How Do Whales Drink Milk Underwater?

Written by Heather Hall
Updated: October 13, 2023
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Quick Answer:

  • Instead of sucking the milk out of its mother’s feeding glands, the mother injects the milk into her baby’s mouth.
  • She can accomplish this by squeezing special muscles around her feeding glands.
  • This pushing action makes it possible for a baby whale to take nourishment underwater.

When you think of a mammal nursing its young you may picture a dog nursing her puppies or a mother fox nursing her kits. You may even imagine a baby giraffe getting milk from its mother. But do you ever envision a baby whale nursing its mother way out in the ocean? Just like those animals mentioned above, whales are mammals too. And yes, a mother whale nurses her baby. This brings up a basic and practical question: How do whales drink milk underwater?

Keep reading to find out how a mother whale is able to feed her baby underwater. Also, learn how long whales nurse their young, the special nutrients in a whale’s milk, and just how big a newborn whale can be!

How Do Whales Drink Milk Underwater?

A baby whale starts nursing immediately after it’s born. The natural instincts of a baby whale combined with scent help it to know where to nudge its mother when it’s hungry for milk. A mother whale has what are called mammary slits. These are folds of skin that protect the feeding glands or nipples, of a mother whale. A baby whale nudges this area when it is ready to drink milk.

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Here’s how whales drink milk underwater: Instead of sucking the milk out of its mother’s feeding glands, the mother injects the milk into her baby’s mouth. She is able to accomplish this by squeezing special muscles around her feeding glands.

Other mammal babies like kittens and puppies nurse by drawing the milk out through their mother’s nipples. A mother whale does the opposite. She pushes the milk into her baby’s mouth instead of the baby drawing the milk out. This pushing action done by female whales is what makes it possible for a baby whale to take nourishment underwater.

Whales Drink Milk Underwater humpback
A Humpback Whale with her calf in the Pacific Ocean. A humpback whale baby is weaned at around seven months when it begins to eat small fish and other sea creatures.

©Imagine Earth Photography/

How Does a Baby Whale Avoid Taking in Water as It Nurses?

While nursing underwater, you may wonder how a baby whale can take in its milk without taking in a lot of seawater right along with it. The reason a baby whale is able to nurse without taking in water has to do with its tongue. A baby is able to curl its tongue into a tube-like shape that fits with its mother’s feeding gland, or nipple. This unique fit doesn’t allow anything but milk to go into a baby whale’s mouth.

How Long Do Baby Whales Nurse?

The answer to this question varies among whale species. A toothed whale may nurse her baby anywhere from one to three years.

Alternatively, a bowhead whale continues nursing her baby for six to twelve months. A beluga whale calf nurses from its mother for 20 months to two years.

Some female whales only reproduce every two years while others reproduce every five years. This makes it possible for a mother whale to continue nursing her baby for an extended period of time.

Why is a Mother’s Milk So Important to a Baby Whale?

The milk of a mother whale contains a lot of fat. In fact, some whale milk has 35 to 50 percent fat. This high-fat content is important to the survival of a baby whale. The fat supplies a baby whale with the energy it needs to continually move through the water with its mother.

A mother’s milk helps a baby to develop a thick layer of blubber that will keep it warm in cold ocean waters. In addition, milk is important for bone development, and it gives a baby whale the nutrients it needs to nurture a healthy immune system.

Whales Drink Milk Underwater beluga
Beluga whale mother with a young calf. A beluga whale baby only starts to eat solid food at around 12 to 18 months old.

©Christopher Meder/

When Are Baby Whales Weaned?

Once again, the answer to this question depends on the species of the whale. A humpback whale baby is weaned at around seven months. It begins to eat small fish and other sea creatures. Alternatively, a beluga whale baby starts to eat solid food at around 12 to 18 months old.

Keep in mind that despite being able to eat small sea creatures, most baby whales continue to nurse as well. The nutrients of its mother’s milk along with solid food add to the strong development of a baby whale.

Why Can’t Humans Drink Whale Milk?

Sperm whale and her calf swimming at the surface, Indian Ocean, Mauritius.

Whale milk has an extremely high fat content and a consistency that is compared to toothpaste.


Whale milk is designed to be ingested by whale calves and while it may not really be suitable for human consumption in its natural state, there are those that are looking into how realistic it is to sell it. However, there are a variety of reasons why whales’ milk should be left to whales. Some of these are:

  • Fat content – whale milk has an extremely high content of fat, made up of 35 to 50% fat, and also comes in very large amounts. A blue whale produces almost 441 pounds of milk per day. Should you ‘drink’ this milk, you will most likely see an increase in your body weight.
  • Consistency – these mammals have milk that is incredibly thick often likened to butter or toothpaste. It is made like this for a reason as it needs to pass through water without disintegrating.
  • Taste – whale’s milk is said to taste like a combination of castor oil, fish, liver, and milk of magnesia.

There have been instances where whales’ milk has been turned into cheese, and this is where its fat content can be an asset. Thanks to this high fat, the consistency has been creamy. It is said to have a salty, sea taste, reminiscent of fresh oysters.

The photo featured at the top of this post is © Achimdiver/

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About the Author

Heather Hall is a writer at A-Z Animals, where her primary focus is on plants and animals. Heather has been writing and editing since 2012 and holds a Bachelor of Science in Horticulture. As a resident of the Pacific Northwest, Heather enjoys hiking, gardening, and trail running through the mountains with her dogs.

FAQs (Frequently Asked Questions) 

How many babies does a mother whale have at one time?

A mother whale has one baby at a time. This makes sense because a mother whale is only able to nurse one baby.

What is the gestation period of a whale?

The gestation period of a whale can be 9 months all the way up to 17 months. It all depends on the type of whale you’re talking about.

For instance, a sperm whale is pregnant for around 590 days, which adds up to 19 months. Alternatively, a bowhead whale’s gestation period lasts 13 or 14 months.

What is in a mother whale’s milk?

A mother whale’s milk is filled with nutritious fat and protein. This milk allows a baby whale to gain hundreds of pounds each day to form a thick layer of blubber. This blubber is absolutely necessary for its survival.

A blue whale baby gains about 200 pounds per day by feeding on its mother’s milk.

Where does a mother whale swim when her baby is nursing?

When a baby whale nudges its mother to let her know it is hungry, the mother swims near the surface of the water. She does this so her baby can nurse and take a breath above the surface whenever it needs to. Being a mother whale is a full-time job!

What is a baby whale called?

A baby whale is called a calf. A mother whale is known as a cow and a male whale is a bull.

How big is a newborn baby whale?

As you may have guessed, baby whales of all species are large. Of course, some are larger than others.

It’s not unusual for a newborn blue whale to measure 23 feet with a weight of 5,000 to 6,000 pounds. Bear in mind that an adult blue whale is around 90 feet long and weighs 100,000 pounds or more.

On the other end of the spectrum, a newborn beluga whale weighs from 119 to 140 pounds and is around five feet long. In the world of whales, belugas are considered small.

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