What kind of whale is a sperm whale? We will explain its characteristics, ecology, and habitat. This whale is distributed all over the world from the North Pole to the Antarctic, and is a member of the whale family that can be seen in any ocean, but despite this, it is designated as an endangered species.
What is a sperm whale? About basic status
Sperm whales are classified into the Spermaceae family and Spermaceae genus. The scientific name is Physeter macrocephalus. It can reach 16-18m in size and weigh up to 50t. A list of basic information is below. In the ocean, some of the giant whales have sharp teeth and specialize in diving. There are many mysteries and research is still needed.
| Japanese（和名） | マッコウクジラ |
| English（英名） | Sperm whale |
| scientific name(学名) | Physeter macrocephalus |
| classification（分類） | Mammalia、Artiodactyla/Cetartiodactyla、 Physeteroidea、Physeter 哺乳綱、偶蹄目、マッコウクジラ科、マッコウクジラ属 |
| IUCN Status(保全状況) | VULNERABLE |
| Length（体長） | 16-18m |
| Weight（体重） | 20-50t |
About classification
Sperm whales belong to the whale family. This species alone constitutes the genus Sperm Whale.
🔬 Biological Classification (Taxonomy)
| 階級 | 分類 |
|---|---|
| 界 | 動物界（Animalia） |
| 門 | 脊索動物門（Chordata） |
| 亜門 | 脊椎動物亜門（Vertebrata） |
| 綱 | 哺乳綱（Mammalia） |
| 目 | クジラ目（Cetacea） |
| 亜目 | ハクジラ亜目（Odontoceti） |
| 上科 | マッコウクジラ上科（Physeteroidea） |
| 科 | マッコウクジラ科（Physeteridae） |
| 属 | マッコウクジラ属（Physeter） |
| 種 | マッコウクジラ（P. macrocephalus） |
About habitat
Sperm whales are distributed throughout the world’s oceans, from the North Pole to the South Pole.
① Global Distribution
Distributed in almost all oceans around the world
Pacific Ocean
Atlantic Ocean
Indian Ocean
Found widely from the equator to the polar regions
👉 This species has one of the widest distributions among whales.
② Characteristics of Commonly Found Oceans
Sperm whales prefer the following locations:
Deep ocean depths of over 1,000 meters
Outside the continental shelf (continental slope)
Areas where the seafloor suddenly deepens
Areas where deep-sea squid are abundant
👉 Oceans with prey (such as giant squid) are important.
③ Latitude Differences (Males and Females)
Habitats differ by sex.
Females and young
Sedentary habitats range from warm to tropical waters
Living in schools (family units)
Mature males
Migratory alone or in small groups
To high latitudes (cold waters)
Also found in the cold waters of the Antarctic and North Pacific Oceans
👉 Males have a wider range of activity.
④ Habitat around Japan
Can also be found in waters near Japan.
Pacific coast (especially areas close to deep waters)
Around the Ogasawara Islands
Off the coast of Boso
Off the coast of Sanriku
Rarely spotted along the Sea of Japan coast
👉 Japan is part of an important migration route.
⑤ Distinguishing between surface and deep sea habitat
Usually rests and breathes at the surface
When feeding, dives to depths of 1,000-2,000m
Dive time: 30 minutes to over an hour
👉 The important thing about habitat is not the surface, but the vertical direction (depth) of the ocean.
feature is? What kind of creature is it?
Sperm whales are basically deep-sea creatures. The fumaroles (breathing holes, nostrils) are concentrated in the front of the head. The tail is triangular and very thick. It is the largest living toothed whale, second only to fin whales and right whales. Its most notable feature is its extremely enlarged head, and it has the largest and heaviest brain of all animals. Therefore, it can be said that it is a whale with very high intelligence. They can spend two-thirds of their lives in the deep sea, diving over 2,000 meters.
① Stunning Appearance
Body Length:
Males: Approximately 15-18m, Females: Approximately 10-12m
Weight:
Males: Over 50 tons
Abnormally Large Head
→ Approximately one-third of the body is head
Square, Sculpted Head
One Blowhole on the Front Left (Very Unique)
👉 At First Sight, It Doesn’t Look Like a Whale
② Enormous Head Interior (Biggest Distinctive Feature)
Their heads contain
Sperm Oil Organs.
Their Functions:
Powerful Echolocation (Sound Detection)
Prey Detection in the Deep Sea
Sound Amplification and Directional Control
👉 Sperm whales
Produce the most powerful sounds on Earth.
③ Deep-Sea Diver
Diving Depth: 1,000-2,000m+
Diving Time: 30 minutes to over an hour
Main Prey:
Giant Squid
Large deep-sea squid and fish
👉 Ability comparable to a human submarine.
④ Diet/Hunting Style
Completely carnivorous
Sharp teeth only in the lower jaw
Searches for prey using sound waves and swallows them nearly whole.
👉 “Catches and swallows” rather than chewing.
What is your personality like?
Sperm whales tend to be solitary or form groups. A large mature sperm whale has many scars on its body surface. This often occurs after males fight over females during the breeding season.
① Generally calm and at their own pace.
They usually swim slowly and quietly.
They are not aggressive toward people or boats.
They do not engage in unnecessary conflicts.
👉 They are like the silent giants of the sea.
② They are highly intelligent and caring towards their companions.
They communicate with each other through clicking sounds.
Females and their young form strong bonds.
They have been reported to protect injured companions and their young.
👉 They have a strong sense of family loyalty.
③ They respond calmly in times of danger.
When threatened,
They form a rosette with their group.
They protect their young in the center.
They do not run around recklessly.
👉 They do not panic.
④ Males tend to be solitary.
Mature males have a lone wolf temperament.
However, they return to their group during breeding season.
They are more solitary than aggressive.
⑤ Their attitude toward humans.
They generally do not attack humans.
They may approach ships out of curiosity.
Even during the whaling era,
they were not indiscriminate attackers.
What is the ecology like?
Sperm whales feed on squid and fish such as giant squid. Female gestation period is at least 12 months. Parenting lasts several years. Sperm whales can live for about 70 to 80 years.
① Deep-sea hunting lifestyle
Mainly lives in the deep sea, at depths of 1,000-2,000m
Prey:
Giant squid
Large deep-sea squid
Deep-sea fish
Searches for prey using echolocation
👉 Hunters rely more on sound than sight.
② Exceptional diving ability
Dive time: 30 minutes to over an hour
Dive depths: Recorded depths of over 2,000m
Dive → hunt → surface to rest, repeating the cycle
👉 One of the strongest diving abilities among mammals.
③ Group structure (varying by sex)
Females and young
Family groups of 10-20 individuals
Cooperative parenting (parenting behavior)
Typically spend their entire lives in warm waters
Mature males
Generally solitary
Long-distance migrations to high latitudes (cold waters)
Join groups only during breeding season
👉 Clear social structure.
④ Daily rhythm
Breathing and resting at the surface
Diving deep to feed
Resting again at the surface
This cycle is repeated multiple times per day.
⑤ Breeding and rearing
Gestation period: Approximately 15-16 months
Birth: One young
Lactation period: Several years
Young young are protected by their mother and the group for long periods of time.
👉 Growth is very slow.
⑥ Lifespan and Growth
Lifespan: 60–70 years (possibly longer)
Takes more than 10 years to reach maturity
Long-lived, slow generational succession
👉 Ecology that makes it difficult for populations to recover.
Are there any natural enemies?
Natural enemies are killer whales and sharks. Others include humans.
About Sperm Whale Calves
Sperm whale calves are “cuddly, intelligent baby whales that grow up protected by their mothers and pods for a very long time.”
In contrast to the gigantic adult whales, they go through a social and sensitive developmental stage.
① Immediately after birth
Body length: Approximately 3.5-4m
Weight: Approximately 1 ton
Able to swim immediately after birth (unusual among mammals)
Swim alongside or under their mother’s belly
👉 Babies are already much larger than humans.
② Nursing and Growth
Breast milk is very high in fat.
Lactation period: More than 2 years (sometimes several years).
Growth is slow but steady.
👉 Extended lactation develops the brain and diving ability.
③ Raising in a group
Live in a family group centered around a female and her young
Females other than the mother
Take turns watching over the young (nurturing behavior)
In times of danger, they focus on protecting the young
👉 “Cooperative parenting” in the sea.
④ Behavioral Characteristics
Often play near the surface
Practice swimming and diving through play
Learn communication by making clicking sounds
👉 Play = learning.
⑤ Development of diving ability
Young animals start with shallow dives
Gradually develop deeper and longer dives
It takes more than 10 years to reach adult level
👉 A long training period before becoming a deep-sea hunter.
⑥ Danger and Protection
Young animals’ natural predator: Killer whales
They form a circle with their young, protecting them in the center
Getting lost reduces their survival rate
⑦ After adulthood
Females: Often remain in the group for their entire lives
Males: Leave the group at around 10-15 years of age and become independent
It takes more than 20 years to become a mature male
Is the sperm whale an endangered species?
Sperm whales are listed as an endangered species. It is also listed in Appendix I of the Washington Convention, and international trade is restricted. The reason for the large decline in population is probably the whaling problem and ocean pollution. Although they are now restricted to some extent, in the past they could do whatever they wanted, so their numbers have decreased dramatically.
✅ IUCN (International Union for Conservation of Nature) Red List
Category: Vulnerable (Vulnerable/Endangered)
→ This species is considered to be at high risk of future extinction (a level less than endangered).
👉 IUCN is the world’s most authoritative species assessment organization, and sperm whales are classified as “vulnerable.”
🐋 Other conservation assessments
Under U.S. law (the Endangered Species Act), sperm whales are classified as “endangered.”
They are also listed in the Convention on International Trade in Endangered Species (CITES),
which strictly restricts international trade.
Major reasons
Former large-scale whaling
During a long history of mass hunting by humans, populations have declined.
Fishery entanglement/accidents
Fish can die from entanglement in nets or collisions with ships.
Marine pollution/noise
Chemical pollution and ship noise are thought to affect even deep-sea species.
🐋 What about the population?
The exact global population is unknown, but some estimates put it at hundreds of thousands to millions (high compared to other whales).
However, because they mature and reproduce slowly, their populations are small.
Can sperm whales be kept as pets?
Sperm whales cannot be kept in captivity. In the first place, it is not an animal that can be kept as it is too large.
① Completely illegal
Sperm whales are internationally protected (IWC, CITES)
Private captivity, ownership, and trade are prohibited in almost all countries, including Japan.
Capturing and transporting them is illegal.
👉 Buying or keeping them is not an option.
② Ecologically impossible to keep.
Sperm whales are:
15-18m in length and weigh over 50 tons.
Deep-sea creatures that dive to depths of 1,000-2,000m.
Migratory animals that travel dozens of kilometers per day.
👉
❌ Aquarium tanks.
❌ Ocean fish ponds.
❌ Private swimming pools.
None of these environments are viable.
③ Extremely advanced intelligence and sociality.
Highly intelligent.
They communicate through sound and live in family groups.
Long-term care and training are required.
👉 Keeping them alone or in an artificial environment can cause severe psychological distress (an animal welfare issue).
④ Safety Danger
A single flick of their tail fin is enough to destroy a ship.
The risk of unintended accidents is extremely high.
Friendliness does not necessarily mean safety.
👉 Even “gentle” giant animals are uncontrollable.
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