Animal
Gray whale
The gray whale is a big whale with spotty gray skin. Every year it swims a very long way, from icy seas to shallow lagoons and back.
The gray whale is a baleen whale of the North Pacific Ocean. It sucks up mud from the seafloor to catch tiny animals, and it makes one of the longest yearly journeys of any mammal: about 16,000 kilometers there and back between Arctic feeding seas and shallow lagoons in Mexico.
Eschrichtius robustus is a bottom-feeding baleen whale of the family Eschrichtiidae whose two surviving populations live in the North Pacific. The eastern population recovered from whaling and was delisted in 1994, but has swung widely since 2016; the western population numbers fewer than 300 and remains endangered.
Photo: Carlos Valenzuela, CC BY-SA 4.0, via Wikimedia Commons
Meet the gray whale
The gray whale is a very big whale.
Its skin is gray with pale spots. It has bumps on its back instead of a fin. Little animals called barnacles live on its skin!
The gray whale can grow to about 15 meters long, longer than a school bus, and weigh about 41,000 kilograms. Females are a little bigger than males. Its skin is gray, covered in pale patches, and often crusted with barnacles and tiny animals called whale lice. One whale can carry more than 180 kilograms of them!
Instead of a fin on its back, a gray whale has a low hump followed by a row of small bumps called 'knuckles'. Long ago, whalers nicknamed gray whales 'devil fish' because they fought back so hard when hunted.
Eschrichtius robustus reaches about 49 feet (15 meters) and 90,000 pounds (about 41 tonnes), females being slightly larger. The mottled gray body carries barnacles and cyamid amphipods (whale lice), most densely on the head and tail. Small eyes sit just above the corners of the mouth, and the pectoral flippers are broad, paddle-shaped and pointed.
There is no dorsal fin: a dorsal hump about two-thirds of the way back is followed by 6 to 12 small 'knuckles' leading to flukes nearly 3 meters wide, with S-shaped trailing edges and a deep central notch. It belongs to the family Eschrichtiidae. Whalers called it 'devil fish' for its aggressive reactions when harpooned.
Quick facts
- Group
- Mammal
- Length
- up to 15 m
- Weight
- up to 41,000 kg
Where it lives and travels
Gray whales live in the Pacific Ocean.
In summer they eat in cold seas near Alaska. In winter they swim far south to shallow lagoons in Mexico. Many babies are born there.
Gray whales once lived across the north of the world, but today they are only regularly found in the North Pacific Ocean, mostly in shallow water near the coast. There are two groups: one along the west coast of North America and a much smaller one along the coast of eastern Asia.
Most of the North American gray whales spend summer feeding in the Bering and Chukchi seas near Alaska. In fall they swim south along the coast to spend winter in the shallow lagoons and bays of Baja California, Mexico. In spring they swim north again.
Once found throughout the Northern Hemisphere, including the North Atlantic, gray whales now occur regularly only in the North Pacific, mainly in shallow coastal waters. The eastern North Pacific population ranges along western North America; the western North Pacific population lives mainly along eastern Asia, feeding off Sakhalin Island and southeastern Kamchatka.
Most eastern whales feed in summer in the northern Bering and Chukchi seas, though some stay along the coast from Southeast Alaska to northern California. In fall they migrate south to wintering and calving lagoons in Baja California, then travel north from mid-February to May. NOAA Fisheries reports a round trip of about 10,000 miles (16,000 kilometers), sometimes more than 14,000 miles, and tagging and photo-ID show some western whales also migrate to the North American coast.
Its habitat
Where can you find this animal?
- Migration route · Countries and seas named by a scientific source
- Lives here naturally · Countries and seas named by a scientific source
- Sightings recorded · Records of wild sightings (GBIF)
Migration route · Countries and seas named by a scientific source
The eastern North Pacific migration: most gray whales feed in summer in the northern Bering and Chukchi seas and swim south along the coast of North America to winter lagoons in Baja California, Mexico, about 16,000 km there and back. The line follows the coast in a simplified way; it is not the exact path of any whale.
Places: Pacific Ocean and Arctic Ocean.
Source: https://www.fisheries.noaa.gov/species/gray-whale · checked October 2026
Lives here naturally · Countries and seas named by a scientific source
Mostly shallow coastal waters of the North Pacific, from the Arctic feeding seas off Alaska and Russia to winter lagoons in Baja California, Mexico, plus a small western group along eastern Asia. Gray whales live in the sea, not inland.
Places: Pacific Ocean, Arctic Ocean, United States, Canada, Mexico, Russia and Japan.
Source: iucn-red-list · checked October 2026
Sightings recorded · Records of wild sightings (GBIF)
Counts of GBIF records of wild observations (human and machine) and preserved specimens. Records include introduced populations, vagrants, escaped or released animals and misidentifications, so a country with records is not necessarily part of the native range.
Wild sightings have been recorded in United States, Mexico, Canada, Russia, Japan, Netherlands, South Korea, France and 17 more places.
Source: gbif · checked October 2026
Range maps show where scientists say an animal lives, often country by country. An animal may live in only part of a country shown, and sightings records can include animals that wandered far from home.
Mud-slurping feeders
Gray whales eat tiny animals that live in the mud.
They roll on their sides and suck up mud from the seafloor. Then they push out the mud and keep the food.
Gray whales are bottom feeders. They swim slowly along the seafloor, rolling onto one side, and suck up mouthfuls of mud and water. Then they push it all out through the baleen in their mouths, which works like a sieve, keeping tiny shrimp-like animals called amphipods and other small creatures.
They leave long trails of mud behind them and pits in the seafloor. Most gray whales spend the summer feeding in the cold northern seas.
Gray whales are primarily benthic and epibenthic feeders, taking a wide range of invertebrates such as amphipods that live in and just above the seafloor. Rolling onto their sides and swimming slowly, they suck sediment and prey into the mouth and filter it through 130 to 180 short, coarse baleen plates on each side of the upper jaw.
This feeding often leaves long trails of mud behind them and 'feeding pits' on the bottom. Most eastern whales spend the summer feeding in the northern Bering and Chukchi seas. NOAA Fisheries reports that some recently stranded whales were skinny or emaciated, suggesting they were not finding enough food, and warns that changing sea-ice timing and distribution in the Arctic could change where their prey is found.
Did you know?
Gray whales swim very, very far every year.
A gray whale's yearly round trip is about 16,000 kilometers, and some swim more than 22,000.
NOAA Fisheries gives a round trip of about 10,000 miles, in some cases upwards of 14,000, one of the longest annual migrations of any mammal.
Barnacles, knuckles and baleen
Gray whales carry passengers! Barnacles and whale lice live on their skin.
Gray whales have no teeth. They have baleen, which works like a big comb.
A gray whale's skin is a home for other animals. Barnacles stick to it, and tiny whale lice crawl among them, especially on the head and tail. They make the whale look patchy and crusty.
Gray whales have no teeth. Instead, 130 to 180 baleen plates hang from each side of the upper jaw. Gray whale baleen is coarse, and it strains food out of mud. Babies are born dark gray and turn lighter as they grow older.
The gray whale's external fauna, barnacles and cyamids, concentrates on the head and tail. All individuals are mottled with lighter patches, and the Monterey Bay Aquarium explains that white patches mark spots where barnacles and whale lice have attached. Calves are born dark gray and lighten with age to brownish or light gray.
The filtering apparatus consists of 130 to 180 coarse baleen plates per side, suited to separating prey from sediment. The broad, pointed flippers, dorsal hump, 6 to 12 knuckles and wide notched flukes complete the profile. Small eyes sit just above the corners of the mouth.
Growing up
A gray whale mom has one baby at a time.
The baby is born in winter, in shallow water near Mexico. Then it swims north with its mom.
A gray whale mother is pregnant for 12 to 13 months. Her calf is born in winter, between early January and mid-February, during the migration or in the shallow lagoons and bays of Mexico. A newborn is already about 4.3 to 4.9 meters long and weighs about 900 kilograms.
In spring, the calf swims north beside its mother to the feeding seas. Gray whales are grown up and can have calves of their own at 6 to 12 years old, usually at about 8 or 9.
Gestation lasts 12 to 13 months and produces a single calf, born from early January to mid-February during migration or in Mexican lagoons and bays. Newborns are about 14 to 16 feet (4.3 to 4.9 meters) long and about 2,000 pounds (roughly 900 kilograms).
Sexual maturity comes at 6 to 12 years, averaging 8 to 9. Lifespan is not known: one female was estimated at 75 to 80 years old after death. Calf counts have stayed low in recent years: NOAA estimated only 85 calves in 2025, the lowest on record. A calf drinks about 190 liters of milk a day before its first trip north.
Travelers and boat-watchers
Gray whales often swim alone or in small groups.
In some places, gray whales are curious about boats! Lots of people go whale watching to see them.
Gray whales often travel alone or in small groups that change a lot. Big gatherings can form in their feeding and breeding areas.
In some places, gray whales are curious about boats. That makes them a favorite of whale watchers from Canada to Mexico. Killer whales hunt gray whales. Whale watchers are asked to stay at least 100 yards away so the whales are not disturbed.
Gray whales are frequently seen alone or in small, mostly unstable groups, though large aggregations form on feeding and breeding grounds; as in other baleen whales, long-term bonds between individuals are thought to be rare. Killer whales prey on them.
Their coastal migration and curiosity toward boats in some locations have made them the focus of whale watching from British Columbia to the Baja California lagoons. NOAA Fisheries notes this can disturb the whales and recommends keeping at least 100 yards away and limiting viewing to 30 minutes. In recent years tens of gray whales have left the usual route to spend time in San Francisco Bay and other areas, possibly searching for food.
Did you know?
Gray whales carry barnacles on their skin.
Barnacles and tiny whale lice live on gray whales, most of all on their heads and tails.
Barnacles and cyamid amphipods concentrate on the head and flukes, giving gray whales their crusty, mottled appearance.
A whale comeback, with ups and downs
Long ago, people hunted gray whales.
Then people made rules to protect them. The gray whales came back! Scientists count them to check on them.
Whaling once brought gray whales close to disappearing. Rules to protect them began in the 1930s, and the North American group recovered so well that in 1994 it was taken off the U.S. endangered species list. The group near Asia is still endangered, with fewer than 300 whales.
Since about 2016 the numbers have gone up and down, and many whales have been found stranded, some of them skinny. Scientists count the whales from the shore in most years. Their newest estimate for the group that travels along North America's west coast is about 17,750 whales (2026). People are also changing shipping lanes and slowing boats to avoid hitting whales.
Commercial whaling drove both Pacific populations close to extinction. A League of Nations ban in the mid-1930s was the first international agreement to protect a whale species from commercial whaling, and the ban has continued since the late 1940s under the International Whaling Commission. The eastern population was delisted under the U.S. Endangered Species Act in 1994; the western population, estimated at fewer than 300, remains endangered. The IUCN's global assessment (published 2018) lists the species as Least Concern.
The Eastern North Pacific population peaked at about 27,000 around 2016, then declined; NOAA declared an unusual mortality event from 2019 to 2023, and the 2025 estimate of about 12,890 was one of the lowest since counts began in the late 1960s. NOAA's newest estimate (July 2026) is about 17,750 (15,930 to 20,530), a rise researchers say likely exceeds what births could produce, so the assumptions behind the count are being re-examined. Threats include entanglement, vessel strikes, noise, disturbance and climate-driven changes to Arctic prey.
IUCN Red List
How is the gray whale doing in the wild?
- Least Concern (this animal)
- Near Threatened
- Vulnerable
- Endangered
- Critically Endangered
- Extinct in the Wild
- Extinct
Least Concern
Not at risk of disappearing from the wild right now.
See the IUCN Red List assessment · The IUCN Red List of Threatened Species 2022.2
Amazing facts
-
Gray whales carry barnacles on their skin.
Barnacles and tiny whale lice live on gray whales, most of all on their heads and tails.
Barnacles and cyamid amphipods concentrate on the head and flukes, giving gray whales their crusty, mottled appearance.
-
Gray whales swim very, very far every year.
A gray whale's yearly round trip is about 16,000 kilometers, and some swim more than 22,000.
NOAA Fisheries gives a round trip of about 10,000 miles, in some cases upwards of 14,000, one of the longest annual migrations of any mammal.
-
Gray whales leave holes in the seafloor.
When gray whales feed, they leave long trails of mud and pits in the seafloor.
Suction feeding on benthic prey leaves mud plumes and 'feeding pits' on the seabed.
-
Some gray whales are curious about boats.
In some places, gray whales are curious about boats, which has made them stars of whale watching.
Their curiosity toward boats in some locations has made gray whales a focus of ecotourism along western North America.
Words to know
- migration
- a long journey animals make at the same time every year
- baleen
- comb-like plates in some whales' mouths that strain food from water
- barnacle
- a small shelled animal that sticks to rocks, boats and whales
- lagoon
- a shallow body of seawater sheltered from the open ocean
- amphipod
- a tiny shrimp-like animal
- calf
- a baby whale
Discovery challenge
-
Where does a gray whale find its food?
Where do gray whales find most of their food?
What kind of feeder is the gray whale?
- In the mud on the seafloor
- In the tops of trees
- In rivers on land
Show the answer
In the mud on the seafloor
They suck up mud and keep the tiny animals in it.
They roll on their sides and suck up mud from the seafloor, straining out tiny animals.
A benthic suction feeder that filters amphipods and other invertebrates from sediment.
-
Where are many baby gray whales born?
Where do eastern gray whales spend the winter and have many of their calves?
Where are the eastern population's main wintering and calving areas?
- Shallow lagoons in Mexico
- Under Arctic ice
- In a freshwater lake
Show the answer
Shallow lagoons in Mexico
Many are born in shallow water near Mexico.
Calves are born during migration or in the shallow lagoons and bays of Baja California, Mexico.
The lagoons and bays of Baja California, Mexico, from early January to mid-February.
-
What lives on a gray whale's skin?
Which animals ride on a gray whale's skin?
Which animals encrust the gray whale's head and flukes?
- Barnacles and whale lice
- Birds' nests
- Frogs
Show the answer
Barnacles and whale lice
Barnacles and whale lice live on its skin.
Barnacles stick to the skin and whale lice crawl among them, mostly on the head and tail.
Barnacles and cyamid amphipods, densest on the head and tail.
-
In which ocean do gray whales live?
In which ocean are gray whales found today?
Which ocean basin holds the gray whale's only surviving populations?
- The Pacific Ocean
- The Indian Ocean
- The Southern Ocean
Show the answer
The Pacific Ocean
Gray whales live in the Pacific Ocean.
Today they are only regularly found in the North Pacific Ocean.
The North Pacific, with one eastern and one western population; gray whales are no longer regularly found in the North Atlantic.
Places where you might see it
-
Watch
Country
Mexico
Mexico is a large country in southern North America, between the Pacific Ocean and the Gulf of Mexico. It has smoking volcanoes, ancient cities built by the Maya and other peoples, and about 132 million people, many of them in and around Mexico City.
-
Watch
Country
United States
The United States is a large country in North America made of 50 states, from icy Alaska to the warm islands of Hawaii. It has the Grand Canyon, the Mississippi River and Yellowstone, and about 342 million people live there.
-
Watch
Country
Canada
Canada is the second-largest country in the world, stretching across the north of North America from the Atlantic to the Pacific and up into the Arctic. It has the Rocky Mountains, thousands of islands and about 42 million people, who speak English, French and many other languages.
Explore next
-
Watch
Country
Mexico
Mexico is a large country in southern North America, between the Pacific Ocean and the Gulf of Mexico. It has smoking volcanoes, ancient cities built by the Maya and other peoples, and about 132 million people, many of them in and around Mexico City.
-
Watch
Country
United States
The United States is a large country in North America made of 50 states, from icy Alaska to the warm islands of Hawaii. It has the Grand Canyon, the Mississippi River and Yellowstone, and about 342 million people live there.
-
Watch
Country
Canada
Canada is the second-largest country in the world, stretching across the north of North America from the Atlantic to the Pacific and up into the Arctic. It has the Rocky Mountains, thousands of islands and about 42 million people, who speak English, French and many other languages.
-
Watch
3D
Animal
Humpback whale
The humpback whale is a baleen whale famous for leaping out of the water, slapping its giant flippers and singing long, complex songs. It lives in every ocean and makes one of the longest journeys of any mammal, between cold feeding waters and warm waters where calves are born. Once hunted almost to extinction, it is now recovering.
-
Watch
Animal
Blue whale
The blue whale is the largest animal ever to live on Earth, bigger than any dinosaur. It is a baleen whale: instead of teeth it has bristly plates that strain huge mouthfuls of seawater to catch krill. Blue whales live in every ocean except the Arctic, and their deep calls are among the loudest sounds made by any animal.
-
Watch
3D
Animal
Orca
The orca, also called the killer whale, is the largest member of the dolphin family and the ocean's top predator. Orcas live in every ocean, in close family groups called pods, made up of orcas related through their mothers. Each group has its own favorite foods, hunting tricks and even its own calls, which young orcas learn from their families.
-
Watch
Animal
North Atlantic right whale
The North Atlantic right whale is a large black baleen whale that lives along the east coast of North America. It filters tiny animals called copepods from the water and has rough white patches on its head that are different on every whale. It is one of the most endangered large whales, with about 384 left (2024), and many people are working to protect it.
-
Watch
Animal
Vaquita
The vaquita is one of the smallest members of the whale, dolphin and porpoise family, and the most endangered marine mammal in the world. It lives only in the northern Gulf of California in Mexico. In 2025, survey teams saw between 7 and 10 different vaquitas and at least one new calf, and many people are working to keep them safe from fishing nets.
For parents & teachers
What children will learn
- Describe the gray whale's body, including baleen and the animals living on its skin.
- Explain how gray whales feed on the seafloor.
- Trace the gray whale's yearly migration on a map and explain why it travels.
- Understand how gray whales recovered from whaling and why scientists still count them.
Recommended ages: 3 to 17 · About 15 minutes
Talk about it
- Why might a mother gray whale travel to shallow lagoons and bays to give birth?
- Why do you think counting whales from the shore is tricky?
- How can boats and people help keep whales safe along busy coasts?
Try at home or in class
- Mix sand, water and small pasta shapes in a tray, then use a kitchen sieve to separate the 'food' from the 'mud' like baleen.
- Find Alaska and Baja California on a map or globe and trace the gray whale's journey along the coast with your finger.
Key vocabulary: migration, baleen, barnacle, lagoon, amphipod, calf
Where these facts come from
- The IUCN Red List of Threatened Species , International Union for Conservation of Nature (IUCN terms of use (no redistribution of Red List data or range maps))
- GBIF Backbone Taxonomy and GBIF Occurrence Search , Global Biodiversity Information Facility (CC0 1.0 (backbone); occurrence counts are facts derived from records under CC0, CC BY and CC BY-NC)
- Gray Whale , NOAA Fisheries
- West Coast Gray Whale Estimate Shows Increase, New Count Determines (July 2026) , NOAA Fisheries
- Gray whale , Monterey Bay Aquarium
- Eschrichtius robustus (Gray Whale), 2018 global assessment , IUCN Red List of Threatened Species
- Wikidata , Wikimedia Foundation (CC0 1.0)
- Wikimedia Commons , Wikimedia Foundation (Per file: Public domain, CC0, CC BY or CC BY-SA only (credited on each page))
Checked, not yet human-reviewed. Last updated October 28, 2026. Spotted a mistake? Tell us.