September 26, 2026 • 8 mins
It's a good question. The blue whale is the largest known animal to ever grace the planet (they may be twice as big as Megalodon was! Their tongues are as heavy as elephants!), but they're still mysterious. Learn what science knows (and doesn't know) about blue whales in today's classic episode of BrainStuff, based on this article: https://animals.howstuffworks.com/mammals/blue-whale.htm
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Speaker 1 (00:01):
Welcome to BrainStuff, a production of iHeartRadio.
Speaker 2 (00:06):
Hey, BrainStuff. Lauren Vogelbaum here with another classic episode of
the show for you. In this one, we dip into
the amazing lives of blue whales, which are the biggest
and one of the loudest animals our world has ever known.
Speaker 1 (00:23):
Hey, BrainStuff. Lauren Vogelbaum here.
Speaker 2 (00:25):
Dating back to the days of woolly mammoths, humans have
been obsessed with larger-than-life mammals— And on the aquatic front,
there's no bigger mammal than the blue whale, which is
the largest known animal to ever grace the planet. No
evidence has been found that any other creature, even the
largest of dinosaurs, surpassed the blue whale in size. But wait,
what about the megalodon, the extinct shark species believed to
(00:46):
be the largest fish on the planet, and which you
may recall from the 2018 horror movie The Meg? Well,
scientists guessed that even the biggest megalodon only reached a
mere 58 feet in length, though some argue it was
up to 82 feet. That's 18 up to 25 meters.
By contrast, the largest blue whales clock in at a
little more than 100 feet or 30 meters long, and
(01:06):
on average are between 70 and 90 feet in length.
That's 23 to 27 meters. And their average weight is
approximately 400,000 pounds. That's 181,000 kilograms or about 200 tons. Females,
by the way, tend to be larger than males. The
largest blue whales live in the Southern Ocean near Antarctica.
A blue whale's tongue alone weighs as much as an elephant.
(01:28):
About 100 people could fit in a blue whale's mouth.
A blue whale's heart is the size of a car,
its eye is the size of a basketball, and a
small child could swim through its arteries. The spray from
a blue whale's blowhole is almost as tall as a
three-story building that's about 30 feet or 9 meters high.
These aptly named whales are blue-gray in color with lighter
gray patches that resemble splotches of paint, though they also
(01:51):
go by sulfur-bottom whale due to their yellowish underbelly. The
blue whale is part of the baleen whale family, a
group of toothless whales.
Speaker 1 (01:59):
It has, instead of teeth, plates of thick, coarse.
Speaker 2 (02:01):
Bristles in its mouth that it uses to catch food.
These are called black baleen, or whalebone, and a single
whale might have up to 800 plates of the stuff
in its great mouth. Despite their massive size, blue whales
rely on very tiny two-inch crustaceans known as krill as
their staple meal. But boy, do blue whales eat a
lot of krill. We spoke with Adam Ratner, a marine
(02:24):
scientist with the Marine Mammal Center. He said, given their size,
blue whales rely on vast quantities of food. Using plates
of baleen to filter small zooplankton from the water, they
can consume up to six tons or 20,000 pounds.
Speaker 1 (02:37):
That's over 5,000 kilograms of krill every day.
Speaker 2 (02:40):
In one gulp, the blue whale can take in 125%
of its body weight of water and krill.
Speaker 1 (02:45):
That's half a million calories.
Speaker 2 (02:48):
Despite all the hubbub over their hefty size, not much
is known about blue whales' behaviors and social structures. Ratner said,
We do tend to see blue whales traveling alone or
in small groups. In terms of behavior in the wild,
they don't tend to be very belligerent to each other
or other animals, but rather focused on feeding or migrating.
But again, behavior during breeding season could be very different
(03:09):
and is still in need of more research. But marine
biologists are studying one way that blue whales communicate.
Speaker 1 (03:15):
With each other, sound.
Speaker 2 (03:17):
Ratner said blue whales produce one of the loudest sounds
in the animal kingdom, a low rumble that can be
heard hundreds of miles and even reported to be thousands
of miles away in the ocean.
Speaker 1 (03:27):
Researchers are still unsure of.
Speaker 2 (03:28):
The meaning of the vocalizations, though, with best guesses being
around finding mates or signaling opportunities for mating or feeding.
Along with studying whale behavior, scientists use whale vocalizations to
estimate whale population sizes. When these whale calls are repeated
in a sequence, they become known as songs. They often
repeat sequences vocalized by other blue whales and add riffs
(03:49):
of their own, sort of like whale memes or pop music.
We also spoke with John Kalambokidis, a co-founder of the
nonprofit Cascadia Research and a research biologist who has conducted
extensive studies on the movement of blue whales. He explained,
we've recently discovered these very loud calls are produced only
by males, indicating it plays some role in mating or
(04:09):
in competition with other males. He notes that blue whales
will also form male-female pairs during mating season, with the
female leading the pair. Competition for mates can also get
a little intense, apparently. Kalambodakis said, there's also competition involving
high-speed swimming that occurs when more than one male is involved.
Blue whales can adjust the frequency of their songs by
(04:30):
changing the speed at which they blow air through their
vocal cords. Some researchers think they can do this intentionally,
as they've observed a gradual reduction in the frequency of
blue whale calls over the years, perhaps in reaction to
noisy conditions caused by objects like passing ships. A female
blue whale might give birth to a single baby calf
every two to three years.
Speaker 1 (04:49):
Each pregnancy lasts around 11 months.
Speaker 2 (04:52):
These blue whale babies typically are a whopping 25 feet long,
around eight meters, and weigh 7,000 pounds, or over 3,000 kilograms,
which is heavier than a mid-sized SUV. Ratner said, the
milk from their mothers is so nutritious that the calves
gain 200 pounds, that's 90 kilograms, a day nursing. A
blue whale's average lifespan is 80 to 90 years. However,
(05:13):
their existence is increasingly under threat. Blue whales are currently
listed as endangered under the Endangered Species Act. As commercial
whale hunting took off in the early 1900s, blue whales
dropped from a pre-whaling population of 250,000 to an estimated
10,000 to 25,000 individuals alive presently. Most of the decrease
has been observed in the Southern Hemisphere, where blue whales
(05:34):
were previously the most numerous. We also spoke with Jeff Jacobson,
a marine biologist with the Noyo Center for Marine Science.
He said, for some reason, blue whales were not as
impacted by whaling along the California coast, and we have
at least 2,000 individuals here. the population is still recovering
around Antarctica. He said that whales still remain highly vulnerable
(05:55):
to collisions with ships, perhaps because more krill sometimes appear
in shipping lanes. Other challenges facing the blue whale include
entrapment in fishing gear and climate change affecting the mammals'
food sources. But there are some organizations working to make
habitats safer for blue whales. Ratner says that the Marine
Mammal Center has addressed policies about changing shipping lanes in
San Francisco Bay in order to reduce the likelihood of
(06:16):
boats impacting migrating whales. He also said that, quote, individuals
around the world can make a huge difference by examining
their carbon footprint and working within their communities, neighborhoods, schools
and work to reduce their use of fossil fuels like coal,
oil and natural gas for energy and transportation, as well
as reducing their use of single-use plastics, one of the
most commonly found items of ocean trash that can pose
(06:37):
a threat of entanglement or ingestion for large whales. Like
many marine mammals, blue whales migrate as the seasons change,
but you can find them all over the globe, in
every ocean except the Arctic, and both on coastal shelves
and deeper waters. Ratner explained that the whales typically migrate
toward the north and south poles, heading into cooler waters
in the summer to feast, then back toward the equator
(06:58):
in the winter to breed. But Kalambokidis adds that the
blue whale's migration patterns are slightly more flexible than other
baleen whales, like the gray whale. This is mainly because
blue whales are always in search of food to satisfy
their large appetites, so their movements are geared more toward
finding food sources than adhering to strict migratory patterns. Although
there are a number of distinct blue whale populations, they
(07:19):
can broadly be grouped into those that reside in the
northern hemisphere and those that are found in the southern hemisphere.
One of the larger populations in the northern hemisphere is
the estimated 2,000-some blue whales that feed off the coast
of California and migrate to Costa Rica and Mexico.
Speaker 1 (07:34):
It's somewhat difficult to track them because satellite.
Speaker 2 (07:36):
Tagging that you might use on other marine mammals like
sea lions could cause skin infection in the whales. Scientists
studying whales will often use a more basic photo identification
system to keep track of specific blue whales around the
world because they each have unique markings on their skin
that can be used to keep track of them. And
for some good news, according to the International Union for
Conservation of Nature Red List of Threatened Species, blue whale
(07:59):
numbers have likely gone up in recent decades. So things
seem to be looking up for the blue giant. Today's
episode is based on the article, The Blue Whale, Bigger
Than Megalodon, on HowStuffWorks.com, written by Tara Yarlagada. BrainStuff is
a production of iHeart Podcasts in partnership with HowStuffWorks.com and
(08:22):
is produced by Tyler Klang. For more shows from iHeart Podcasts,
visit the iHeart Radio app, Apple Podcasts, or wherever you
listen to your favorite shows.
Welcome to BrainStuff, a production of iHeartRadio.
Speaker 2 (00:06):
Hey, BrainStuff. Lauren Vogelbaum here with another classic episode of
the show for you. In this one, we dip into
the amazing lives of blue whales, which are the biggest
and one of the loudest animals our world has ever known.
Speaker 1 (00:23):
Hey, BrainStuff. Lauren Vogelbaum here.
Speaker 2 (00:25):
Dating back to the days of woolly mammoths, humans have
been obsessed with larger-than-life mammals— And on the aquatic front,
there's no bigger mammal than the blue whale, which is
the largest known animal to ever grace the planet. No
evidence has been found that any other creature, even the
largest of dinosaurs, surpassed the blue whale in size. But wait,
what about the megalodon, the extinct shark species believed to
(00:46):
be the largest fish on the planet, and which you
may recall from the 2018 horror movie The Meg? Well,
scientists guessed that even the biggest megalodon only reached a
mere 58 feet in length, though some argue it was
up to 82 feet. That's 18 up to 25 meters.
By contrast, the largest blue whales clock in at a
little more than 100 feet or 30 meters long, and
(01:06):
on average are between 70 and 90 feet in length.
That's 23 to 27 meters. And their average weight is
approximately 400,000 pounds. That's 181,000 kilograms or about 200 tons. Females,
by the way, tend to be larger than males. The
largest blue whales live in the Southern Ocean near Antarctica.
A blue whale's tongue alone weighs as much as an elephant.
(01:28):
About 100 people could fit in a blue whale's mouth.
A blue whale's heart is the size of a car,
its eye is the size of a basketball, and a
small child could swim through its arteries. The spray from
a blue whale's blowhole is almost as tall as a
three-story building that's about 30 feet or 9 meters high.
These aptly named whales are blue-gray in color with lighter
gray patches that resemble splotches of paint, though they also
(01:51):
go by sulfur-bottom whale due to their yellowish underbelly. The
blue whale is part of the baleen whale family, a
group of toothless whales.
Speaker 1 (01:59):
It has, instead of teeth, plates of thick, coarse.
Speaker 2 (02:01):
Bristles in its mouth that it uses to catch food.
These are called black baleen, or whalebone, and a single
whale might have up to 800 plates of the stuff
in its great mouth. Despite their massive size, blue whales
rely on very tiny two-inch crustaceans known as krill as
their staple meal. But boy, do blue whales eat a
lot of krill. We spoke with Adam Ratner, a marine
(02:24):
scientist with the Marine Mammal Center. He said, given their size,
blue whales rely on vast quantities of food. Using plates
of baleen to filter small zooplankton from the water, they
can consume up to six tons or 20,000 pounds.
Speaker 1 (02:37):
That's over 5,000 kilograms of krill every day.
Speaker 2 (02:40):
In one gulp, the blue whale can take in 125%
of its body weight of water and krill.
Speaker 1 (02:45):
That's half a million calories.
Speaker 2 (02:48):
Despite all the hubbub over their hefty size, not much
is known about blue whales' behaviors and social structures. Ratner said,
We do tend to see blue whales traveling alone or
in small groups. In terms of behavior in the wild,
they don't tend to be very belligerent to each other
or other animals, but rather focused on feeding or migrating.
But again, behavior during breeding season could be very different
(03:09):
and is still in need of more research. But marine
biologists are studying one way that blue whales communicate.
Speaker 1 (03:15):
With each other, sound.
Speaker 2 (03:17):
Ratner said blue whales produce one of the loudest sounds
in the animal kingdom, a low rumble that can be
heard hundreds of miles and even reported to be thousands
of miles away in the ocean.
Speaker 1 (03:27):
Researchers are still unsure of.
Speaker 2 (03:28):
The meaning of the vocalizations, though, with best guesses being
around finding mates or signaling opportunities for mating or feeding.
Along with studying whale behavior, scientists use whale vocalizations to
estimate whale population sizes. When these whale calls are repeated
in a sequence, they become known as songs. They often
repeat sequences vocalized by other blue whales and add riffs
(03:49):
of their own, sort of like whale memes or pop music.
We also spoke with John Kalambokidis, a co-founder of the
nonprofit Cascadia Research and a research biologist who has conducted
extensive studies on the movement of blue whales. He explained,
we've recently discovered these very loud calls are produced only
by males, indicating it plays some role in mating or
(04:09):
in competition with other males. He notes that blue whales
will also form male-female pairs during mating season, with the
female leading the pair. Competition for mates can also get
a little intense, apparently. Kalambodakis said, there's also competition involving
high-speed swimming that occurs when more than one male is involved.
Blue whales can adjust the frequency of their songs by
(04:30):
changing the speed at which they blow air through their
vocal cords. Some researchers think they can do this intentionally,
as they've observed a gradual reduction in the frequency of
blue whale calls over the years, perhaps in reaction to
noisy conditions caused by objects like passing ships. A female
blue whale might give birth to a single baby calf
every two to three years.
Speaker 1 (04:49):
Each pregnancy lasts around 11 months.
Speaker 2 (04:52):
These blue whale babies typically are a whopping 25 feet long,
around eight meters, and weigh 7,000 pounds, or over 3,000 kilograms,
which is heavier than a mid-sized SUV. Ratner said, the
milk from their mothers is so nutritious that the calves
gain 200 pounds, that's 90 kilograms, a day nursing. A
blue whale's average lifespan is 80 to 90 years. However,
(05:13):
their existence is increasingly under threat. Blue whales are currently
listed as endangered under the Endangered Species Act. As commercial
whale hunting took off in the early 1900s, blue whales
dropped from a pre-whaling population of 250,000 to an estimated
10,000 to 25,000 individuals alive presently. Most of the decrease
has been observed in the Southern Hemisphere, where blue whales
(05:34):
were previously the most numerous. We also spoke with Jeff Jacobson,
a marine biologist with the Noyo Center for Marine Science.
He said, for some reason, blue whales were not as
impacted by whaling along the California coast, and we have
at least 2,000 individuals here. the population is still recovering
around Antarctica. He said that whales still remain highly vulnerable
(05:55):
to collisions with ships, perhaps because more krill sometimes appear
in shipping lanes. Other challenges facing the blue whale include
entrapment in fishing gear and climate change affecting the mammals'
food sources. But there are some organizations working to make
habitats safer for blue whales. Ratner says that the Marine
Mammal Center has addressed policies about changing shipping lanes in
San Francisco Bay in order to reduce the likelihood of
(06:16):
boats impacting migrating whales. He also said that, quote, individuals
around the world can make a huge difference by examining
their carbon footprint and working within their communities, neighborhoods, schools
and work to reduce their use of fossil fuels like coal,
oil and natural gas for energy and transportation, as well
as reducing their use of single-use plastics, one of the
most commonly found items of ocean trash that can pose
(06:37):
a threat of entanglement or ingestion for large whales. Like
many marine mammals, blue whales migrate as the seasons change,
but you can find them all over the globe, in
every ocean except the Arctic, and both on coastal shelves
and deeper waters. Ratner explained that the whales typically migrate
toward the north and south poles, heading into cooler waters
in the summer to feast, then back toward the equator
(06:58):
in the winter to breed. But Kalambokidis adds that the
blue whale's migration patterns are slightly more flexible than other
baleen whales, like the gray whale. This is mainly because
blue whales are always in search of food to satisfy
their large appetites, so their movements are geared more toward
finding food sources than adhering to strict migratory patterns. Although
there are a number of distinct blue whale populations, they
(07:19):
can broadly be grouped into those that reside in the
northern hemisphere and those that are found in the southern hemisphere.
One of the larger populations in the northern hemisphere is
the estimated 2,000-some blue whales that feed off the coast
of California and migrate to Costa Rica and Mexico.
Speaker 1 (07:34):
It's somewhat difficult to track them because satellite.
Speaker 2 (07:36):
Tagging that you might use on other marine mammals like
sea lions could cause skin infection in the whales. Scientists
studying whales will often use a more basic photo identification
system to keep track of specific blue whales around the
world because they each have unique markings on their skin
that can be used to keep track of them. And
for some good news, according to the International Union for
Conservation of Nature Red List of Threatened Species, blue whale
(07:59):
numbers have likely gone up in recent decades. So things
seem to be looking up for the blue giant. Today's
episode is based on the article, The Blue Whale, Bigger
Than Megalodon, on HowStuffWorks.com, written by Tara Yarlagada. BrainStuff is
a production of iHeart Podcasts in partnership with HowStuffWorks.com and
(08:22):
is produced by Tyler Klang. For more shows from iHeart Podcasts,
visit the iHeart Radio app, Apple Podcasts, or wherever you
listen to your favorite shows.
BrainStuff News
Host
Lauren Vogelbaum
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