The blue whale is one of nature’s most majestic creatures. They are the largest creatures that have ever lived on our planet, but they can go down from something as simple as colliding with a large ship. These gentle giants are not hunters in the traditional sense, at least, their prey is too small for humans to detect. Like all intelligent mammals, mother blue whales have a long pregnancy. But how long is a blue whale pregnant?
Read on to learn more about blue whales, their pregnancies, and their babies. Then, find out what you can do to help protect this incredibly endangered species.
Background: Blue Whale

Before we dive into blue whale gestation, let’s take a closer look at this incredible animal.
size and appearance
As you might imagine, blue whales are blue. But they are also gray, with pale bellies. Their bodies are long and relatively delicate, with a long tail, dorsal fin, and two flippers that serve as arms. On average, adults grow to be 70-80 feet long and weigh over 200,000 pounds. Blue whales have air holes on the top of their heads. These blowholes eject water columns up to 40 feet above sea level.
habitat and range

Blue whales live in all oceans of the world. They spend their summers near the Earth’s North or South Pole. In winter, blue whales migrate to equatorial waters to feed. Blue whale babies are usually born in late winter or spring and accompany their mothers during migration.
diet and behavior
The largest creatures on Earth eat some of the smallest animals on Earth: krill. Blue whales are known as baleen whales. Their mouths are filled with fine, whisker-like “teeth” that filter their feed. When a blue whale spots a good shoal of krill, it swims towards it at high speed. Just before impact, they open their mouths wide to suck in all the water and krill. They then use their baleen to filter the water and swallow the krill.
How many days is a blue whale pregnant?

Blue whales reproduce every 2-3 years; their pregnancies last about a year.This means a blue whale is pregnant for 12 months or about 365 days. Female blue whales reach sexual maturity at 5 or 15 years of age. Blue whales can have a life expectancy of 80 or 90 years. This means that, during her lifetime, a blue whale mother may give birth to as many as 40 calves!
How many blue whales have one birth?
Blue whales don’t give birth to young like dogs or cats. Instead, these giant marine mammals gave birth to a calf. Blue whale mothers can only give birth to one calf at a time. At birth, the calf weighs about 5,000 pounds and is more than 20 feet long. Within the first six months of life, calves grow to more than 50 feet in length and double their body weight. This is thanks to the mother’s extremely fatty milk, which can contain up to 50 percent fat.
How long can a blue whale live?

Blue whales are believed to live up to 90 years. Without blue whales in captivity, scientists can only study these underwater giants under certain conditions, so no one is certain about their maximum lifespan. However, by counting the layers of wax in the blue whale’s ear canal, the scientists were able to come up with a very close age at death. This is because blue whales are constantly making earwax plugs throughout their lives. Scientists can decipher these layers like growth rings on a tree trunk.
What animal has the longest pregnancy period?

Africa seems to have the longest gestation period of any animal. These incredible pachyderms carry babies for as long as 22 months. That’s more than twice as long as a blue whale is pregnant! Why is it taking so long to be pregnant? Well, scientists think it took a long time for an animal of this size to develop. But more than that, Africa is like one of the smartest animals on Earth, and it takes a long time for all those brain cells to develop.
What whale has the longest pregnancy?
One might think that since blue whales are the largest whales in our oceans, they also have the longest pregnancies. However, you are wrong. In fact, the award for the longest pregnancy of any whale goes to an orca, or killer whale. These iconic black and white hunters breed babies anywhere from 15 to 18 months.
Blue Whale Conservation

Blue whales are currently listed as an endangered species. This is largely due to their near-extinction by commercial whalers in the 19th century. Today, killing blue whales is illegal, but that doesn’t mean they won’t go extinct.
Blue whales are at risk of being killed by boats, entangled in fishing lines and nets, and starved to death from ocean pollution. They are also negatively impacted by ocean noise and climate change.
You can help the blue whale too! If you see a blue whale or any whale in the wild, it is important to keep a safe distance. Never harass or disturb a blue whale, especially if it is a mother or calf.

I am broadly interested in how human activities influence the ability of wildlife to persist in the modified environments that we create.
Specifically, my research investigates how the configuration and composition of landscapes influence the movement and population dynamics of forest birds. Both natural and human-derived fragmenting of habitat can influence where birds settle, how they access the resources they need to survive and reproduce, and these factors in turn affect population demographics. Most recently, I have been studying the ability of individuals to move through and utilize forested areas which have been modified through timber harvest as they seek out resources for the breeding and postfledging phases. As well I am working in collaboration with Parks Canada scientists to examine in the influence of high density moose populations on forest bird communities in Gros Morne National Park. Many of my projects are conducted in collaboration or consultation with representatives of industry and government agencies, seeking to improve the management and sustainability of natural resource extraction.