The gray whale is a large marine mammal of the baleen whale suborder and belongs to the cetacean family.
This includes dolphins and porpoises.
During the whaling industry between the 17th and 20th centuries, the gray whale was mainly hunted for its oil until it became nearly extinct.
Fortunately, with the aid of organizations and the government, marine mammals such as the gray whale are now a protected species, and hunting them is considered illegal.
Today their numbers have grown, and it is estimated that there are at least 20,000 gray whales currently in existence since the end of the commercial whaling era.
Physical Appearance and Anatomical Characteristics
When fully grown, the gray whale can grow to over 50 ft. long; their average size is closer to 44 – 48 ft. long. As with other baleen whales, the female gray whales usually grow slightly larger than their male counterparts.
In terms of weight, these marine mammals can measure up to 40 tons when fully developed.
The gray whale is a dark grayish slate color with white patches covering its body, hence its name.
In many cases, these marine mammals may also be covered in parasites and other organisms, causing their skin to look discolored and making the gray whale look like crusty ocean rock.
The gray whale has thick insulated blubber to stay warm in cold waters up to 10 inches thick.
Compared to most other baleen whales, their baleen bristles are relatively short.
Instead of having a dorsal fin like other whale species, the gray whale has a small dorsal hump down the far end of its back.
Swimming is assisted by fan-like flukes, in which the whale moves up and down to propel itself through the water.
As with other cetaceans, the gray whale also has a pair of flippers to help it steer and turn when swimming.
Because these whales belong to the baleen whale suborder, they possess baleen plates with bristles attached to them, which they use to filter their prey from the water.
Diet and Hunting Methods
Gray whales are bottom feeders and hunt for their prey by swimming to the bottom of the ocean, turning on their side, and scooping up sediments from the seafloor.
Once their prey rises from the seafloor, these marine mammals will use their baleen bristles to filter through the water while capturing and trapping their prey in their baleen bristles, hence the term filter feeding.
Because there are small spaces between the bristles, water can pass through the bristles without a problem.
However, the bristles are packed tightly enough to prevent their prey from escaping.
Their primary diet consists of eating benthic crustaceans.
However, they will consume a variety of small prey scooped up into their path.
While adult gray whales will consume crustaceans and other prey, baby whales are fed milk until they can hunt for food.
A baby gray whale can consume as much as 80 gallons of milk daily.
Habitat and Migration
Gray whales are often found swimming in the eastern north pacific ocean and near Korea in the western north pacific ocean.
However, recent spottings in areas such as the Mediterranean sea suggests that these marine mammals may begin repopulating areas that may have become abandoned due to previous whaling activities.
Every October, small pods of gray whales make long migration trips from their feeding grounds in the Bering and Chukchi seas.
They migrate to the Baja peninsula of Mexico and the southern Gulf of California, where they mate and bear their offspring.
During migration trips, as many as 20,000 gray whales can be seen swimming in the ocean.
The migration trip takes an average of 2 -3 months to complete and is considered one of the longest migrations trips of any animal lasting 9,000 – 16,000 miles.
However, it seems that, on average, their migration trips are closer to 8,000 – 10,000 miles.
During these trips, the gray whales will travel night and day, moving at an average speed of 5 mph or less until they reach their destination.
Once they arrive at their mating grounds, they will begin courting other whales, and those that are pregnant will start giving birth to their young.
When the mating season ends, they begin their journey back to the eastern north and western north pacific ocean to feed, relax and prepare for their next mating season.
Social Structure and Communication
When it comes to communication, the gray whale communicates using loud low pitched moans, whines, and croaks.
These sounds can be heard over great distances and even underwater.
It allows other gray whales to hear and communicate with one another quite effectively.
Unfortunately, little is known or understood about the vocal communication of gray whales.
In addition to communicating vocally, gray whales are known to breach the water, spy hop, and lobtail (slap their flukes against the water).
Mating, Reproduction and Lifespan
The typical gestation period for a female gray whale (from conception to birth) lasts 13.5 months.
Most gray whales are born around mid-January and are born at an average length of 12 – 14 feet long at birth.
The baby whales are often born in shallow waters, which is believed to help prevent their young from being attacked by sharks and killer whales.
After birth, the baby gray whales will drink milk, made up of over %50 fat produced by their mother’s mammary glands.
The milk produced by the mother is high in nutrients to give the child all the nutrition it needs to develop into a healthy young whale.
The baby whale’s nursing/feeding period lasts about 6 – 8 months or until lactation stops.
After eight years, the young gray whales will reach sexual maturity and can begin mating and reproducing.
A healthy gray whale is estimated to have an average lifespan of 50 – 70 years.
Endangered Status and Predators
The gray whale was initially found living in three areas throughout the northern hemisphere.
It includes the eastern north pacific ocean, the western pacific ocean, and the North Atlantic coast.
However, these whales are currently considered extinct in the North Atlantic.
In 1994 the gray whale was taken off the untied states’ endangered list and is currently protected by international law.
10 Insightful Gray Whale Facts
- The gray whale makes up one of around 90 known species of cetacea in existence today.
- Because gray whales are marine mammals, they are warm-blooded, breathe air, give birth, and produce milk to feed their young.
- The scientific name for the gray whale is “Eschrichtius robustus.”
- Due to their aggressive fighting behaviors, when whalers would try to capture these marine mammals, they would refer to gray whales as “devil-fish.”
- Baby gray whales can consume as much as 300 gallons of milk per day during their first year of birth.
- Once a hunted and endangered species, the gray whale is now considered one of the most popular marine mammals to those participating in the whale-watching industry.
- A fully grown gray whale can weigh more than five adult elephants.
- Unlike toothed whales born with a single blowhole, the gray whale possesses two blowholes.
- The earliest ancestors of the gray whale existed over 30 million years ago.
- The only known natural predator of the gray whale is a pod of killer whales. In terms of other predators, gray whales may also face occasional attacks by whale poachers and hunters.