Humidity, BookLungs,Waterproof, ICU, Swimming - How Does This Work?

Okay, I get that Ts have a waxy outer coating, exterior non-penetrable -- even human skin has similar properties, human skin can absorb to some degree but you don't take a bath and get out weighing 30 pounds more because you absorbed water -- so it limited. (I am going somewhere with this, honest).
But if Ts cannot absorb water -- then how does humidity (whether in their enclosure or in ICU) assist a dehydrated T or a moulting T?

I DO understand drinking water helps. I tell my home health clients to drink water not just to avoid dehydration but for dry skin too -- moisturizer may help "lock in" moisture (like a Ts waxy coating) but it's what goes in that helps, not what's in the environment alone. Ts obviously may differ, hence my asking.

Then I see these freakin amazing swimming/underwater vids of Ts/other spiders and am amazed.
But could someone explain how their book lungs don't saturate and cause them to develop T pneumonia?
Obviously, their lungs differ from ours and of that of fish, but HOW?
So:
1) how does environmental humidity assist a T with a non-penetrable waxy coating?
2) how do their book lungs function with environmental water or humidity?
3) Why is not drinking water (or eating hydrated feeders) alone not sufficient?

This is a "I wanna understand better" question, not an attack on the fact that we all use these methods (adding humidity) with our Ts.
Thanks in advance.

what an interesting post, lol, too bad this is over my head. I look forward to reading responses.

Hmm, great question. I never asked why, I just took on the advise but am very interested to see what the responses will be.

hahaha, I know, right? I think we'll be learning something new.

Here goes with an idea regarding humidity/hydration. I have never seen one of my Ts drink from a water dish. I assume that they just do it when I'm not looking. They aren't monitored with a camera 24 hours a day, so obviously they do things I don't see. I have observed with my Ts that when I wet a spot of the web or sub, they go to it and appear to be sipping water from the damp spot. I don't know that this is true. In nature it's not as though every T lives within a few feet of a puddle or body of water, so I would think that the most consistent source of hydration for them would be rain falling on the ground. Possibly they can sip droplets much to small for us to discern off of the ground.

As far as humidity goes, most folks that have lived in a dry climate and moved to a humid one, or vice versa, have likely observed the differences in their hair and skin between the two climates. My observation is that in more humid places, my skin and hair are more moisturized and feel better. Here in my lovely dry area, my skin dries out so badly that it will split open, as though the world around me is leeching the moisture from me. Running a humidifier in my room helps to avoid the dried out skin issue to a degree, as does drinking a ton of water. Is it possible that a Ts exoskeleton suffers the same dry out that my skin does in a drier climate?

As to the swimming, that one beats me. I was wondering the same thing. If you don't want to get water directly on a book lung when dampening a stuck molt, how on earth do they swim?

Sana said:

Here goes with an idea regarding humidity/hydration. I have never seen one of my Ts drink from a water dish. I assume that they just do it when I'm not looking. They aren't monitored with a camera 24 hours a day, so obviously they do things I don't see. I have observed with my Ts that when I wet a spot of the web or sub, they go to it and appear to be sipping water from the damp spot. I don't know that this is true. In nature it's not as though every T lives within a few feet of a puddle or body of water, so I would think that the most consistent source of hydration for them would be rain falling on the ground. Possibly they can sip droplets much to small for us to discern off of the ground.

As far as humidity goes, most folks that have lived in a dry climate and moved to a humid one, or vice versa, have likely observed the differences in their hair and skin between the two climates. My observation is that in more humid places, my skin and hair are more moisturized and feel better. Here in my lovely dry area, my skin dries out so badly that it will split open, as though the world around me is leeching the moisture from me. Running a humidifier in my room helps to avoid the dried out skin issue to a degree, as does drinking a ton of water. Is it possible that a Ts exoskeleton suffers the same dry out that my skin does in a drier climate?

As to the swimming, that one beats me. I was wondering the same thing. If you don't want to get water directly on a book lung when dampening a stuck molt, how on earth do they swim?

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Tarantulas acquire humidity from moisture in substrate, water( I have seen my T's drink from their water dishes), humidity in air, and their prey. So yes Sana to answer your question, T's exoskeletons are affected from wetter to dryer climates.The breaking point is up to interpretation. T's that are said to live in 50% humidity have thrived in conditions dryer than that by at least 10%..Sometimes more. Once a sling has developed into a juvenile, their exoskeletons can retain humidity. I've seen my T's hold on to their exoskeleton for extra moisture in post molt. On the opposite side of the spectrum, T's have been known to grow mold on their exoskeletons due to to much humidity, I'm sure combined with lack of proficient ventilation, depending on the speices.

I've been googling, things like if Ts can "drink" moisture from the air (no definitive answer but appears unlikely); if moisture could be absorbed through book lungs (more likely book lungs close when faced with water/swimming since they are meant for air exchange). I googled how ICU really works (no one seems to know but there are lots of guesses -- some insist that body must be in contact the moist paper towel - but how the moisture is absorbed isn't clear --Ts drink it from paper towel? For Ts to absorb moisture through their surface area or book lungs seems less likely.
And I know the value of ICU is debated anyway. I sometimes think of ICU like an end-stage cancer tx -- it just gives people something to try when they don't know what else to do. I realize many here have tried ICU and their T pulled through but whether that was because of or in spite of the ICU I can't find conclusive information. The ICU information appears to be all just observation and personal experience (please don't flame me -- I am not discounting this) but I was looking more for lab research stating what actually occurs/the mechanism of ICU success. And I don't have access to such journals that might explain it.
I know I took Zoology in college (over 25 years ago), but I don't really recall Ts or insects being covered in the course. I remember Micro and AP better.
I am thinking of just buying an old college textbook for more research (wish I could find my old one). I have never dejunked a book I didn't later regret.

I personally have never seen a good reason for an ICU. For example, some ones tarantula is not moving and is starting to curl "ICU!!!". It works. But it was because the tarantula was dehydrated. Putting the tarantulas mouth would do the exact same thing but not stress it out as much. Seems kind of pointless to me.

Biollantefan54 said:

I personally have never seen a good reason for an ICU. For example, some ones tarantula is not moving and is starting to curl "ICU!!!". It works. But it was because the tarantula was dehydrated. Putting the tarantulas mouth would do the exact same thing but not stress it out as much. Seems kind of pointless to me.

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I was running on the thinking that rather than moving a T to an ICU, why not move the ICU into the habitat? If the problem is dehydration, as you said, give water on or near the mouth, or increase humidity in the habitat with a damp paper towel or moss. Seems like that would in fact be the better way to go, as it would be less stressful for the T. On the other hand, if dehydration isn't the problem, or the issue hasn't been determined, is it better to remove them from the environment that could possibly contain a pest or other problem that is the cause?

How would an ICU help against a pest? The ICU will just offer unnecessary humidity, once again, a water bowl will do exactly what an ICU will, just an easier way. And putting an ICU in the habitat would mean you aren't moving a potentially immovable tarantula, how would it get there on it's own? You would have to put it there. What problems can you think of where an ICU would help? Just my 2 cents lol.

Ellenantula said:

But could someone explain how their book lungs don't saturate and cause them to develop T pneumonia?

So:
1) how does environmental humidity assist a T with a non-penetrable waxy coating?
2) how do their book lungs function with environmental water or humidity?
3) Why is not drinking water (or eating hydrated feeders) alone not sufficient?

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I will have to come back and provide references for my answers, but I wanted to at least get this out here now in order to get those wheels of thought going.

There is one aspect of a tarantula's morphology that is being overlooked when considering how a tarantula's lungs do not flood with water when submerged. The entire body, including the book lung coverings, are covered with dense bristles that not only repel water but trap air. This makes the spider buoyant and will float in water. Those that can move under water can do so by propelling themselves underneath the surface and stay there by simply holding on to something using their claws and maybe the scopula pads on the tarsus and/ or metatarsus. Tarantulas, and all spiders, require such a low amount of oxygen to survive that they can stay submerged in water for a lengthy amount of time using just the oxygen trapped around the book lungs.

To answer your questions by number...

1) Some say that different species will have a different thickness of the waxy layer and exocuticle therefore some lose more water than others and require more relative humidity to stay hydrated. Don't forget, the exocuticle and waxy layer not only keeps water out, but keeps in the spider's body as well. It is thought that tarantulas from a more arid habitat developed a thicker exocuticle and waxy layer to hold fluid in the body than the those from tropical habitats that don't need it. This is also the same principle when keeping spiderlings at a higher humidity than adults in that spiderlings have not yet developed a thick enough exocuticle and waxy layer to keep moisture in the body. I'm not aware of any formal studies to show a difference between tropical and arid species so consider this speculative. For arid species, environmental humidity would not help in hydration but in a tropical species it might. Key word, is "might."


2) I'm not completely sure what is being asked with "how do their book lungs function with environmental water or humidity" in that they function in the same way with little humidity or none.

3) See number 1. Drinking water and eating hydrated prey is the primary source of moisture for all tarantulas (and all spiders).

As for the ICU. Sometimes it works sometimes it doesn't. It has been said by Stan Schultz (who I think popularized if not invented the ICU as we know it) that it is not understood how it works but it does. The theory is that the tarantula's body will wick water from a moist paper towel in the ICU to the mouth providing it with drinking water. I will have to go find that information again and provide a link.

See http://people.ucalgary.ca/~schultz/icu10.html

All in all, the amount of moisture in the air really wouldn't help a tarantula with any of it's physical ailments but the overall hydration and nutrition will prevent most problems like molting. I believe it just makes people feel good that they are doing something to help their ailing pets, but really, no one knows for sure if it works or really even how it does.

AphonopelmaTX said:

....wick water from a moist paper towel in the ICU to the mouth providing it with drinking water.

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Excellent! I didn't wanna waste bandwidth quoting all you wrote but I enjoyed the read immensely. Compared to my "google" research, this sounded far more academic.
Drinking does seem to be the primary way of hydration, whether from water dish, misted web/enclosure sides, damp substrate, wet paper towel, etc.
I suppose slings do have a varying amount of waxy water-resistance and so might benefit from a more humid environment.
I find this so interesting -- and as I was researching (if you can call anything on google research) I got into the book lungs study and then into fish gills; but it seems Ts only used book lungs for air exchange and would indeed "hold their breath" or use "trapped air to breathe" so to speak under water. A few ICU advocates certainly imply the moisture is absorbed through T exterior or book lungs -- the drinking makes most sense to me.
It seems established by many on these boards that ICU works if the problem is a hydration issue (logical to me) but it's not a one-size-fits-all cure.all.
If you post more on this, I think you will find a lot of interested readers.
Thank you so much for responding.
And I think I will chase down a textbook for further reference, at least an arachnid-style anatomy and physiology book (and I don't mean simple diagrams of body parts -- those are everywhere!)
Thanks again!

Ellenantula said:

but it seems Ts only used book lungs for air exchange and would indeed "hold their breath" or use "trapped air to breathe" so to speak under water.

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No spider would actually hold it's breath under water since their respiratory system is passive. Meaning gas exchange happens without muscle contraction to inflate the lungs.

For more information, see "Respiration in Spiders" at http://atshq.org/downloads/
The best textbook style book on spider biology is "Biology of Spiders" by Rainer Foelix

It also helps when doing research on tarantulas that you consider texts concerning all spiders and other mygalomorph spiders specifically. You will also find relevant information if you study invertebrate biology in general. One of the points I always advocate when someone has questions on how their spiders work is to study the biology of all arthropods first to get that base understanding and drill down to specific invertebrates. That way you can make better informed assumptions and ask more specific questions when it comes to tarantulas or spiders.

Thank you, I will look into that textbook.
"Hold their breath" was my original research (indicating closing off their book lungs under water) but yours made more sense that they use "trapped air to breathe."
Thank you again!