# Swimming and floating tortoises



## AldabraNerd

Hi All,

There are some questions and thoughts scattered through this thread  about tortoises and swimming/floating. I thought I'd add a bit of info here in one place, where it can expanded on by others.

So yes, many tortoises float very well. That's how they ended up on isolated oceanic islands pretty much around the world. The two largest surviving tortoise species, Galapagos & Aldabra giants, float exceptionally well and can survive for a long time in sea water.

One amazing case was reported in a paper by Gerlach & coauthors, in 2006.
The abstract reads: 






The single most amazing part of this paper is the photo of the tortoise, covered in barnacles on the lower half:





The size of the barnacles indicates that this tortoise had been drifting for a minimum of 6-7 weeks! 

According to prevailing ocean currents, the Aldabra Atoll is indeed the likely point of origin of this tortoise. I'll post a bit more on Aldabrans there, and their relationship with water, soon - just got to dig out them photos first 

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Edit: The Gerlach 2006 paper is attached to this post.


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## luvpetz27

Amazing!!!!!!!!!
Thanx for sharing!!!


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## Yellow Turtle

Nice post. Thanks.


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## AZtortMom

I knew it


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## CtTortoiseMom

Wow, that is amazing. Thanks for sharing!


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## sibi

Well, that settles that...tortoises swim.


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## Tony the tank

Great info..

Thank you or taking the time to post this..


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## mctlong

Wow, that awesome! 

Thank you for sharing!


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## Yvonne G

I can't stand it!!! I want to grab the tweezers and pick all those barnacles off.


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## tortadise

emysemys said:


> I can't stand it!!! I want to grab the tweezers and pick all those barnacles off.



Haha I know yvonne. My ocd is kicking in...must.........remove. Fascinating story though.


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## Tom

Wow. Never seen that before. I've heard of a few hours or days in the water to get from one island to another, but wow, that's pretty incredible.


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## Shannon and Jason

That's fascinating information I hope to hear more on this. Thanks!


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## Baoh

Awesome photo and information.


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## cemmons12

Wow, 6-7 weeks? Thats amazing!


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## leonardo the tmnt

That's amazing!!!


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## biochemnerd808

Wow. Tortoises just amaze me more and more every day. No wonder they have been around since the times of dinosaurs.


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## Chinque

Woah! That is SO cool! Thanks for sharing, I never knew that!


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## wellington

That is really amazing. I would have thought he would get totally dehydrated, the salt water and all. So, my question is, can they or have they adapted to be able to drink salt water and large amounts don't effect them? Do you think that he did t drink any but only absorb it and that doesn't effect them. Possibly, they can absorb salt water? That's a long time floating at sea. Thanks for sharing so, interesting.


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## sibi

Man, I've got my own theory on how this tort got those barnacles. During his swim, there was a rock protruding out on the middle of the ocean and he took a long long break before starting out again. Or else, he met a whale out there and bumped a ride. The whale and the tort shared the barnacles. How about that for a story? Isn't that incredible?


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## AldabraNerd

wellington said:


> That is really amazing. I would have thought he would get totally dehydrated, the salt water and all. So, my question is, can they or have they adapted to be able to drink salt water and large amounts don't effect them? Do you think that he did t drink any but only absorb it and that doesn't effect them. Possibly, they can absorb salt water? That's a long time floating at sea. Thanks for sharing so, interesting.



I don't think/know of that tortoises can drink salt water. I'd think not, but simply that it lived off its internal reserves (which they can do for months). Probably it even used/lost less water by floating in the sea, than it would have in the dry & hot environs on Aldabra?




sibi said:


> Man, I've got my own theory on how this tort got those barnacles. During his swim, there was a rock protruding out on the middle of the ocean and he took a long long break before starting out again. Or else, he met a whale out there and bumped a ride. The whale and the tort shared the barnacles. How about that for a story? Isn't that incredible?



Yes, and out there, somewhere, is now a hybrid tortoise-whale creature swimming around, wondering where & who his parents are!


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## skottip

Lets not forget, it was swimming/floating in"salt water". I am willing to bet if that tortoise entered a body of fresh water, we wouldn't be having this conversation.


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## EricIvins

Its actually quite simple as to how this animal survived - The floating part is fairly self explanitory......I doubt the animal swam too much......

However, when it rains there is a layer of fresh water that is created on top of the sea water and lasts for some time depending on ambient conditions. This temporary halocline is also how Sea Snakes survive, and I'm sure many other Island hopping species that cross salt water......


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## pdrobber

emysemys said:


> I can't stand it!!! I want to grab the tweezers and pick all those barnacles off.



me too! can't stand stuff like that! like the Pipa pipa Surinam toad with the eggs in its back...ahhh! want to pick them all out!


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## Zamric

wellington said:


> That is really amazing. I would have thought he would get totally dehydrated, the salt water and all. So, my question is, can they or have they adapted to be able to drink salt water and large amounts don't effect them? Do you think that he did t drink any but only absorb it and that doesn't effect them. Possibly, they can absorb salt water? That's a long time floating at sea. Thanks for sharing so, interesting.



If I were to venture a guess on this I would GUESS that if a tortoise can absorb water thru it's skin like osmosis.... wouldn't the skin act as a filter to keep the salt out and still stay completly hydrated? Food however would still be an issue.




skottip said:


> Lets not forget, it was swimming/floating in"salt water". I am willing to bet if that tortoise entered a body of fresh water, we wouldn't be having this conversation.



The results would be the same. Tortoise have thier lungs at the top of their caripace....natural floatation device.... they sufficate when left on their backs because of the preasure of the organs on the lungs.


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## argus333

wish that would float by my house!!!


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## TortyTom

WOW!! That is amazing and fascinating at the the same time!


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## kanalomele

Love it! Thank you for sharing. Im continually taught how much more I have to learn.


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## AZtortMom

Amazing


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## Livingstone

Zamric said:


> wellington said:
> 
> 
> 
> That is really amazing. I would have thought he would get totally dehydrated, the salt water and all. So, my question is, can they or have they adapted to be able to drink salt water and large amounts don't effect them? Do you think that he did t drink any but only absorb it and that doesn't effect them. Possibly, they can absorb salt water? That's a long time floating at sea. Thanks for sharing so, interesting.
> 
> 
> 
> 
> If I were to venture a guess on this I would GUESS that if a tortoise can absorb water thru it's skin like osmosis.... wouldn't the skin act as a filter to keep the salt out and still stay completly hydrated? Food however would still be an issue.
Click to expand...


Tortoises cannot absord water through their skin, the only place that water absorbtion occurs externally would be the cloaca. That animals volume is so great that it was able to survive based on its reserves.
It's because its skin is not permeable that it was able to avoid dehydration. Tortoises cannot drink salt water.


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## Zamric

Livingstone said:


> Tortoises cannot absord water through their skin, the only place that water absorbtion occurs externally would be the cloaca. That animals volume is so great that it was able to survive based on its reserves.
> It's because its skin is not permeable that it was able to avoid dehydration. Tortoises cannot drink salt water.



Tortoises don't absorb water thru their skin? Then why do we soak them to help re-hydrate them? Sure, they may drink some water while they are soaking but not always, and not always enough to totally re-hydrate.


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## theelectraco

I am really curious to know the answer of whether they absorb water through their skin or only through their cloaca. If it is only the cloaca then I'm assuming it is very absorbent


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## cruiser12

Woah, a month and a half of floating in the sea. Im kinda surprised he wasn't eaten by a shark or something! He also looks a little fat for not eating much for 6-7 weeks...


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## TortoiseBoy1999

emysemys said:


> I can't stand it!!! I want to grab the tweezers and pick all those barnacles off.



I know right!


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## james1974

I never would have thought that wow we learn something new about tortoises everyday.


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## ALDABRAMAN

*So interesting, great post!*


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## Ansh

So my question is, do all tortoises swim instinctively or is this something that is specific to those species that have found their way on to oceanic islands. Unlike the aldabras, some inland species have not really had access to large bodies of water for thousands of years. Does anyone have experience with CB tortoises swimming?

Really interesting post!!


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