How Do Dolphins Breastfeed Underwater?


I was lucky enough to be in Bali recently on a dolphin watching trip. I wanted to know how dolphins breastfeed their young underwater, so I asked one of the guides. His answer left me with some questions, so I looked into this further when I got back to shore.

Dolphins have inverted nipples inside mammary slits. When the calf is ready to feed, they dive underneath the mother and nudge the mammary slits. The nipple is released and the mother feeds milk to the calf that rolls their tongue into a u-shaped tube.

I found this interesting and wanted to find out some more information. If you want to find out more, please read on.

If you or someone you know loves dolphins then check out my favorite dolphin gifts on AmazonOpens in a new tab..

How Do Dolphins Breastfeed Underwater? 

All mammals have evolved and developed different, unique mechanisms that enable them to survive in their environments. In the case of dolphins, they have their mechanisms of breastfeeding underwater. Whales are surrounded by water and breastfeeding in this kind of environment is not as easy as it would be for a land mammal.

Dolphins have two mammary slits on their underside which have an inverted nipple inside. The nipples are not the same as terrestrial mammals that have protruding nipples, and young dolphins can not feed at any time as land mammals can.

When the dolphin calf is ready to feed, they dive underneath the mother and nudge the mammary slits. This signals to the mother that the calf is ready to feed. This also works as a way to stimulate the mammary slit to release the nipples.

Whereas the young of land mammals will regulate the amount of milk they take from their mother, marine mammals are different.

Dolphin calves do not control how much milk they take, but the mother does. The mother squirts their milk from their teats into the calf’s mouth.  

The young calf wraps their mouth around the teat, rolling their tongue into a u-shaped tube. The rolled tongue is then pressed onto the upper palate and placed around the nipple.

This ensures that the milk is channelled directly into the mouth, and ensures that none of the fluid is lost into the water. 

The mammary glands of the dolphin have muscles that first contracts, then shoots out milk directly into the mouth.

During the first few weeks after birth, the mother will lay on her side to help the young find the mammary glands.  

After the first few weeks, the calf will lay on their side to drink the milk and the mother slow down their swimming.  

One of the main reasons why dolphins can successfully breastfeed underwater is due to the consistency of the milk. Whale milk has an unusually high-fat content.

The high-fat content makes the milk thick enough to pass through the water. High-fat concentration in the milk is important because the adult female whale can eject liquid into the calf’s mouth without it dissolving into the water around their lips.

If you want to know how whales breastfeed underwater, I have written an article which you can find here.

Do Dolphins Produce Milk?

Dolphins are sea mammals and possess the typical characteristics of all mammals. This means that they have mammary glands and produce milk to feed their young. 

With all species of dolphin, the calves require plenty of milk for them to grow and stay healthy. Generally, a baby dolphin consumes milk every 20 minutes, 24 hours a day. As they get older, this happens less frequently.  

Dolphins have been seen to nurse their young for up to four and a half years, generally with a minimum of two years.

Do Dolphins Have Nipples?

Dolphins do have nipples, but they are not extended on the outside as in humans. Dolphins spend their entire life inside the water, so nipples and breasts being on the outside would not be the best place for them. Dolphin nipples are enclosed within folds of skin referred to as mammary slits. 

How Does Dolphin Milk Taste?

The milk of a dolphin has a very thick consistency. The thickness is attributed to the high-fat concentration that can reach between 108 to 180 gm per liter. The milk is white in appearance with a yellowish tinge and a creamy consistency.

The taste is oily and lacks sweetness and has a fishy odour. (Please don’t ask me how I know!!)

How Long Do Dolphins Breastfeed?

Baby dolphins need the milk to survive and to grow. Once they are large enough to survive without the milk, then they will change to a diet of mainly fish.

Most dolphins will stay with their mothers for at least three years. Some calves will nurse up to the age of six, or even ten in some cases.

Calves can grow extremely fast in their first year, reaching seven times as large as when firstborn, due to the high-fat content in the milk.  

Dolphins give birth to their next calf only when the previous calf has been fully weaned. Due to this, dolphins will only have another calf after at least three years.  

Dolphins do not reproduce very often, which allows plenty of time for the calves to grow fully and also to increase the chances of their survival.

The mother will lactate and produce milk until the calf has been weaned.

What is the Importance of Milk to the Young Dolphins? 

Similar to land mammals, milk is a vital part of a young dolphins existence. Baby dolphins need milk for healthy nourishment and growth. Dolphin calves survive on milk until they are ready to wean. Without milk, dolphins have very low survival rates, starving to death. A newborn dolphin consumes large amounts of milk in a day and is their sole source of food at this time.

The milk is rich in nutrients required for the baby dolphin to grow and thrive. The liquid is packed with healthy fats that provide energy calf. Other nutrients are required to boost the immune system, support bone development, and ensure that the brain functions properly.

Fast moving rough-toothed dolphin

Breastfeeding creates a bond that is unbreakable between the mother and her calf. This bond is important for the development of the baby whale. 

Research has proved that the relationship between marine mammals and their parents is crucial for their survival. Marine mammals living in captivity have a shorter lifespan than their counterparts in the wild. In captivity, dolphins cannot nurture naturally as they would in the wild.

Dolphin milk contains a high concentration of fatty acids. The fat in the milk helps develop blubber. Blubber is a thick layer of fat under the skin of dolphins.

Blubber develops as the dolphin grows. Since dolphins spend all of their time underwater, they need to prevent loss of heat and to keep their body temperatures constant.

Blubber acts as an insulating layer against the coldness of the water. The high-fat content from the milk enables the thick insulating fat layer to develop.

If you or someone you know loves dolphins then check out my favorite dolphin gifts on AmazonOpens in a new tab..

If you want to find out more about blubber, I have written an article here.

Recommended Books

Guide to whale watching in North America : USA, Canada, Mexico. Where to go, what to see.Opens in a new tab.

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Handbook of Whales, Dolphins and Porpoises Of the WorldOpens in a new tab.

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Encyclopedia of Whales, Dolphins and PorpoisesOpens in a new tab.

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Bryan Harding

Bryan has spent his whole life around animals. While loving all animals, Bryan is especially fond of mammals and has studied and worked with them around the world. Not only does Bryan share his knowledge and experience with our readers, but he also serves as owner, editor, and publisher of North American Mammals.

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