If I take her outside to sun, and patiently drip water from my spray gun on her nose, Skeeta WILL drink for me. Other than that I haven't really seen her drink (or eat for that matter) in nearly 3 years.
Pendergast, on the other-hand, eats from tweezers easily.
As long as they are healthy, you don't have to SEE them eat or drink.
An old myth says chameleons eat air and don't need to drink (don't try it out though)
"In the 3rd century an encyclopedist and collector of odd data, Solinus, whose work happend to have been translated into English in 1587 wrote:
"Throughout all Asia is great store of Chameleons, a fourefooted beast, in making like a Lucert, but that hee hath straight and somewhat longer legges growing to hys belly, with a long tayle wrythed rounde in, with hooked talants finely bowing inwarde, slowe of gate, and in a manner trayling like a Snayle: rough bodyed, wyth such a hyde as we see Crocodiles have, and hollowe eyes suncke farre into his head, which he never shadoweth with twinckling. Moreover, he beholdeth thinges not with rolling the bals of his eies, but with staring continually forward. His mouth is ever gaping, and serveth to do no kind of thing wyth all: for he neyther eateth meate, nor is nourished with drink but liveth onely by drawing in the ayre, which is hys onely sustenaucne. Hys colour is variable, and everie moment changable: so that to what thing he ever beleaneth himsefe, hee becommeth of the same colour."