A Giant Extinct Sea Cow
Summary
TLDRThe story of Steller's sea cow, a massive marine mammal related to dugongs and manatees, serves as a poignant lesson in conservation. First discovered in 1741, these gentle giants, adapted to cold waters with unique anatomical features, were driven to extinction within 30 years due to overhunting by fur traders. Their demise marks a tragic milestone in human history, highlighting the urgent need for conservation to prevent future losses of such unique species.
Takeaways
- π Steller's sea cow, scientifically known as Hydrodamalis gigas, was a massive marine mammal, reaching up to 9 meters in length and weighing around 10 tonnes.
- π First discovered in 1741 by German zoologist Georg Wilhelm Steller, the species was found in the sub-Arctic waters around Bering Island.
- π« Extinct within 30 years of its discovery, it's considered the first marine mammal to be driven to extinction by human actions.
- π Steller's sea cow was adapted to cold waters, with a large body size and thick blubber to reduce heat loss, unlike its tropical relatives.
- πΏ The species had unique feeding adaptations, using keratinous pads instead of teeth and bristles on their snouts to consume kelp and algae.
- π₯ They were social creatures, living in family units and exhibiting behaviors like monogamy and altruism, such as protecting their young and assisting injured members.
- πͺ Overhunting by Russian fur traders, who used the sea cows for food and oil, was the primary cause of their extinction.
- πΎ The habitat shared with sea otters, which were hunted for their fur, indirectly contributed to the sea cow's decline by disrupting the ecosystem.
- π The species' inability to fully submerge and their reliance on shallow coastal waters may have made them more vulnerable to hunting.
- β³ Despite the extinction date being estimated around 1768, there were unconfirmed sightings reported in later centuries, emphasizing the tragedy of their loss.
Q & A
What is the significance of Steller's sea cow story in terms of conservation?
-Steller's sea cow story is significant as it serves as a cautionary tale highlighting the devastating effects humans can have on marine life and the importance of conservation efforts to prevent such extinctions in the future.
How large was Steller's sea cow and what did it weigh?
-Steller's sea cow was approximately eight to nine meters in length and weighed around 11 tonnes.
When was Steller's sea cow first discovered and by whom?
-Steller's sea cow was first encountered by a scientist in 1741, and it was named after the German zoologist Georg Wilhelm Steller.
How are Steller's sea cow related to modern marine mammals?
-Steller's sea cow, technically named Hydrodamalis gigas, is related to dugongs and manatees and is classified as a sirenian.
What adaptations did Steller's sea cow have to survive in colder sub-Arctic waters?
-Steller's sea cow adapted to colder sub-Arctic waters by growing to enormous sizes, developing thick blubber, and having a unique skin texture that was bulk-like and rough along the sides but smooth on the back.
How did Steller's sea cow feed and what did its feeding adaptations include?
-Steller's sea cow primarily fed on kelp and algae. It lacked teeth as an adult but had keratinous pads in its mouth to grind food, and interlacing white bristles on its snout to slice and grasp kelp and seaweeds.
What were the physical characteristics of Steller's sea cow's limbs?
-Steller's sea cow's limbs were heavily modified, described as short and hooked, and did not have any phalanges. The skin on the limbs was thick, aiding in various activities such as pulling, swimming, and clasping.
How did Steller's sea cow differ from manatees and dugongs in terms of buoyancy control?
-While manatees and dugongs can control their buoyancy, Steller's sea cow was reportedly unable to fully submerge, possibly due to its larger size, more blubber, and increased lung and intestine volume.
What social behaviors were observed in Steller's sea cow?
-Steller's sea cow was gregarious, living in small family units and gathering into large groups to feed. They were also monogamous and showed evidence of altruistic behavior, such as protecting their offspring and assisting wounded individuals.
What were the circumstances that led to the extinction of Steller's sea cow?
-The extinction of Steller's sea cow was primarily due to overhunting by Russian fur traders who used the sea cows for food, blubber, and oil. The already small population was further threatened by habitat changes and a decrease in their primary food source, kelp, due to an increase in sea urchin populations.
What is the estimated extinction date of Steller's sea cow and what evidence supports this?
-The estimated extinction date of Steller's sea cow is around 1768, based on reports of fewer sightings and eventual absence of the species. This was confirmed by a German naturalist in the 1800s.
Outlines
π³ The Tragic Extinction of Steller's Sea Cow
Steller's sea cow, scientifically known as Hydrodamalis gigas, was a unique marine mammal that lived in sub-Arctic waters. It was first documented by German zoologist Georg Wilhelm Steller in 1741. The species was remarkable for its size, reaching up to 9 meters in length and weighing 10 tonnes. It was related to dugongs and manatees, but had adapted to colder waters, which led to significant anatomical differences. These included a larger body size to reduce heat loss, thick blubber, and a unique skin texture. The sea cow had no teeth as an adult, using keratinous pads to grind food, and had specialized bristles for feeding on kelp and algae. Despite being social creatures that lived in family units, their peaceful nature and unique adaptations were not enough to save them from extinction, which occurred within 30 years of their discovery due to human actions.
π¦ The Downfall of Steller's Sea Cow and Lessons for Conservation
The extinction of Steller's sea cow was largely due to overhunting by Russian fur traders who sought food during their voyages. The sea cows were an easy target due to their large size and the nutritional value of their meat and blubber. The species was already vulnerable with a small population, and the hunting pressure led to their rapid decline. By 1768, the species was considered extinct. The loss of Steller's sea cow serves as a cautionary tale about the impact of human activities on marine life and the importance of conservation efforts. It highlights the need for understanding and protecting marine species to prevent future extinctions. The video also touches on the potential role of native hunting and ecological changes in the sea cow's decline, emphasizing the complex factors that can lead to extinction.
Mindmap
Keywords
π‘Steller's sea cow
π‘Extinction
π‘Adaptation
π‘Buoyancy control
π‘Altristic behavior
π‘Conservation efforts
π‘Sub-Arctic waters
π‘Blubber
π‘Kelp and algae
π‘Fur traders
Highlights
Steller's sea cow is an important cautionary tale for understanding human impact on Earth's biodiversity and the importance of conservation efforts.
The Steller's sea cow, or Hydrodamalis gigas, was an enormous marine mammal, reaching up to 9 meters in length and weighing 11 tonnes.
First encountered by scientist Georg Wilhelm Steller in 1741, the species went extinct in less than 30 years, marking a significant event in modern human history.
Steller's sea cow is related to dugongs and manatees, classified as a sirenian, but adapted to colder sub-Arctic waters.
The species' large size, up to 10 meters, was an adaptation to reduce heat loss in cold waters, similar to some whale species.
Thick blubber, up to 10 centimeters, and a unique, rough skin texture were adaptations to the cold, protecting against ice and rock.
Steller's sea cow had no teeth as adults, using keratinous pads to grind food, and had interlacing white bristles for feeding on kelp and algae.
The limbs of Hydrodamalis gigas were short, hooked, and thick-skinned, aiding in movement, feeding, and mating behaviors.
Unlike modern sirenians, Steller's sea cow could not control its buoyancy and was unable to fully submerge.
The species lived in small family units and exhibited social behaviors, including monogamy and protective parenting.
There are accounts of altruistic behavior in Steller's sea cow, with individuals assisting wounded companions.
The sea cow's extinction is linked to overhunting by Russian fur traders who used them for food and oil, as well as habitat changes.
The hunting of sea otters, a natural predator of sea urchins, may have indirectly contributed to the sea cow's food scarcity and extinction.
The last confirmed sighting of Steller's sea cow was in 1768, but there are unverified claims of sightings into the 20th century.
The extinction of Steller's sea cow serves as a lesson in the consequences of human actions on marine life and the urgent need for conservation.
The story of Steller's sea cow emphasizes the importance of understanding and preventing the extinction of unique marine species.
Transcripts
the story of Steller's sea cow is an
important one to know it's a cautionary
tale that everyone should be aware of to
truly appreciate the devastating effects
that humans can have on the life of this
planet and the relevance of conservation
efforts there once existed an incredibly
remarkable creature quite unlike
anything alive today and we were so
close to seeing them in the flesh
approaching eight to nine meters in
length and 11 tonnes in weight this
organism was first encountered by a
scientist in the year 17 41 and then in
less than 30 years it was completely
extinct the death of stellar sea cow
seems to have therefore been the first
instance in modern human history that a
marine mammal fell prey to the direct
actions of our own species there really
is nothing like these animals left
around today stellar sea cow technically
named Hydra demolish gigas is related to
the dugong and manatees and are thus
classified as Cyrenians along with these
modern taxa being placed within the
dugong add a family but these extinct
sea cows had adapted to some very
different habitats and this had led to a
pretty different Anatomy evolving
instead of inhabiting warm waters around
the tropics like extant Cyrenians do
hydro Tomales had spread into much
colder sub Arctic waters further north
and therefore some novel changes
occurred in the species to make them
better suited to these areas most
obviously the creatures got enormous
this would probably have been in order
to reduce the surface area to volume
ratio of the animal's body and as a
result reduced the amount of heat loss
to the surroundings cold waters the huge
sizes of almost 10 meters long means
that Steller's sea cow would actually
have been one of the biggest mammals
alive at a time rivaling some whales in
its dimensions also like whales Hydra
domalis had very thick blubber
underneath its skin apparently getting
to around 10 centimeters thick in
certain regions another adaptation to
reducing heat loss the skin of the
organism was reported to have been quite
unique to being bulk like and rough
along the sides but smooth on the back
with a mostly black brown coloration and
sometimes a few white patches
this unusual Ruffins texture is
suggested to have protected the animals
from cuts and scrapes due to sharp bits
of ice and rock as they swam in their
shallow water habitats hydro Tomales had
some pretty interesting feeding
adaptations as they mostly ate kelp and
algae the Cyrenians completely lacked
teeth as adults but instead used to
keratinous pads one on the roof of its
mouth and one at the bottom to grind up
their food in addition to these pads the
creatures possessed interlacing white
bristles on the front of their downtown
snouts which apparently were used in
slicing up and grasping the kelp and sea
weeds they were feeding on bristles were
also present on the insides of their
four limbs and the four limbs themselves
were pretty heavily modified structures
compared to those seen and living
Cyrenians they did not have any
phalanges four finger bones and were
described by people who witnessed them
as being short and hooked allowing for
many uses of the limbs such as pulling
the creatures along in shallow water
swimming picking up food and clasping
during mating the skin was also very
thick on the limbs aiding in these
activities another way that Hydra
demolish differed from the manatees and
dugongs
is in its buoyancy control extent
Cyrenians are capable of controlling
their buoyancy
however Steller's sea cow was reportedly
unable to even a fully submerge
underneath the water's surface this has
been suggested to be due to the larger
size of this species which resulted in a
lot more blubber and an increase in lung
and intestine volume these animals were
gregarious creatures living in small
family units of a bull cow and calf and
gathering into large groups to feed they
were also apparently monogamous and
would protect their offspring when
feeding by staying behind them and other
sites witnesses reported that Hydra
Tomales actually showed evidence of
altruistic behavior as in one case where
a member of a grazing herd was shot by a
harpoon other sea cows gathered around
and attempted to assist the wounded
individual then there was also the story
of a female sea cow being caught and her
bull partner following her and ramming
the boat she was taken on before waiting
for three days near the beach where she
was brought and killed so seeing how
unique this species was and how
seemingly peaceful they were it makes
their loss all the more
but how exactly did this occur how were
they even discovered in the first place
well in 1741 a German zoologist called
Georg Wilhelm Stella was onboard a ship
that became wrecked on Bering Island
staying on the island for about a year
Stella was able to research and document
the animals that lived there including
the sea cows that would be named after
him most of the information we currently
have about this species is thanks to the
observations made by stella including
details of anatomy that were gained from
individuals caught and cut up by the
sailors however despite the significance
of the discovery of a giant Cyrenian
living in sub arctic waters in the
bering sea around the commander and
Aleutian Islands this did not stop what
happens just 27 years later the sea cows
were in a very unfortunate situation
since they shared their habitat with
large populations of sea otters which
were the target of Russian fur traders
at this time in the 1700s fur was
becoming increasingly valuable and so
furry animals became highly sought after
the problem for Steller's sea cow came
when the traders needed food to keep
them going along the route between
Russia and America and the large bodies
of Hydra Tomales with a thick blubber
and masses of meat proved to be the
perfect prey apparently the meat of
these animals tasted similar to beef and
the blubber was tasty too in addition to
being useful in cooking and as lamp oil
it also now seems as though the sea cows
were already under threat from when
Stella first documented them with a very
small population and this hunting
pressure from humans pushed them over
the edge and into extinction as the
hunting continued the population grows
smaller and smaller until natural ists
concluded that the species must have
completely disappeared by 1768 there is
fossil evidence that indicates the
previous range of the genus Hydra
domalis will spread much further along
the coast of Japan and over to the North
American coast so the population
inhabiting the Bering Sea appears to
have been a radek's population in danger
of dying out anyway as they had already
undergone local extinctions in other
regions it's also possible that
Europeans travelling between Russia and
America may not have been the only ones
involved in the sea cow extinct
with natives of the Aleutian Islands and
the Siberian Yupik people potentially
having preyed on the species in the past
reducing their populations before their
final extinction the death of this
species has also been proposed to have
been linked to the hunting of otters in
another way too
when Aboriginal peoples went after the
sea otters and their populations
decreased as a result sea urchin
populations would have risen since
otters feed on them and control their
numbers sea urchins are capable of
significantly depleting supplies of kelp
the primary food source of stellar sea
cow and so with fewer otters about Hydra
da Morris was also facing a shortage of
food the hunting by sailors would
certainly have been the final straw in
their demise though and by the time
anyone had realized that the sea cows
were becoming rarer and rarer it was too
late for them the 1768 extinction date
was given by a German naturalist in the
1800's based on reports of fewer
sightings of the animals and eventual
reports of their absence there are
actually a few claimed sightings of the
species from after 1768 into the 1800s
and even supposedly from the 1900s the
20th century reports are most likely
misinterpreted sightings of other
animals such as elephant seals and would
be impossible to properly verify anyway
the earlier reports though could
possibly imply that the sea cows had
just moved away from land and into
deeper waters by 1768
before then succumbing to the
difficulties brought about by a new
habitat they weren't as suited to
whatever the exact extinction date was
there have not been any confirmed
sightings of hydro domalis for many
years our species undoubtedly has a lot
to learn from the loss of these animals
this was the first time in the modern
history of humanity that we were
responsible for the total extinction of
a marine mammal it would not be the last
time this occurred though hopefully
something like this never has to happen
again it's interesting to consider what
the sailors might have been thinking
about the fewer and fewer sightings of
the sea cows at a time when extinction
was not well understood or even thought
to be possible at all
so I think it's important to know how
close we came to being able to see these
fascinating animals with our own eyes
only for the wastefulness and lack of
understanding of humanity to rob us of
this opportunity these creatures were so
unique really unlike anything else that
lives on this planet right now and it's
truly heartbreaking to think that we've
lost them forever it would be even worse
to think that more unique species of
incredible marine mammals could one day
disappear to and I hope future
generations of humans will not be
looking back on species of whales and
pinnipeds and making videos about how
they wish they could have seen those
recently extinct animals anyway I hope
you enjoyed this video and perhaps now
have a greater appreciation of the need
for effective conservation efforts in
order to avoid any more disasters like
this one if you would like to learn more
about our world its history and the
wonderful wife this surrounds us all
please feel free to subscribe to the
channel if you think we deserve it and
if you would like to see more from us
[Music]
you
Browse More Related Video
Facts: The Dugong
The Greenland Shark - World's Oldest Shark | 500+ Years Old Legendary Shark | Dr. Binocs Show
These Crabs Have Been Crawling Before the Dinosaurs
Biodiversity and Evolution | Population Distribution | Causes of Extinction
Why is biodiversity important to me?
Endangered species and Extinct species | Endangered species | Extinct species | Info Biodiversity
5.0 / 5 (0 votes)