head that can measure up to 1/3 of the whale’s overall size and length.
The whale’s head contains an organ known as the spermaceti organ, hence its name, which was once believed to produce sperm but has since been proven to serve another unknown use.
Some researchers believe that the spermaceti organ assists the whale with buoyancy by allowing the whale to adjust the fluid balance and consistency within its head.
After all, the sperm whale is the deepest diving animal in the cetacea family.
Others believe the spermaceti organ plays a strong role in assisting the whale with echolocation as the fluids may help the whale absorb acoustic sounds from the echoes it emits.
Compared to the rest of its large block-shaped head, the lower jaw is long, narrow, and filled with cone-shaped teeth that fit into sockets in the upper jaw.
However, the teeth do not appear to be necessary for biting or consuming prey.
This is because sperm whales that have lost their teeth appear to consume their prey with no serious issues compared to toothed sperm whales.
When both the female and male are mature, the male whale usually out measures the female by 30% – 50% in length and weighs significantly more.
In terms of color, sperm whales are usually dark gray color but can occasionally be a light grey or black coloring.
To assist with swimming, sperm whales have small paddle-shaped fins used for steering in eh water and large flukes to propel themselves forward.
Unlike other whale species, sperm whales do not have a dorsal fin but instead have several small humps on their back with one larger hump that may resemble a dorsal fin.
Note: The sperm whale is known to have the largest brain of any known animal currently in existence. They are also known to have the largest eyes of all of the toothed whale species.
Diet and Hunting Methods
A standard diet for sperm whales usually consists of medium to large squid, octopus, and fish.
However, large squid appears to be the most commonly hunted marine animal in their diet.
Due to their deep-diving behavior, it has been difficult to gather information on their particular hunting methods or the exact foods they consume.
Therefore, most of what is known about their diet comes from examining the stomachs and intestines of these marine mammals.
Because the sperm whale hunts for food well below the water’s surface, sperm whales use echolocation for hunting for food and navigating the ocean.
In fact, sperm whales have been recorded searching for foods at depths of up to 3,000 ft.
To obtain enough calories to maintain its energy and blubber supply, an adult sperm whale can eat up to a ton of food per day or about 3% of its body weight.
As stated earlier, the sperm whale’s favorite food is large squid.
While it is difficult to observe their hunting methods, scars found on the sperm whale’s head and the face appears to indicate its attacks on large squid, which try to avoid being consumed by the whale by latching on to the whale’s head.
In addition to hunting large squid, sperm whales are also believed to prey on the megamouth shark.
One study found 3 sperm whales appearing to be attacking a megamouth shark when looking for food.
Sperm whales are known to have 20 – 26 teeth on each side of their lower jaw, with the teeth on the upper jaw rarely breaking through the surface.
The upper jaw’s teeth appear to show no use for hunting or capturing food, while the lower teeth may or may not assist with gripping onto prey.
Even with teeth, sperm whales commonly swallow their food without biting or tearing apart the flesh of their prey, and it is believed that their teeth are not necessary for their survival.
In fact, sperm whales that have completely lost their teeth or have had deformed jaws have been observed as having perfectly normal and unaffected diets despite their circumstances.
One theory as to why sperm whales have teeth but do not use them when hunting for food has to do with their evolutionary process.
As sperm whales evolved, they developed different hunting and survival methods that do not require the use of their teeth, so over the course of millions of years, their teeth have become less developed while other physiological components have continued to develop and thrive on helping these marine mammals survive.
Habitat and Migration
When it comes to habitat, sperm whales can be found swimming through all of the earth’s major oceans.
Unlike other whale species, sperm whales do not appear to stick to a predetermined migration pattern.
Female whales and calves typically remain in tropical climates throughout the year.
In contrast, male whales will make trips to colder temperature higher latitude locations when not mating and back to warmer tropical climates during the mating season.
Although male sperm whales are primarily solitary animals, they may occasionally form loose bonds with other male whales.
Males have been known to wander the oceans throughout their entire lives, and some may even end up traveling the entire world during their 70-year lifespan.
Social Structure and Communication
Adult male whales typically live solitary lives, although they may form loosely connected bonds with other males of the same size and age.
On the other end, females tend to stay in pods of about a dozen or so other whales, usually between 10 – 20 whales.
A pod may consist of young baby whales and other females or 2 – 6 adult males that have formed a temporary bond.
Males whales will stay in their maternal pods until they reach the ages of 5 – 20, at which point they may separate and go off independently.
Vocal communication may involve a series of clicking sounds that are extremely loud and can be heard over great distances.
In fact, the sperm whales clicking sounds are among the loudest known sounds of all animal communication. Unfortunately, not much is known regarding the meaning of these sounds.
Note: Clicking may also assist with echolocation by emitting sounds and determining how long it takes to return to them.
Mating, Reproduction and Lifespan
The gestation period for the sperm whale usually lasts for 14 – 16 months.
Once the child is born, the female sperm will feed its young by producing milk from her mammary glands, which it shoots through the water and into the baby’s mouth.
Unlike other species, baby sperm whales aren’t tied down to feeding strictly from their biological mother and may feed on other females in the group.
Although the female may stop lactating between 1 & 1/2 – 4 years, the baby whale may continue to suckle from its mother’s nipple until 12 years.
However, it is doubtful that the baby whale will continue suckling for that long.
Once sexually mature, these marine mammals may begin mating and reproducing their own offspring.
Female whales typically reach sexual maturity between the ages of 7 – 14, while males usually reach sexual maturity after 18.
A healthy sperm whale can live for more than 70 years in terms of lifespan.
Captivity
Despite huge drops in population due to previous hunting and whaling activities during the whaling era, sperm whales remain fairly numerous today.
However, because of their large size and offshore lifestyle, sperm whales are not held in captivity.
Threats and Predators
In terms of natural threats, sperm whales face occasional attacks from killer whales.
They may also be attacked (less frequently) by false killer whales and pilot whales.
Other threats may include getting tangled in fishing nets/gear, pollution from waste and oil spills, collisions with ships, and global warming.
In the past, the sperm whale was a victim of commercial whaling.
However, they have now been considered a protected species and have recovered some of their losses over the years.
10 Awe-Inspiring Sperm Whale Facts
- Reaching depths of over 9,500 ft., the sperm whale is one of the world’s deepest diving marine mammals.
- Sperm whales are well-known for their diet, consisting of giant squid known for growing to lengths of over 40 ft. long.
- Because the sperm whale often hunts for its food in pitch-black waters, echolocation allows them to maintain complete awareness of their surroundings using sound.
- Some people believe the sperm whale is the only whale with a throat large enough to swallow a human; however, they will likely never run into a person while searching for food due to their deep hunting behaviors.
- Because the sperm whale is a marine mammal, it requires oxygen to breathe. The water that spouts from its blowhole is simply water accumulated around the outside of the blowhole and not water that entered the whale’s lungs.
- The sperm whale’s brain is more than 5 times the weight of a human brain.
- The only known natural predator to the sperm whale is a pack of killer whales. Although these attacks are rare, they have been observed in the wild.
- Sperm whales produce ambergris (whale vomit), which has been used to create perfumes and expensive high-end scents.
- During deep dives, the sperm whale can hold its breath for up to 90 minutes!
- These marine mammals inhale/exhale an average of 3 – 7 times per minute, depending on how active they’ve been.