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For the Love Of Nature, Art and Bad Humor
A Comic Gallery of Creative Expression in the Pursuit of Knowledge
Manatee
West Indian Manatee, Sea cow, Chubby Mermaid
Trichechus manatus
Sea cow - because they graze all day like a cow.
Manatee - from the Carib word manati meaning breast or udder.
Mermaid - because early sailors heard the word breast and their imaginations did the rest? Too much rum and time at sea?
Regardless of all that sailor confusion, they are gentle
non-mermaid giants, and the ocean's largest herbivore.
Some cool manatee facts:
They don't have earlobes, but they do have ears - tiny
holes located behind their eyes. Inside each ear hole is
an ear bone, and you can determine a manatee's age by
the annual growth rings on those bones. Just like a tree.
Their eyes are tiny too - and they have no eyelashes -
but they do have a nictitating membrane that works
like a built-in protective goggle, letting them
see fairly well underwater.
They have teeth like a shark!
Just kidding. That would be horrifying.
They have conveyor belt-like teeth like a shark - teeth that wear down, fall out, and are continuously replaced by new ones moving in from behind. Sharks do this too, but with sharper teeth. The marching molars are necessary since manatees' teeth can wear quickly from grinding up plants mixed with sand. Gritty green num nums.
Their closest relative is the elephant - but they're also a
little like sloths. Slow-moving, algae-growing, plant-eating, and unable to turn their heads sideways. Manatees
only have six neck vertebrae; all other mammals have seven. Like sloths, they have to turn their whole body
to look behind them. They are awkward but
adorable marine elephant sloth cows.
They look big and blubbery but are mostly
just stomach and intestines.
Gritty green num nums have low nutritional value,
so they have to eat 10-15% of their body weight everyday - that's about 100-150 lbs of seagrass, leaves and algae
for an average 1,000 lb manatee. What a cow!
But since they have very little insulation, they get
cold-stressed easily in water below 68°F.
All that eating generates some internal heat - but not enough to survive cold weather. Which is why they congregate in natural springs or power plant effluents
in the winter, most returning to the same spot each year.
When it warms up, they venture out and can be found as far north as Massachusetts and as far west as Texas.
Mommy manatees are pregnant for an entire year,
then give birth to a 4-foot, 60-pound baby. Ouch. They nurse their gigantic babies for two years before sending them off to someday produce gigantic babies of their own.
They can stay submerged up to 20 minutes, but usually surface every 3–5 minutes while cruising at a leisurely
5 mph. They can push up to 15 mph in short bursts -
twice the speed of an Olympic swimmer - but that kind of effort is mostly reserved for impressing manatee ladies.
Or showing up Olympic swimmers.
When they surface, 90% of the air in their lungs is
replaced. Humans manage about 10%. But lungs
aren't the only place air accumulates in a manatee.
Their plant diet makes them super gassy.
When they let out a toot, they sink a little.
When they hold in a toot, they float up.
They also have solid, marrow-free bones - extra weight that allows them to hang out on the bottom and keep eating more green gas fart fuel. So basically, their buoyancy is controlled by heavy bones, lungs and farts.
Kinda like your uncle.
They have the lowest brain-to-body ratio of any mammal, but they're not stupid. Their gray-to-white matter ratio is higher than even humans' - gray matter being where thinking happens. This gives them excellent long-term memory, which helps them migrate hundreds of miles.
In captivity, they can be trained to do basic tasks,
but aren’t terribly motivated by fish like their
annoyingly enthusiastic dolphin friends.
They have no natural predators but are killed in
alarming numbers every year by boats, fishing nets, fishing line, and seagrass die-offs. Life expectancy is 60 years but these days, few live past 20.
Boat collisions are so common that propeller cuts and scars are the primary identification method when studying manatees. 97% of manatees have them.
They're a threatened species, protected by multiple laws. Harassing one can mean a hefty fine or jail time. Though most harm done to manatees is unintentional.
Boat speeds, fishing litter, fertilizer runoff, and other pollutants are bad for our farty-mermaid friends.
And the rest of the ecosystem.
Manatees are an indicator species - when they're doing well, the environment is doing well, and so are we.
Let’s do better for them and for all of us. Long live the adorable marine elephant sloth cow!
References:
https://myfwc.com/research/manatee/rescue-mortality-response/publication/
https://www.savethemanatee.org/manatees/facts/
https://en.wikipedia.org/wiki/Manatee
https://www.nationalgeographic.com/animals/mammals/facts/manatees
https://myfwc.com/education/wildlife/manatee/facts-and-information/
https://oceantoday.noaa.gov/endoceanmanatees/
https://www.evergladesfoundation.org/post/10-things-you-didn-t-know-about-florida-manatees-and-where-to-see-them?gclid=CjwKCAjw6vyiBhB_EiwAQJRophc6TF3wnkzmJjEk76hAd0rgAYqMJJoYlkEPn2gRHaaeLLGuzGTvORoCFoQQAvD_BwE
Special thanks to Jay Exum, Ph.D. Wildlife Ecology for his expert fact checking!
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