This episode is sponsored by Wren, a  website with a monthly subscription that helps fund projects to combat the climate crisis.

Click the link in the description to learn  more about how you can make a monthly contribution to support projects  like rainforest protection programs. [♪ INTRO]   If you’ve spent any time in Florida  in the USA, you may have been lucky enough to encounter one of  their most famous locals.   And it’s not the Florida Man.  It’s the Florida manatee.   These slow-moving sea cows face a number of human-caused threats, from boat  collisions to habitat loss.   One of the most surprising  threats is also caused by humans: the closing of aging power plants.   The good news is, since we created  this situation in the first place, we should be able to find a way out of it.   The Florida manatee is the most northerly  subspecies of West Indian manatee. It’s found almost exclusively  in the southeastern USA.

Though commonly called “sea cows,” they’re  more closely related to elephants.   You’ll find these amazing marine  mammals hanging out in shallow coastal waters, from seagrass  meadows to salt marshes.   And they’ve adapted to some  pretty warm temperatures.   That might be surprising to hear, given  that they look pretty, uh... insulated. But that’s not actually the case. Combine that with their low metabolic rates, and they’re just not great  at keeping themselves warm.   These gentle giants can actually die if the water stays below eighteen to twenty  degrees Celsius for long stretches.

When temperatures reach as  low as ten to twelve degrees, they can succumb to the cold in only a few days. And we might think of Florida as pretty balmy, but even the southernmost tip can hit  these temperatures during cold winters.   Although they don’t come off as  the most athletic of species, manatees can actually cover significant  distances during seasonal migrations. Some individuals travel as far as 830 kilometers between their summer and winter hangouts.   However, instead of taking  on longer migrations, some populations of manatees seek out refuge  in warm water to survive cold spells.

That is, pockets of warm water  in an otherwise cooler area.   These could be naturally occurring  springs or passive thermal basins, which are heated by the sun, ground  water, or other natural phenomena.   Or they can be the discharged water  from power plant cooling systems. And these unintentional man-made refuges  are really popular with manatees.   A 2004 report found that of the  14 warm water refuges in northern and central Florida, 10 were  outfalls from power plants. These power plants attract around  60% of all of Florida’s manatees.   The worrying thing is, all of these  manatee-attracting power plants are decades old, and are either close to  retirement or have shut down already.   And these days, restrictions on thermal pollution prohibit new power plants from  discharging notably warmer waters.

This means once these old  plants are out of commission, most of the warm water refuges the  manatees currently depend on will be too.   What’s most distressing is that, while  other populations take on longer winter migrations to find safety from the cold,  the manatees who have come to depend on a particular power plant don’t  seem to shift their habits.   Calves learn from their moms what refuges to use, and typically stick with the  same site their whole lives.   And if past power plant  retirements are anything to go by, the manatees will keep coming  back after the warm water is gone, even if it means succumbing to the cold.   On top of that, the natural  springs that manatees depend on may also be disappearing thanks  to climate change and human overuse.   But there are ways we can help  wean manatees off of power plants. One possible way is by literally  erecting sea cow fencing. By shifting these barriers further  away from the plant over time, the manatees might be  encouraged to find new naturally warmed water refuges elsewhere.

Protecting the waters they  currently use is also key, to ensure there aren’t further losses of natural warm winter hangouts beyond the power plants. Another solution could be to make  other warm water areas more accessible, through better management of natural  springs and removing barriers that may impede larger numbers of manatees from using them. There’s even talk of making new human-made  warm water refuges that aren’t tied to another industry, so there isn’t the  same risk of them aging out of service.

There is still a lot of work that needs  to be done to determine which of these options are the most beneficial  to the manatees and ensure they don’t harm any other  species in the meantime.   The good news is with multiple options to explore, there’s hope for protecting  these much-loved sea cows from meeting a frigid demise. Thank you for watching this episode of SciShow! And thank you to today’s sponsor, Wren.

Wren is a website with a monthly subscription that helps to fund projects to  combat the climate crisis. Wren searches the globe for projects  that have the biggest potential, like protecting rainforests and planting trees. And these projects wouldn’t be  possible without your support.

Over the long term, we need  governments to fund these projects, but we can start by crowdfunding them. And we’ve partnered with Wren  to protect an extra ten acres of rainforest for the first 100 people who  sign up using our link in the description. You can also check out more about their approach and what projects they are currently funding.

Thanks again for watching. [♪ OUTRO]