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How Big Are Baby Whales?

Humpback baby whale size as compared to mom

There’s nothing sweeter than seeing a mother whale and calf pair traveling together through the gorgeous ocean waters of Dana Point, California, the Dolphin and Whale Watching Capital of the World®. We love hearing the oooh’s and awe’s from passengers on our whale watching safari as whales gracefully breeze past the boats. When it comes to baby whale size we must remember the very important marine fact that all dolphins are considered whales but not all whales are classified as dolphins. This is especially important when we talk about the birth of baby whales because all whale species give birth to their young at different weights, lengths, and sizes. So, how big are baby whales? Well, this depends on the species, of course.

“Cetaceans” are composed of approximately 90 different species of whales, dolphins, and porpoises. Baby whale size can be as small as mere inches if you are a Hector’s dolphin up to several yards like a baby blue whale and other larger Rorqual whales. Regardless of how big or how small a baby whale is at birth, they all have common characteristics linking them together. All whales and dolphins are mammals. This means that like us, they are born during a live birth. Baby whales also drink milk and are born with hair too. Read on to hear more answers about baby whale size to questions like how big are baby whales on day one, when they first hunt on their own, wean off their mother’s milk, reach adulthood, and more.

Do whales lay eggs or have live births?

Contrary to what some may believe, whales are not fish and do not lay eggs. Female whales carry their unborn fetus in the womb and when it is time to deliver, they will give birth to a live, oxygen breathing, baby whale. Just like we pat our babies on their backs to relieve mucus in a newborn’s lungs at birth, a mama whale brings her brand new baby calf up to the surface to breathe in the fresh air and take in the incredible first breath of life.

How big are baby whales, really?

Well, it’s not an easy answer with so many species of whales and dolphins but a good range of baby whale size begins with the smallest dolphins on earth called Hector’s and Maui dolphins which are found only in New Zealand. At birth, these cuties reach only 24-30 inches. So cute! More commonly seen dolphins in our waters off the pacific coast are short and long-beaked common dolphins, bottlenose dolphins, pacific white-sided dolphins and Risso’s dolphins. Common dolphins are born at about 24-36 inches and around 20 pounds with bottlenose baby dolphins being slightly larger weighing up to 40 pounds and reaching closer to 38-48 inches in length. Pilot whales are also larger in size and are born weighing 225 pounds and already reach lengths of up to 6 feet. The smallest whale on record is the dwarf pilot whale, only reaching about 3.3 feet as a brand new baby. The largest dolphin species within the family of dolphins is Orca. This apex predator of the sea delivers babies who are closer to 8 feet long at birth and are already 350 pounds. Other toothed whales include the sperm whale whose little ones are not so little. How big are baby whales in the sperm family of whales? The answer is, enormous! Weighing as much as a grown adult African elephant and measuring 13 feet, sperm whale babies are BIG babies! But sperm whales do not hold the title for the biggest baby whale size.

Being the largest animal to have ever been on planet earth also gives you the title of having the largest babies in the entire animal kingdom! So, how big is a baby blue whale? On their first day of life, the baby whale size of blue whales begins at an astonishing 23 feet. Can you believe it? That is about the same size as a full-grown African elephant. Winning the second place title is the fin whale whose sweet little ones are also not so little. How big are baby whales in the family of fin whales? These gentle giants are approximately 18 feet long and already weigh between 4,000 to 6,000 pounds at birth. Lucky for us, this region is home to a vast variety of whales including humpback whales and the smallest whale species of the great Rorquals, known as minke whales. Humpback whales also are large and in charge weigh about one ton at birth and reach larger lengths of about 10 feet on the day of their birth. The smallest of the baleen whales is known as the minke whale. While not so little, these elusive and shy whales are the lightest and the shortest of the rorquals weighing a mere 700 to 1,000 pounds at birth and about 8 to 11.5 feet in length. Not so small if you ask us!

Where are baby whales born?

Passengers often want to know how big are baby whales in each ocean. Whales perform great migrations to undergo the incredible experience of birthing their young. Some migrations are quite short and some are extremely vast. More than half of Northern Pacific humpback whales will travel 3,000 miles to give birth to their young in the warm waters of Hawaii. Gray whales and blue whales provide us with extraordinary examples of whale species traveling further than any other type of whale to give birth to their young. A gray whale’s migration to give birth lasts anywhere from 12,000 to 14,000 miles round trip! Now that is a whaley long trip! Whale size does tend to vary just slightly in different parts of the world. For instance, whales in the Southern Hemisphere have been recorded to grow larger and longer than whales in the Northern Hemisphere. When we are asked how big are baby whales, we cannot overlook this amazing journey that whales take to experience birthing their calves.

How often do whales have babies?

Baby whale size as well as how often whales give birth is widely dependent on each whale species. This is primarily because different species of whales reach sexual maturity at different times in their life. Due to varied gestational periods, they also have their young at different times throughout the year and their lifetime. Whale species will also nurse their young for different lengths of time. For instance, bottlenose dolphins and humpback whales reproduce every 2 to 3 years while other species such as Risso’s dolphins will only reproduce once every 6 years. Pilot whales reproduce approximately every 3 to 5 years. Baby beluga whales will remain near mama, sometimes for 3 years or even longer. The larger sperm whale has a longer gestation period and may nurse their young for just over a year while minke whales may only nurse for 5 to 10 months.

How long is a whale’s gestation period?

Typically, whales tend to breed more often in the winter months so that they can birth their young in warmer waters towards the end of their migration. On average, whales will carry their young anywhere between nine to 16 months. Many species of dolphin, blue whales, fin whales, sei whales, humpback, Bryde’s whales, and minke whales all have a gestation period very similar to humans, lasting approximately 10 – 12 months while sperm whales have a much longer gestation period lasting closer to 18 months. Pilot whales also have a longer gestation period, lasting anywhere from 12-15 months long. When it comes to gestation, baby whale size is not affected by the length of gestation unless the offspring is born prematurely. While this is not common, premature births occur for a variety of reasons, usually leading to detrimental outcomes.

How are baby whales delivered?

How big are baby whales has nothing to do with how baby whales are physically born into the world. Since all whales breathe oxygen from the surface of the water, a whale’s blowhole is their lifeline. Their anatomy is so precious that during birth, a baby whale (or dolphin) is born in what we know on land as a “breech” position. With cetaceans, this means their tail is delivered first. This behavior protects the newborn whale’s blowhole and helps to ensure that mom can push them out and up to the surface just seconds after birth, so they can take in those precious first breaths of life.

“Baby beluga in the deep blue sea

Swim so wild and you swim so free

Heaven above and the sea below

And a little white whale on the go

You’re just a little white whale on the go.”

Do whales and dolphins have umbilical cords?

One super fun whale fact about the birth of baby whales and dolphins is that like us, they are all born with belly buttons. Also, like us, their belly button is the remnants of the loss of their umbilical cord – a forever tattoo of where the unborn baby was attached to its mother. How big are baby whales when they are wrapped inside their mom’s uterus? Very similarly to humans, baby whales and dolphins are curled tightly inside their mother’s womb until they are born. Foetal folds are visible creases in the calf’s skin and blubber that can be seen from days to a few short weeks after a baby whale is born. Foetal folds continue to fade as youngsters mature. As baby whale size changes after birth, so do the markings on their skin. It is always an exciting moment to see baby whales and dolphins out on trips and even more precious when we see brand new little ones still showing off their adorable foetal folds.

Can whales have more than one baby?

Nearly all whales and dolphins are considered uniparous. This means they typically only give birth to one baby at a time. While considered extremely rare, cetaceans in the whale and dolphin species can have twins but this has been recorded in very low numbers, occurring in less than 1% of all births. Sei whales rank the highest at just barely over 1% for having multiple babies at once and are generally always fraternal twins, meaning they have developed from two separate eggs. Since whales do not employ midwives, doctors or doula’s like we do on land, delivering their little ones and often find themselves delivering their young while alone, and some like the gray whale, within the presence of their larger migratory groups.

How do baby whales drink milk underwater?

Have you ever heard of hydrodynamics? According to Webster Merriam’s dictionary, hydrodynamics is defined as “a branch of physics that deals with the motion of fluids and the forces acting on solid bodies immersed in fluids and in motion relative to them. A mother whale’s body relies on hydrodynamics too because babies are completely dependent on them for their main source of food. How big are baby whales’ appetites? Baby whale size is dependent on being able to feed properly underwater. When it is time to eat, a baby whale will nudge their mother near its belly. This nudging behavior lets mom know “I’m hungry and it’s snack time.” Since whales and dolphins do not have lips and toothed whales have teeth, the mother’s nipple remains inverted until the baby performs this behavior. When all signs point to feeding time, milk will shoot out of the extended mammary gland, almost injecting a baby whale’s mouth with milk. Pretty cool right? We think so too!

What happens if the baby becomes unwell?

The toughest journey for a baby whale or dolphin is during their first year of life. Baby whales are most vulnerable during this time and potential predators anticipate moments when mom isn’t watching carefully. Transient orcas are carnivores, making baby whales and dolphins of all ages and sizes a favorite meal on the ocean’s menu. Sharks also prey upon young whales because they are easy slower-moving targets that create a large food source when food is scarce. The toughest journey for a baby whale or dolphin is during their first year of life. Baby whales are the most vulnerable during this time due to both their surroundings and potential predators.

How long will baby whales nurse?

Because all baby whales rely solely on their mothers, how long each baby whale nurses depends on the species and will often range from 6 months to over 2 years. How big are baby whales when they nurse? Since whales spend their entire lifetime underwater, they require additional fat layers called blubber to keep them insulated in temperate waters. Although humans and whales are similar in that both babies both drink milk, whale milk is much richer and contains a much higher fat content. High concentrations of fat within the mother’s milk help ensure babies can quickly gain thick layers of blubber. To grow those deep layers of insulation, rich whale milk contains roughly over 10% – 50% fat. The healthier a baby whale becomes with age through drinking mama’s milk, the more significantly baby whale size changes.

Are all baby whales born with teeth?

Just like our own species, dolphins are born with teeth embedded within their gums. While it takes most humans several months to erupt teeth through the gums, dolphins’ teeth typically emerge within the first 5 weeks of their life. Unlike humans, dolphins are only born with one set of teeth to last their entire lifetime. Also unlike human teeth, the layers of teeth multiply each year at the root of the tooth. Scientists and researchers alike can tell the age of a dolphin just by looking at their teeth and examining the number of growth layers at the root. Amazing!

Rorqual whales do not possess teeth at all and instead are born with the presence of smaller and softer baleen plates that harden with time. Baleen is a keratin-esque material whales use to filter water through, keeping small fish and krill inside their mouths. Baleen works much like a sieve and the length, color, and size all differ by each whale species. A whale’s baleen will continue to grow from birth until whales reach sexual maturity. More common to arctic water, right whales and bowhead whales possess the longest baleen of all of the rorqual whales group. Reaching lengths of up to 13 feet, bowhead whales are the record holders having approximately 230 to 360 baleen plates on each side of their upper jaw. Conversely, gray whales we commonly see throughout November – May have about 130 to 180 baleen plates on each side of the upper jaw.

Can a baby whale swim right away?

Astonishingly, YES! Unlike humans who require several months before we learn to walk, baby whales or dolphins are born capable of learning to swim on their very first day of life. Most mothers will push their baby to the surface for their first breaths of life and then will continue to stay near them as they learn to move through the water. Many passengers will also ask: “do whales jump out of the water when they are babies?” and the answer is simple, absolutely! Breaching is when a whale is able to lunge its body out of the water. While many scientists and researchers are not certain as to why whales perform this behavior it is thought that they do this for fun. Other scientists believe that it could be a skill learned to knock off unwanted barnacles or parasites. Typically whales learn this behavior through mimicking their mother and through watching her lunge into the air. Whether it is high-flying bottlenose dolphins or humpbacks making a huge splash, we absolutely love getting a glimpse of them breaching in action.

How big are baby whales when they begin to make sounds?

While not born with names such as Nicholas, Michael or Susie, baby dolphins are born with a very specific whistle that other members of the pod will recognize them with for life. These whistles are perfect in utero where mom begins working with her unborn baby so that the newbie knows their sound when they are on their own as early as day one. Unlike odontocetes who use whistles and click and echolocation to communicate with one another, larger baby baleen whales communicate through a series of moans and groans. It is believed by scientists and researchers that baby humpback whales whisper to their mothers, or will make grunts or squeak sounds. This whisper behavior is thought to stay unnoticed from lurking predators like Orca and sharks or other more dominant mating male humpbacks.

When does a baby whale reach adulthood?

Much like humans, whales reach adulthood at different times in their lives. The question, how big are baby whales when they reach sexual maturity depends on their species. Adulthood is more dependent on overall length rather than age. When it comes to the baleen whales, females are always larger than their male counterparts. Larger whales like the blue whale reach sexual maturity when they reach lengths of approximately 75 to 78 feet respectively. Toothed whales are the opposite with males being larger than females. This means that females will reach adulthood more quickly than males. For example, an adult female sperm whale may reach maturity between 7-9 years of age while males can grow up to 20 feet longer than that of a female and will not reach this time until they are at least 10 years or older.

What is the main threat to baby whales?

Predators of every whale species are affected by baby whale size. Avoiding potentially lethal encounters, malnourishment, and temperature all play a role in the first year of a baby whale’s life. We mentioned earlier that different whales are born at different sizes and that the first year of a whale’s life is the most vulnerable for a whale. Carnivorous transient killer whales and various sharks prey upon the unassuming innocence of young whales. Newborns and young calves are especially vulnerable to carnivorous transient killer whales and attacks from various species of sharks. If they can make it through their challenging first year, the chance of survival increases dramatically.

Until then,

Your team at Capt. Dave’s Dolphin and Whale Watching Safari

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