Liptodes vexillifer

Last updated: March 29, 2023
Verified by: AZ Animals Staff
© Institute of Hydrobiology, Chinese Academy of Sciences / public domain, Wikimedia Commons – License / Original

Baijis use echolocation to find food in the Yangtze River.


Baiji Scientific Classification

Scientific Name
Liptodes vexillifer

Read our Complete Guide to Classification of Animals.

Baiji Conservation Status

Baiji Locations

Baiji Facts

Yellow catfish, carp, copper fish
Group Behavior
  • School
Fun Fact
Baijis use echolocation to find food in the Yangtze River.
Estimated Population Size
Biggest Threat
Commercial fishing nets, habitat loss
Most Distinctive Feature
A long, upturned nose
Other Name(s)
Yangtze dolphin, white fin, white flag

Baiji Physical Characteristics

  • Grey
  • Blue
  • White
Skin Type
Top Speed
37 mph
24 years
368 lbs
7.5-8.5 feet

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The baiji is sometimes called the Yangtze dolphin, the White fin, or the White flag.

The baiji is an animal that lives in the Yangtze River in China. There are believed to be very few baijis left in existence. Its official conservation status is Critically Endangered, but some scientists believe they are extinct as there have been no confirmed sightings of this mammal since before 2006, although some have thought to have seen this river dolphin as recently as 2016.

3 Incredible Baiji Facts!

• Swallowing prey: The baiji has 30 to 36 sharp teeth. But, instead of chewing small fish and other prey, they swallow them whole.
• Echolocation: This mammal has very poor vision. It uses echolocation or sound waves to find schools of fish and other prey.
• Dolphin in jeopardy: This mammal is Critically Endangered and possibly extinct. For decades, it was unintentionally caught in commercial fishing nets. When these mammals are caught in fishing nets they cannot come up for air.

Evolution And Origin

The Baiji dolphin is the only ancient member of the Lipotidae family and has lived in the Yangtze river for about 20 million years, at the time of the Miocene era. Unfortunately, as a result of human activity, this once long-established resident is now most likely extinct, pronounced so in 2007, as there have been no sightings of them in the river since 2006. The Lipotidae family was an ancient species that separated from other river dolphins during the evolutionary process over 20 million years ago.

Classification And Scientific Name

The scientific name of the baiji is Lipotes vexillifer. Lipotes is Latin meaning left behind, and vexillifer is a Latin word meaning flag bearer.

The baiji is also known as the Yangtze dolphin, the white fin, or the white flag. It’s the only member of the lipotidae family and is in the Mammalia class.

Baiji is one of six species known as river dolphins. The others include:

• Ganges River dolphin
Amazon River dolphin
• Araguaian River dolphin
• Bolivian River dolphin
• La Plata River dolphin

The baiji is Critically Endangered. Scientists disagree on how many are left in existence. Some scientists believe there may be 10 or fewer while other scientists believe them to be extinct.


Most of these mammals live in the open ocean. But the baiji or White fin is known as a river dolphin due to its specific habitat. Other notable examples include:

• Bolivian River dolphin: This freshwater river dolphin is a little bigger than the baiji. Bolivian River dolphins can grow as long as 9ft and weigh just under 400 lbs. Their existence is also under threat due to commercial fishing activity in the Bolivian River.
La Plata dolphin: This species lives in freshwater as well as saltwater estuaries. It’s smaller than the baiji. The La Plata dolphin grows to be 5.9ft. long and weighs 110 lbs at the most.
• Ganges River dolphin: This freshwater dolphin’s behavior is similar to the baiji in that it hunts prey by echolocation. But the estimated population of this dolphin ranges between 1,200-1,800.


A baiji is an animal with a bluish-gray back and a white underside. They have 30 to 36 sharp teeth on their upper and lower jaws. A baiji has one stomach that’s divided into three chambers whereas most dolphins have two stomachs. Their nose is long and beaklike. They have rounded fins that allow them to move swiftly through river water. Baijis range in length from 7.5 to 8.5 feet. They weigh around 360 pounds.

Their coloration allows them to blend in with their river habitat. The ability to swim very fast is another defensive feature of this dolphin. The fastest a baiji can swim is 37mph.

Distribution, Population, And Habitat

The baiji lives in the Yangtze River in China. They are freshwater dolphins. Their hunting behavior includes finding prey on both the floor of the river as well as in shallow areas. The estimated population is anywhere from 10 of these dolphins to none. This is why their official conservation status is Critically Endangered. Some scientists believe they are an extinct species.

This mammal is critically endangered for a few reasons. For decades, these dolphins were (unintentionally) captured in the nets of commercial fishermen and died. Also, water pollution from growing industries and deforestation in China has severely threatened the habitat of this dolphin. As this mammal used echolocation, the increase in noise pollution and river congestion harmed their ability to safely traverse the waterway. The construction of the Three Gorges Dam additionally caused their spawning ground to be harmed, as a result of the drop in water levels and temperatures.

Today, laws have been put in place to protect any remaining baiji dolphins in the Yangtze River. The same laws that protect the baiji also cover another threatened species known as the Yangtze finless porpoise.

Predators And Prey

Baiji in the water Attribution not found

The baiji is believed to be extinct as a result of human activity.

©Institute of Hydrobiology, Chinese Academy of Sciences / public domain, Wikimedia Commons – License

Humans are the only predators of baiji dolphins though they are not eaten by people.

The diet of a baiji dolphin consists of small fish such as carp, yellow catfish, and copper fish. These fast dolphins are able to capture small fish and swallow them whole.

The conservation status of baijis is Critically Endangered.

Reproduction And Lifespan

Baiji in the water

Calves will stay with their mothers for 3 to 6 years before becoming independent.

©Roland Seitre / CC BY-SA 3.0, Wikimedia Commons – License

Breeding season is in the spring and summer for the baiji dolphin. Though not much is known about their mating rituals, scientists know the gestation period of a female range from 6 to 12 months. She gives live birth to 1 baby also known as a calf.

The mother dolphin nurses her calf and teaches it how to swim as well as how to rise to the surface for air. A calf may nurse until the age of 18 months old. At that time, the mother dolphin begins to teach her calf how to hunt for small fish. A calf may stay with its mother for 3 to 6 years before becoming independent.

Male baijis become sexually mature at 6 years of age while females are sexually mature at 4 years old. One of the most interesting facts about this mammal is they can live to be 24 years old.

In Fishing and Cooking

It’s true that dolphin meat is a delicacy in some countries such as Japan. But baijis are not plentiful enough for humans to hunt and eat. Plus, they are now protected by law.

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About the Author

Melissa Bauernfeind was born in NYC and got her degree in Journalism from Boston University. She lived in San Diego for 10 years and is now back in NYC. She loves adventure and traveling the world with her husband but always misses her favorite little man, "P", half Chihuahua/half Jack Russell, all trouble. She got dive-certified so she could dive with the Great White Sharks someday and is hoping to swim with the Orcas as well.

Baiji FAQs (Frequently Asked Questions) 

Where are baiji found?

Baijis live in the Yangtze River in China.

How big do bajis get?

They can grow to be 7.5 to 8.5 feet long and weigh around 360 pounds.

What do baijis eat?

The diet of this mammal includes small fish such as yellow catfish, carp, and copper fish.

Where do baijis live?

They live in a freshwater river habitat.

Is the baiji extinct?

Officially, baiji (scientific name: Liptodes vexillifer) are listed as Critically Endangered. There have been some unconfirmed sightings of these dolphins in the Yangtze River. But some scientists believe they are now extinct.

How many baiji are left in the world?

There is a debate as to exactly how many baiji are left in the world. Some groups of scientists say that there are 10 or fewer of them left. Other scientists believe there are none. However, there are a couple of facts to take into consideration.

One is that baiji dolphins have elusive behavior. Secondly, the Yangtze is the longest river in Asia. This means these mammals have a lot of space to travel in their habitat.

So, just because no one has seen any baijis in a few years doesn’t mean they won’t reappear one day.

What Kingdom do Baijis belong to?

Baijis belong to the Kingdom Animalia.

How do Baijis have babies?

Baijis give birth to live young.

Thank you for reading! Have some feedback for us? Contact the AZ Animals editorial team.

  1. BioExpedition, Available here:
  2. Yangtze River Cruise, Available here:
  3. Animal Diversity Web, Available here:

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