BLUE TONGUE SKINKS

My two youngest BTS, for the past week or two, have seemed to be a bit itchy. I catch them lightly nipping at their own lower bodies, and sometimes seem to tilt themselves to rub their lower sides against their substrate. I've inspected them carefully, and I couldn't see any mites or other indications that it might be bugs. My next guess would be maybe their substrate is the problem, but my two young-adults are on the same sub and seem to have no itchy problems.

Any ideas?

Mine do that when preparing to shed, that's about all I can think of.

Maybe getting ready to shed and/or maybe humidity too low. Keep an eye on them for sure.

Turns out it IS mites. :C I checked the skinks over again today, and noticed one or two tiny crawling dark dots. UGH. x_x I've been spot-cleaning the cage once a week, but I guess I'll need to make it every day or every other day. That, or their substrate is hanging on to their pee. I'm not sure. I just ordered some new substrate, and I'll be grabbing some anti-mite spray, and cleaning the cages out thoroughly.

Only other cause I can think of is that I purchased an enclosure from craigslist a while back, that came with several hides and a large piece of driftwood-type thing. Stupidly, I didn't put them through the washer before using them. x.x So, if the mites didn't come from me not cleaning more than once a week, they could've come from those hides/enclosure already being contaminated.

Whatever caused it, I'm taking measures to fix the problem and make sure it can't happen again. My poor babes! ;n;