Hi Ash!
Your comment (Everything I have read says monitors don't drink unless dehydrated). can be interpreted different ways. Without diggin up official reports or book excerpts, I'll try to explain my take on it.
I suppose it comes down to the level of dehydration. I believe a monitor drinks in order to avoid dehydration or becoming more dehydrated.
"Dehydration" is the loss of moisture/water. Sometimes we think of it in severe terms instead of the natural minor process that it can be. What I'm trying to say is, don't automatically assume the worst if your sav drinks water.
When I mist a cage I mist all parts, even burrows, hides, etc... If you keep a clean bowl of water available, and it gets too dhydrated, it'll drink from that water bowl, whether it has defecated in it or not.
The fcoming out during misting now can be a few things; Firts & foremost, it could mean that it's not staying hydrated enough. It could also be a natural thing, something they do in the wild.
So the first thin you do is look at your humidity in the cage and you said it was 80%, which is good, maybe a tad on the high side but as long as your careful about keeping an eye out for fungus n such, should be OK. But with that high of humidity good ventilation is needed.
Two things you didn't mention that I feel could be key in figuring out what's going on. Substrate and type of cage top.
If you're not using a substrate that can hold humidity fairly well and you have a screened top, where are you taking your hudidity level readings from, what height within the cage?
Under those conditions the humidity can quickly escape, rising above the the monitor ohysical height, and on out the top before the monitor has a chance to absorb any of it.
One last thing, I feel that your basking spot temperature should be at least 135 degrees (F), or a tad higher. Set it to that temp, observe the monitor's basking behavior over the next feew weeks or so and incease/decrease accordingly (just a few degrees at a time) Again, give it at least a week before adjust ing again.
Sorry this turned out to be so long, I have always had problems with taking 30 minutes to tell a 5 minute story. I try to get too specific, too many details.
Best wishe!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American