What kind of whale is a right whale? We will explain its characteristics, ecology, and habitat. Right whales are characterized by their large heads, which are about one-third of their body length, among the large whales. We will explain about this whale, which lives in warm areas along the Atlantic and Pacific coasts.
What is a Right Whale? Basic Stats
The right whale is a species of baleen whale belonging to the family Right Cetacea and the genus Right whale. Its scientific name is Eubalaena japonica, its kanji characters are Sebi-kujira and Seibi-kujira, and its English name is North Pacific Right Whale. Its total length is 15-17m and its weight is 45-60t. The list of information is as follows. It is a species with a very large head, and species such as the Southern Right Whale and the North Atlantic Right Whale belong to the Right Whale genus.
| Japanese（和名） | セミクジラ |
| English（英名） | North Pacific Right Whale |
| scientific name(学名) | Eubalaena japonica |
| classification（分類） | Mammalia、Artiodactyl、 Balaenidae、Eubalaena 哺乳綱、鯨偶蹄目、セミクジラ科、セミクジラ属 |
| IUCN Status(保全状況) | VULNERABLE |
| Length（体長） | 15-17m |
| Weight（体重） | 45-60t |
Taxonomic position (taxonomy)
| 階級 | 分類 |
|---|---|
| ドメイン | 真核生物 (Eukaryota) |
| 界 | 動物界 (Animalia) |
| 門 | 脊索動物門 (Chordata) |
| 綱 | 哺乳綱 (Mammalia) |
| 目 | 鯨偶蹄目 (Cetartiodactyla) |
| 亜目 | 鯨類亜目 (Cetacea) |
| 科 | ヒゲクジラ科 (Balaenopteridae) |
| 属 | メガプテラ属 (Megaptera) |
| 種 | Megaptera novaeangliae |
Habitat
Right whales inhabit the temperate zones of the North Pacific and North Atlantic, as well as the coasts of the subarctic zones of the Southern Hemisphere. Despite their long history, there are many mysteries surrounding them. For this reason, scientific research on them is being conducted internationally.
- Geographic Distribution
Distributed throughout the world in temperate, tropical, and polar waters.
Breeding and Calving Grounds: Warm coastal waters and around archipelagos.
Southern Hemisphere: East coast of Australia, New Zealand, and coastal South America.
Northern Hemisphere: Hawaii, west coast of Mexico, etc.
Feeding Grounds: Cold waters, nutrient-rich coasts, and continental shelves.
Southern Hemisphere: Cold waters around Antarctica.
Northern Hemisphere: Alaska, east coast of Canada, etc.
- Habitat Characteristics
Uses both coastal and offshore areas.
Breeding season: Shallow waters and around archipelagos, ensuring the safety of calves.
Feeding season: Cold offshore waters rich in plankton and small fish.
Seasonal Large-scale Migration (Migration).
Winter: Birthing and breeding in warm coastal waters.
Summer: Feeding in cold waters at high latitudes.
- Migration/Migration
Typical long-distance migration
Migrates thousands to 10,000 kilometers in both the Northern and Southern Hemispheres
Seasonally travel between breeding and feeding grounds
They travel alone or in small groups during migration, but form schools in wintering areas
- Importance of habitat conditions
Abundant food (small fish and plankton) is key to survival
Water temperature and safety in shallow waters are essential for breeding and rearing
Sensitive to changes in the marine environment (global warming, fishing activity)
What are its characteristics? What kind of creature is it?
Right whales have a large head that takes up about a quarter of their total length. They are a unique species of whale because they have long baleen that can be over 2 meters long, they do not have a dorsal fin, and each individual has a different shape. There are scab-like raised layers of stratum corneum on the upper and lower jaws. They have two blowholes, one on each side.
- Physical Size and Appearance
Large Baleen Whale
Body Length: 12–16 m for both adult males and females
Weight: Approximately 25–30 tons
Very long pectoral fins
Equivalent to approximately 1/4 of body length
Used for maneuvering in the water and for intimidation and courtship displays
Hump on back
Name: “Humpback”
Body Color
Back: Black to dark gray
Belly: White
The undersides of the pectoral and caudal fins are black and white, used for individual identification
- Head and Mouth
Prominent hump-like protrusion on head (small protuberance in front of the head)
Baleen plates (unique to baleen whales) on the upper jaw, allowing them to filter plankton and small fish for feeding
Beak: Relatively short and rounded
- Behavior and Ecology
Feeding Behavior
Feeds on small fish, krill, and plankton
Unique “bubble-net feeding”
Creates a circular bubble curtain underwater, trapping schools of fish and efficiently feeding
Swimming Technique
Powerful, stable swimming adapted to long-distance migration
Extensive pectoral fin movements allow for underwater direction changes
Swimming Performance
Displayed spectacular behaviors, including breaching and slapping
Methods of courtship, territorialization, and communication
- Calls
Low- to mid-frequency songs
Sings, especially by males, during the breeding season to attract females and mark their territory
Repeated patterns lasting several minutes to several tens of minutes
- Special Characteristics
Unusually long pectoral fins, measuring 1/4 of the body length
The hump on the back and the pattern on the underside of the tail fin can be used for individual identification
Adapted for long-distance migration (between breeding grounds and feeding grounds)
Capable of cooperative behaviors, including bubble-net feeding
What is their personality like?
Right whales are said to have a gentle and friendly nature, and are said to be easy for humans to handle. They are also very curious, and will play with humans. They are sometimes called “the kindest creature on Earth.”
- Sociality
Generally calm and non-aggressive.
Adults often act alone or in small groups (mothers and offspring or companions).
In wintering areas, they form groups of several individuals.
They communicate with each other through vocalizations (singing) and tail slapping.
- Interpersonal and Other Organisms
They are relatively timid around humans, but some individuals show curiosity.
They may swim slowly around ships and tourist boats, but will keep their distance if approached.
They have few predators, so they rarely engage in defensive behavior.
- Foraging and Play Behavior
They are cooperative and planned while foraging.
“Bubble net feeding” is performed cooperatively by multiple individuals.
Jumping (breaching) and tail slapping (slapping) are used for play, communication, and courtship.
They are active and highly athletic, and can withstand long-distance migrations.
What is their ecology like?
Right whales are small in population, and most of their ecology, such as their distribution, has not been clarified. They give birth in winter and spring, and their breeding grounds are thought to be in tropical or subtropical regions.
- Habitat and Migration
Breeding and birthing in warm coastal waters
Hawaii, the west coast of Mexico, the coast of Australia, New Zealand, etc.
Feeding in cold, nutrient-rich waters
Antarctic regions, Alaska, the east coast of Canada, etc.
Long-distance migration
Travels thousands to 10,000 kilometers between breeding and feeding grounds
Migratory behavior occurs alone or in small groups
- Feeding Behavior
Omnivorous, but primarily feeds on small fish, krill, and plankton
Unique bubble-net feeding
Creates a circular bubble curtain underwater to trap schools of fish and efficiently feed
Highly cooperative behavior involving cooperation with other fish
Feeding occurs primarily in high-latitude waters during the summer
- Reproduction and Rearing
They live in warm coastal areas during the breeding season.
Gestation Period: Approximately 11–12 months
Birth: One calf (occasionally twins)
Calfs stay closely attached to their mothers.
They feed exclusively on breast milk for several months.
The mother-calf bond is strong, and the mother protects the calf’s safety.
- Sociality and Behavior
During the breeding season, males sing to court and mark their territory.
Frequent breaching (jumping) and tail flicking are playful behaviors.
This behavior has multiple functions, including communication, territoriality, and courtship.
They are highly cooperative, and have developed group feeding and social behaviors.
Do they have any natural enemies?
Their natural enemies are killer whales and sharks. Other than that, there are humans.
About Baby Right Whales
This article provides detailed information about baby right whales (Megaptera novaeangliae).
- Birth and Early Life
Birthing Location: Warm coastal areas and archipelagic areas (Hawaii, Mexico, Western Australia, etc.)
Birthing Season: Winter (breeding season)
Litter Size: Generally one (twins are rare)
Body Length: Approximately 4–5 m at birth
Weight: Approximately 1 ton at birth
- Appearance
Dorsal and pectoral fins are not yet as developed as in adults
Body color is dark gray to black with a white belly, and the patterning on the tail and pectoral fins is immature
The body surface is smooth, and as they grow, the pectoral fins become longer and a dorsal hump appears
- Feeding and Breastfeeding
Breastfeeding
Breast milk is high in fat, resulting in rapid weight gain
Feeding behavior is learned through observation and imitation of the mother
Exclusively dependent on breast milk for the first few months
Lactation Period: Approximately 6–12 months
The mother protects the young and teaches them how to swim and breathe
- Behavior and Sociality
Cubs spend time closely with their mothers.
They acquire strength and swimming skills through play.
Early breaching and tail slapping behaviors are observed.
They may interact with other mother-calf groups, contributing to the development of social skills.
- Growth and Independence
They grow to a body length of 8–10 m in their first year.
Their pectoral fins gradually lengthen, and their tail and dorsal ridges also develop.
They become independent and capable of feeding around 1–2 years of age.
They migrate following their mothers, gradually becoming more independent.
Are right whales an endangered species?
Right whales are registered and designated as an endangered species. The current population and past distribution are unknown, and there are many mysteries. In addition, due to the small original population, overfishing is a problem. They were caught in the North Pacific Ocean in small quantities until the 1960s, but commercial whaling has now been completely stopped. They need to be protected.
- IUCN Red List Classification
Classification: Endangered (EN)
Reason:
Populations have declined significantly due to past commercial whaling.
Changes in migration and breeding habitats.
- Population and Distribution Status
The total global population is estimated to be approximately 80,000.
Population sizes differ between the Northern and Southern Hemisphere stocks.
The Southern Hemisphere (Antarctic Ocean) population is showing signs of recovery.
The North Pacific and North Atlantic populations are still recovering.
Distribution: Temperate and tropical waters worldwide (breeding areas: warm coasts, feeding areas: cold waters).
- Major Threats
Historical Impacts of Commercial Whaling
Large-scale whaling continued until the mid-20th century, resulting in a dramatic decline in populations
Collisions with Ships
Castles and Injuries Due to Collisions in Coastal Waters Near Shipping Routes
Competition with Fisheries and Entanglements
Castles can die from entanglement in nets and fishing gear
Environmental and Climate Change
Changes in Water Temperature and Plankton Levels in Feeding and Breeding Grounds
Can right whales be kept as pets?
Right whales cannot be kept as pets. To begin with, they are too large to be kept as pets. Images and photos can be viewed on the Internet. They are sometimes sold as figurines at aquariums.
- Legal and Conservation Reasons
Endangered species (IUCN: EN, CITES Appendix I)
International trade and capture are prohibited
Private captivity is illegal
Captivity and captivity of wild individuals are not permitted in Japan or other countries.
Captivity is impossible except for conservation purposes (zoos and research facilities).
- Physical and Ecological Reasons
Giant Size
Adult: 12–16 m in length, 25–30 tons in weight
It is practically impossible to keep them in aquariums or pools.
Long-distance migration habits like migratory birds.
Move thousands to 10,000 km annually between breeding grounds and feeding grounds.
Life cycle cannot be reproduced in captivity.
Unique Feeding Behavior
Consume large amounts of plankton and small fish.
Cooperative feeding behavior, such as bubble-net feeding, is essential.
- Examples in captivity
Cannot be exhibited in aquariums
Due to their large size, they have never been kept in captivity
Research and observation are conducted through tagging and tracking of wild individuals
Reproducing artificial breeding and feeding habits in captivity is nearly impossible
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