Manatee Assessments | JONATHAN BIRD’S BLUE WORLD


Coming up, Jonathan goes to Florida to join
the manatee assessment team for a day doing checkups on manatees! Welcome to Jonathan Bird’s Blue World! The West Indian manatee is a marine mammal
that lives in the shallow coastal ocean around Florida and the Caribbean sea. As a mammal, it has to surface to breathe
just like dolphins and whales. But unlike dolphins and whales, the manatee
eats only plants, making it the only completely herbivorous marine mammal. Because they are slow and completely harmless,
manatees were hunted extensively in the past, and the population has been diminished by
pollution, encroachment on their habitat and even accidents with boats. Most of the time, manatees are solitary animals,
keeping to themselves. It’s rare to encounter more than one. But in Florida, at the northern end of their
range, the water can get pretty chilly in the middle of winter, and the manatees swim
up rivers to reach warm water springs, where they wait out the cold weather. At Three Sisters Spring in Crystal River Florida,
hundreds of manatees gather for protection. And since they have been protected by law
for more than 40 years, their numbers are finally growing. Waiting out the cold weather isn’t very
exciting. With very little to eat here, and with naturally
anti-social personalities, the manatees mostly just rest in the shallow water. Algae grows on their backs, providing a buffet
for schools of fish. These winter aggregations of manatees provide
the perfect opportunity for biologists to study the population. Back in the first season of Blue World, I
met Dr. Bob Bonde, one of the world’s top manatee experts, as he was performing in-water
manatee assessments to gauge the health of the animals in Crystal River as part of the
US Geological Survey Sirenia Project. Now, more than ten years later, manatees have
made a huge comeback in Florida, and the USGS is still doing health assessments once a year,
but the process has grown to a bigger operation. With the cooperation of dozens of state agencies
and volunteers from institutions all over the state, Dr. Bonde is now running quite
an operation. It’s really important that we get a glimpse
of what they are doing and how they’re resolving their issues in the environment. And we do that through these health assessments. The good news is, they look pretty good up
to this point. What we expect is…this population has grown. When we started with about 100 manatees 20,
40 years ago, now we’re up to over 1,000 in this county. Is there enough carrying capacity out there? Is there enough food? Is there enough warm water sanctuary for them
to persist and survive and carry on? These days, it takes a lot of help to conduct
the assessments. Dr. Bonde gives an introduction to more than
100 volunteers who are about to have a very long day. The process begins by setting a net on a busy
section of Crystal River, where dozens of manatees swim by every hour. Soon a manatee swims into the net, and the
volunteers have to gently pull him to shore. Of course the manatee is scared, having no
way of knowing that no harm will come to him. There is no question that people get wet during
this process! Next, the volunteers lift the manatee using a sling,
and carry it to a waiting boat. It’s a special manatee rescue boat designed
specifically with a removable transom and open stern to allow getting manatees in and
out. They ferry the animal just a few hundred yards
to a place where there is a little more space to work. Then they carry the manatee into a nice warm
tent. A team of veterinarians descend to check the
manatee’s health. They take its temperature. They use ultrasound to measure the thickness
of the fat layer. A healthy manatee has a good thick layer of
fat to keep it warm, but animals that are not getting enough to eat will have a thinner
layer, and this is a good indication of the health of not only the individual manatee
but also the entire manatee population. They also measure the manatee. And they listen to its lungs. I watch with interest and try to stay out
of the way. They do their best to keep the animal comfortable. Dr. Bonde helps keep the whole operation running
smoothly. Meanwhile the manatee is moved to a giant
scale. He is calm, but maybe a little apprehensive. Using a winch, they lift the manatee to get
his weight. Although a typical manatee weighs around 1,000
pounds, a really big one is too heavy for this scale, which has a 2,000 pound limit! Then, having been out of the water for only
half an hour, he is carried back to the boat. They take him out into the middle of the river
and let him go, none the worse for wear, though perhaps with a good alien abduction story
for his buddies. Over the course of the weekend, they capture,
evaluate and release 18 manatees! The next day, I stop in at the USGS office
to catch up with Dr. Bonde’s wife Cathy Beck, who is in charge of the manatee photo
ID system that has been used to track individual manatees for more than 40 years. When we started this Photo ID database, and
started the research on manatees in the late ‘70s, the estimated population was less
than 1,000. And they had just been listed both under the
marine mammal protection act and the endangered species act. Since then, the population has just grown
tremendously. Survival rate has gone up. Sadly, most manatees have scars from old injuries,
often from encounters with boats. But these unique scars can be used like fingerprints
to identify individual manatees. Usually, by the time they are sub adults,
usually by the time they are adults for sure, they have some kind of feature that we can
use for identification. And every one of these is a different… …is a different code, right. So… I don’t see it on your picture but… Yeah, I didn’t update the sketch. But this long, skinny one there, what’s
that? That’s the…sorry this is the SLB, so this
is the scar on the left, mid-body. B is “mid body.” One large gray line. When we’re in the field and take pictures,
we come back and we don’t know who it is, so I’m entering codes to search, to see
if I can match it to a known animal, and that’s how we bring it all together. Like if I put that in as a scar, left side,
mid-body, one large white, or gray line, it was a gray line, right? One large gray line. And let’s do all areas, okay. So I have 141 possibilities which is a whole
lot better than 4369! Right? So it helps a lot to have codes for all of
our animals in the database, and then we code the animal. This is a crazy amount of work! It is a lot of work! It is a lot of work! The benefit of a Photo ID system is that animals
can be tracked over large periods of time. They have learned a lot of about manatees
with this system. For example, three manatees in the database
have been known to swim all the way to Cape Cod in Massachusetts, a 3,000 mile round trip! One female has given birth to 13 calves over
the 40 years she has been in the database. They have learned how fast manatees grow,
how far they swim, and all kinds of useful information, which has been used to help protect
the species over the years. The annual manatee assessment is an important
part of the protection plan because a small random sampling of animals ought to reveal
a lot about the general health of the population. And what they are finding out is that manatees
are definitely on the road to recovery. In 40 years, the population of manatees in
Florida has risen from 1,000 to 6,000. That is certainly not a full recovery, but
it shows that the protections are working and the manatee is making a slow comeback. Which is how manatees do most everything…in
the Blue World.

100 thoughts on “Manatee Assessments | JONATHAN BIRD’S BLUE WORLD

  1. Hi and wow ! These Manatees are so wonderful animals 🙂 They are also on my bucket list ! Kindly regards and thumbs up for your video !

  2. There was news that in Australia they found a dead great white in an abandoned wildlife park. Can you go there? I wanna know about that dead shark more!

  3. Hey Jonathan… Each time you come up with the same animal, there is something new to learn… I really enjoyed it…?

  4. We had a manatee swim right up to us on the beach down on Sanibel Island last year. It hung around for about 10 minutes as if to say hello humans.

  5. Very interesting and I learned many things today and Manatee are increasing too. We still have many endangered species to watch and needs to understand. Thank you.

  6. if the weighing scale is not 'big' enough for the manatee, maybe use a big tub with water and see how much water it displaces and maybe get a good measurement that way?

  7. ever since I was a child, and saw a National Geographic special on the Manatees, it has been my dream since then. thank you for sharing this video of these amazing creatures.

  8. So glad I have been able to dive with these gentle giants. Would like to say thanks to all of the people helping to save them.

  9. If you’re ever in Florida again, I’d recommend checking out the South Florida Museum. They have a manatee rehabilitation program, and once housed the oldest captive manatee before he died in 2017.

  10. Dive on mariana trench. They think that Megalodon is living in mariana trench. And btw these creatures are so cute i enjoyed watching it

  11. Hey Jonathan, wasn’t sure where/how to reach out directly. But have been one of your highest contributing patreons for a while now but haven’t received the ‘benefits’ for my level. Let me know who/where to reach out to know more (I.e. is it only after a certain amount of time? Or are those benefits no longer part of the program, etc.).

  12. So good to see the difference between your earlier, less than happy, vid on manatees & this newer, more hopeful installment!!! If we can do this for every creature then we may be able to fix much of the damage we've done to this world!!!

  13. Manatees are so cool! It’s so sad to hear that people used to take advantage of manatees and kill them for what resources they give.

  14. Been diving there since true early 2000’s. Crystal River has changed a lot in that time. For good and bad. Not nearly as beautiful as before.

  15. I am curious to how the manatee population is growing and staying healthy with 500-800 manatee deaths (15-20% of total population) in most years, combined with slow sexual maturity and low gestation periods. They really are amazing and should not be downgraded in the Endangered Species Act.

  16. The most beautiful creatures ? in the world, right up there with whales, sea lions, seals, dolphins .my favorites!!! Water Angels!!

  17. "We people are such nice creatures".

    But at last we have people who want to help.

    Mediterian monk seal is he still alive I mean is he extinct.
    I know he aparently extinct here in Adriatic sea.
    He did apear I think 3 years ago.

  18. You said this before right that manatees are mostly related to elephants then dolphins and whales

  19. They look like a giant cuttlefish and that's a compliment to the species of the manatee just letting you know

  20. Alien abduction story…..I honestly laughed out loud with that one. Glad these majestic sweet creatures are recovering in quantities.

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