Do Otters Lay Eggs?

Wild animals can be very successful at breeding. Otters are sort of good at that. 

Often confused for beavers, minks, and muskrats, otters are soft and cuddly animals often found around water. 

There is some confusion when it comes to the way otters reproduce. Some say that otters hatch, while others claim that otters give birth. Which one is it then; do otters lay eggs?

In this post, we’ll address some widespread misconceptions about otter “eggs”.

Do Otters Lay Eggs?

otter couple

No, otters do not lay eggs. Contrary to what people believe, otters are mammals that give birth to live young. Female otters will usually give birth to one to three babies that are born blind and helpless.

Generally speaking, there are two main options for animals to bring their offspring into the world.

They will either lay eggs and have no physical connection with the baby (oviparity), or they will let the embryo (later fetus) develop inside them, and when the time is right, give birth to a live young (viviparity).

Otters are, as we just mentioned, viviparous.

Both styles of giving birth have some advantages, but also drawbacks. 

Advantages And Disadvantages Of Otters Laying Eggs

The main benefit of an otter hatching would be freedom and mobility; the mother would not be slowed down by having to carry lots of eggs in her belly. 

The biggest disadvantage of laying eggs would be the exposure of the otter’s eggs to some predators, weather, and other environmental changes. Letting the baby develop inside the reproductive tract allows the otter mother to protect it until it’s ready to be born. 

Why Don’t Otters Lay Eggs?

Otters don’t lay eggs because it is more beneficial to them to give birth to live offspring. 

Millions of years ago, every animal laid eggs.

As time passed, some animals slowly evolved and started giving birth to live babies because that was what helped them survive and get their species to the next generation. 

And this was what most likely happened with otters. It was dangerous for otters and their ancestors to have their shell-covered offspring sitting out in the environment, so they adapted to keeping their babies inside them for as long as possible. 

And one of evolution’s ways of getting to the next generation of otters was for them to give birth to live young. 

The main problem for those new otter generations is humans. Many otter species are hunted down for their fur, leading to them becoming endangered. 

Sea otters, found along the coasts of the Pacific Ocean in North America and Asia, were hunted so much for their fur between the 18th and 20th centuries that their population fell to 1,000–2,000 individuals living in a fraction of their historic range. 

Species that are listed as endangered and face a very high risk of extinction are the neotropical, southern, marine, giant, and Congo clawless otters.

How Do Otters Give Birth?

Otters become sexually mature from the age of two to four, depending on the species. Many otter species, including the sea otter, will breed throughout the year and stay with the same partner for life (monogamy). 

In some species of otters (there are 13 in total), copulation can be quite aggressive, as a male might bite the female’s nose or grab it by the neck. Usually, the copulation happens in water and lasts from 10 to 30 minutes.

Otters use a special reproductive strategy called delayed implantation, also known as the embryonic diapause. This means that the otter will temporarily stop the development of the embryo, delay the pregnancy, and give birth when the environmental conditions are right.

If the copulation is successful, the female will stay pregnant from 60 to 86 days. 

Sea otters will give birth in the water while other otter species birth their young in dens.

Most freshwater otters will have one litter every year with one to four pups. The Asian small-clawed otter will have two litters per year with up to 6 pups. Sea otters will only have one pup per year and females will nurture their young while floating on their backs. 

Giant otter pups weigh about 7 oz at birth, while the river otter pups average about 4.6 oz.

The male, female, and older offspring will take care of the newborn. The baby will leave the otter den (also known as a holt or couch) after a month and start swimming after two months. It stays with its family for around 6 months to a year before becoming independent. 

Otters can live up to 16 years and mostly feed on aquatic wildlife, including fish, crayfish, crabs, frogs, birds’ eggs, birds, some reptiles, and even small mammals like muskrats and rabbits.

Animals That Lay Eggs

According to the University of Georgia, over 99% of the world’s animals reproduce by laying eggs. That’s because most of the animals in the world are insects, and most insects hatch from eggs. 

Over 99% of mammals give live birth, including otters. Out of around 6,500 known mammal species, only the platypus and the echidna lay eggs.

Most reptiles lay eggs. Out of approximately 11,000 known species of reptiles, over 80% lay eggs. The only exceptions are some snakes and lizards that give live birth.

Most fish lay eggs. Out of around 34,000 known species of fish, less than 400 are livebearers. This includes guppies, mollies, platies, swordtails, and some sharks. 

All species of birds lay eggs. This includes all of the 10,000 recognized species of birds. Some ornithologists claim there are twice as many bird species, around 20,000.

Almost all amphibians lay eggs. Out of around 8,000 amphibian species, most will lay eggs in freshwater habitats. There are only a few amphibian species that give live birth (several frog species).

Almost all insects reproduce by laying eggs. Out of 1 million known species of insects, of which 350,000 are beetles, all lay eggs. The only exceptions are a beetle from Borneo, another from South America, and some aphids.

Final Thoughts – Do Otters Lay Eggs?

In conclusion, otters do not lay eggs. These carnivorous mammals reproduce viviparously and give birth to one to four babies in one litter. 

The main reason why otters do not lay eggs is evolution; giving birth to live young helped otters procreate and survive to this day.

Animals that hatch will have eggs that come in different forms! Some will have blue or white color, speckled patterns, and different textures, while others will be hard, soft, or even gooey. Animals may decide to lay them in the water, underground, or a nest. Otters are not such animals.

If you were pondering on the question “do otters lay eggs”, we hope this article removed all doubts.

And if you enjoyed it, here’s a recommendation on another popular read on otters: Are otters members of the rodent family?

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