15 of the Hardest-Working Moms in the Animal Kingdom

The animal kingdom can be ruthless to young animals. Often, it's left to the mothers to protect and raise their young. That's not to mention all the work put in before the birth, including building nests and guarding eggs.

These meticulous mothers go to extremes to ensure the survival of their offspring, and they deserve some credit for their efforts. Here are some of the best mothers in the animal kingdom.

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Giant Pacific Octopus

red octopus against glass in aquarium — Jesse McCarty / Flickr / CC BY-NC-ND 2.0

The giant Pacific octopus is perhaps the hardest-working marine mom, laying up to 74,000 eggs in a deep den or cave and painstakingly caring for them for seven months without leaving — not even for food. While this keeps the babies safe from predators, it is an act self-sacrifice. To survive without food, female giant Pacific octopuses live off the fats and proteins within their own bodies, ultimately dying of self-cannibalization as a result.

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African Elephant

mother holds baby elephant close among tall grass — Diana Robinson / Getty Images

At two years, elephants have the longest gestation period of any mammal. They also give birth to the largest babies of any land animal, with newborns weighing up to 200 pounds. Combined, it's easy to see that the African elephant is a hardworking mother.

Elephant calves depend entirely on their mothers for feeding for their first two to three years and continue to nurse for supplemental nutrients for longer. Luckily, after all that work, elephant moms don't have to rear their kids alone. They have the help of the herd, which is comprised entirely of females and their calves.

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Gray Kangaroo

Diane Keough / Getty Images

For gray kangaroos, motherhood is all about multitasking. Babies are born at an early stage in development — just 36 days — and then make their way to their mother's pouch, where they will remain for further gestation and feeding until finally venturing out about nine months later.

Because the initial development period is so short, female kangaroos can get pregnant in quick succession, meaning they are nearly permanently pregnant. If they are carrying two joeys at different stages of development simultaneously, they can even produce two different types of milk at once to ensure that each baby gets the nutrients it needs at that time.

Even more impressive is that if needed, a female kangaroo can freeze the development of an embryo so she does not give birth again until a previous joey is able to leave her pouch.

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Virginia Opossum

mother opossum crawls on log with four babies on back — Stan Tekiela / Getty Images

The Virginia opossum can have anywhere from four to 25 babies in a single litter. However, female opossums only have 13 nipples — 12 in a circle and one in the center. Because marsupials can only feed one joey per nipple, only the first 13 babies of a litter tend to survive.

Still, 13 is a lot of babies to be responsible for at one time. They stay with the mother for about 100 days as they continue developing, eventually moving to ride on the mother's back when they grow bigger.

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Emperor Penguin

The birthing process for emperor penguins is one of collaboration between mother and father. The mother exhausts her food reserves producing an egg. After laying it, she transfers the egg to the father, an act that takes the utmost care from them both because damaging the egg would mean the death of the chick-to-be.

After the transfer, the father incubates the egg while the mother goes off to walk for months in the snow to gorge herself on fish. She doesn't keep this fish for herself though; upon returning to her newly hatched chick, she regurgitates her feast to feed the baby.

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Strawberry Poison Dart Frog

close up of red poison dart frog perched on leaf — kikkerdirk / Getty Images

While the emperor penguin mother goes the distance for her chick, the strawberry poison dart frog climbs great heights for hers. First, she lays her eggs on the Costa Rican rainforest floor. Once the eggs hatch, she carries the tadpoles one by one to individual tiny pools of water — usually in bromeliad leaves but sometimes up to the tallest trees of the rainforest canopy. She then proceeds to feed each of her tadpoles her own unfertilized eggs until they metamorphose into a froglet.

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Orca

There is no rest for orca mothers after their calves are born. The newborn killer whales don't sleep at all for the first month of their lives, which means the mother doesn't get to sleep either. Instead, they continuously swim, which helps to avoid predators and build important fat reserves and muscle. The mortality rate for young orcas is high, with between 37 and 50 percent of calves dying within the first six months of life, so it is especially important that mothers are around to provide protection.

Some orcas stay with their pod for their entire life, which means that mother and child stay together throughout their lives.

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Taita African Caecilian

gray wormlike creature coiled on rocky ground — Milvus / Wikimedia Commons / CC BY-SA 3.0

The Taira African caecilian gives the skin off her back — literally. Once this wormlike amphibian mom's eggs have hatched, she grows an extra, nutritious layer of skin that she allows the children to eat. She regrows it every three days until her squirmy young become more independent.

This behavior is called dermatotrophy. While extremely generous, it does not harm the mother.

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Tailless Tenrec

front view of tenrec sniffing in short grass — Miwok / Flickr / CC BY-NC-ND 2.0

The tailless tenrec of Madagascar can give birth to up to 32 babies in one litter. Even an average litter size of 15–20 babies means a lot of mouths to feed. Though they usually have 12 nipples, some females have been found to have up to 29, which would certainly make the feeding easier.

After about three weeks, tailless tenrecs are able to forage for nesting materials; the mother is responsible for guiding them.

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Frilled Shark

Rohit Kushwaha / Getty Images

Though little is known for certain about the mysterious, deep-dwelling frilled shark, scientists believe that females have the longest gestation period of any vertebrate — up to 3.5 years. One explanation for this extra-long pregnancy is that the intense cold this creature inhabits causes its metabolism to slow down.

As for what takes place during this extended gestation period, the frilled shark's young develop in eggs inside the female and she gives birth once they are fully developed.

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Hamerkop

PhotoStock-Israel / Getty Images

Hamerkops take their homemaking very seriously. Over the course of three to four months, these African birds will work hours each day creating a gigantic nest for their young.

The male collects materials while the female puts the intricate nest together, and then they both cover it in mud and decorate it. The final product can be as large as 5 feet wide and 5 feet tall and can support the weight of an adult human male. It can contain as many as 8,000 items.

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Alligator

They may seem tough on the outside, but alligator mothers are very caring. They build their nests among vegetation and rotting compost so that the natural heat can incubate the eggs while they stand guard.

Once the eggs hatch, an alligator mom will nearly gobble them up into her strong jaws to carry them safely into the water. The babies stay with their mom for up to two years so that she can continue to protect them while they grow. This is important because of the threat to baby alligators — up to 80 percent fall victim to predators.

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Polar Bear

To prepare for pregnancy, a female polar bear eats enough to double her own body weight, gaining upward of 400 pounds. Her next step is to dig a maternity den, usually in snowdrifts, where she will stay for the duration of her pregnancy and another two months after the birth of her cubs. When all is said and done, the mother polar bear will have fasted for about eight months.

Upon leaving the den, she then must navigate the ever-melting sea ice in search of food to keep herself and her cubs alive for the next two years, until her cubs become independent.

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Orangutan

Orangutan mothers are some of the hardest-working single moms in the animal kingdom. Young orangutans remain dependent on their mothers for the longest of all primates besides humans, nursing for up to eight years. Their mothers carry them on their bellies for their first four months of life, never leaving them without physical contact.

In addition to looking after the infants, orangutan mothers build a new treetop bed for them to sleep in every single night — more than 30,000 homes in a lifetime. They also teach them what they need to know to be independent, from finding food to building their own nests.

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Hornbill

Hornbills have a very peculiar — but undoubtedly safe — nesting habit. The mother bird builds a nest inside the hollow part of a tree. When it is time to lay the eggs and incubate, she seals herself inside using mud and fruit.

She leaves an opening that's just large enough for the father to sneak food through for her (and the chicks, once they hatch). Some hornbill moms will break out of the wall and rebuild it to keep the chick safe for a while longer.