Big Headed Boneheaded Bowheads
When you imagine a beautiful sea animal, part of the image that comes with it is a dorsal fin, but bowhead whales don’t have one, nor do the narwhal and beluga. In case you’re wondering what in the world a dorsal fin is, it’s a triangular protrusion that seems like it’s floating on water: think JAWS.
But, you see, there are benefits to not having a dorsal fin as it prevents heat loss, reduces surface area, and allows these whales to swim under ice sheets.
The bowhead whale is famous for its size, and even just the measure of its mouth is marveling. Their mouths can be up to twelve feet high, sixteen feet long, and eight feet wide, and their tongue alone weighs a ton. Now that you have a vague image of their mouth, can you imagine their head? It takes up about one third of their body and can be used as a battle ram to smash through ice up to two feet thick. They are one of the largest whale species in the world, second only to the blue whale in size. Their average length is fifty to sixty feet. They can also weigh up to 100 tons (220,462 Ib). On the surface of their head are not one, but two blowholes that can be used to spray water twenty feet high into the air after thirty minutes underwater. Bowhead whales can normally hold their breath for about thirty minutes, but the most they have ever held is forty mins, and they have the ability to dive in between the range of 330 and 850 feet, and the maximum is 370 to 1,584 feet. To give you a bit of deeper information, the Cuvier’s beaked whale, also the leader in this pack, can dive down to 9,816 feet, so our bowhead buddy is actually a pretty shallow diver.
Since the bowhead whale’s environment is in the icy waters of the Arctic, it needs to keep itself warm. So they have a thick layer of blubber to provide heat and energy, and it can be up to around 27.5 inches thick. As mentioned, this whale often uses its powerful skull that is about up to one foot thick to break ice, which creates a breathing hole for them.
But even though they have such a huge size, their food is very small. The massive bowhead whale is huge, and it needs food to keep up. Can you believe that they can eat up to two tons of food every day? And can you believe that they eat about 100 tons each year? That’s amazing! The bowhead whale eats by swimming with their mouths open, and in comes the food. Can you imagine just showing up at the dinner table and opening your mouth? What would your mom say? Their food filters through their baleen plates. Out of all whales, the bowhead whale’s baleen is the longest.
Most of their feeding is during the summer months of the Canadian Arctic.
As mentioned, they eat microscopic plankton, and feed exclusively on marine invertebrates like krill and copepods, so they migrate seasonally to take advantage of food and to also avoid ice entrapment. You can normally find them at the edge of the pack-ice areas. They’ll migrate over very short areas depending on the movement of ice above them. In the winter, where ice is freezing up, they will move north, but in the summer, they move south.
Females typically give birth to one calf every three to four years of a gestation period of about thirteen to fourteen months. Newborns are about thirteen to fourteen feet long and nurse their mother (oops I am sure you are thinking that for some reason the mother sidles up to the baby looking for milk, my bad, it is the other way around) the MOTHER nurses the baby for nine to twelve months. To survive the low temperature of the water, newborns are born with a thick layer of blubber to protect them. And amazingly, calfs are able to swim after thirty minutes they are born. They also typically grow 30 feet during their first year: imagine giving a birthday party to a forty-five foot long infant! Sexual activity normally occurs in pairs of boisterous males and one or two females. Breeding seasons are observed to be around from March to August. Reproduction can begin for a whale at the age between ten to fifteen years old. Conception mostly occurs during March, which is when song activity is at the highest time of the year.
All whales like to sing, for whether it is to communicate with each other, locate food, find each other or even for the males to show off to attract the females during mating season, these bigheaded and boneheaded goliaths love to make music!
An oceanographer from the University of Washington, Dr. Kate Stafford ventured into the dark icy waters of Fram Strait, between the Greenland and Norway islands, and found bowhead whales singing. It was described to sound like they were shrieking like cats, making trumpet-like noises, and low woo woo noises. Scientists say that the bowhead whale sings with two voices: one voice making a low-pitched sound and the other making a high-pitched noise at the same time. I mean if your tongue is as big as a Yugo, it makes sense that two or even three or even 15 voices could come out of it, no?
Bowhead whales are highly vocal, and use low vocal sounds during traveling, feeding seasons, and when socializing with each other. While more intense calls are heard for communicating and navigating, especially during the migration season. During breeding season, bowheads tend to make long, complex variable songs: a type of romantic swooning. During mating season, bowhead whales tend to be singing twenty four hours per day, and they would do this most of the winter for every single year. These calls would be made by males to attract females and show dominance.
A group of scientists and biologists from Suffolk University, Arctic Aquatic Research Division, Fisheries and Oceans Canada, and the Greenland Institute of Natural Resources studied hormones of the dead bodies of bowhead whales killed by the Inuit during a 13-year period. Their research shows that a group of female bowhead whales were likely pregnant for about fourteen months, and they found this by noting fetus size in many dead whales. However, they also found that bowhead whales can be pregnant for up to twenty three months. Why? Well, according to a research team, they found that the bowhead was able to put a pause to their pregnancies, which allowed the mother-to-be to choose a suitable time to birth her baby, with ideal hormone levels. But to research more about reproduction, the group collected baleen samples from bowhead whales that were killed by Inuit hunters in the Greenlandic and Canadian Arctic.during these thirteen years: 1998 to 2011. By studying closely, these samples offered a snapshot of their life, like their hormone levels, and in particular progesterone, estradiol, and corticosterone. Each of those hormones are produced during different times of the pregnancy process. Studying these hormones over time, they discovered that these female whales were pregnant for a period of twenty three months! The research group suggests that baleen females were able to put a nine month pause on their pregnancy, which is why the pregnancy lasted so long. Now, I found this mind-blowing and I’m sure you feel the same way, too. I wish I could tell you more, but additional research will need to be done by this amazing research group. But if the number holds, that would make baleen mammals like bowhead whales have the longest pregnancy duration. The current champions of this are the elephants, with the average pregnancy duration of twenty two months.
Even though the bowhead is such an amazing whale and loved by so many, some populations are currently endangered due to the economic value of their oil, and with their slow swimming speeds, they were once hunted to near extinction. The Inuit still use their oil for cooking and making traditional whale oil lamps. Bowhead whales are normally seen in groups of three or less, though they do get together in larger groups during feeding periods.
There are also legends: an Inuit legend says that the whales were offered to the people for survival, and were not killed needlessly. The legend goes that the special season spring was created, and it was when the ice would crack and mists appear above the sea. That made it easy for the people to capture the whales and the mist blurred the vision so the creator didn’t have to see the killing; thus the whales were treated with great respect. They are the symbol for the people of mankind and nature, and it was also believed that the whale’s spirit would return to the water and be reborn. Sadly, European and American whalers did not have this sort of respect and once almost hunted the whales to extinction.
All this time I have been teaching you about their pregnancy, mating, baleen, songs and more, did I mention about their lifespan? Bowhead whales are considered to be one of the longest living mammals on earth. The average age for bowhead whales is either around two hundred years old or even older than that. Imagine living for that long! How long a bowhead whale can live can depend on their cells and their genetics. Since they are one of the biggest mammals, they have about a thousand times more cells than other animals. Australia’s national science agency estimated that a bowhead whale’s maximum natural lifespan based on genetics is 268 years old.
