My guess and it IS just a guess is that he went head first into something delicious and his head and forelimbs became stained... Might have been a chemical reaction from acidic juice, etc.
From personal experience, the more UV they get, the darker the skin and such get. Just like if a person routinely suntans.
If you look where the color is, it's on the top of legs and head, not uniformly throughout the skin. I am almost certain it's from basking under a much too strong or close UVB bulb.
One of my Sulcata's loves to bask. It will sit under the heat emitter/UVB for most of the day. He is far darker than the other guy, who avoids the heat like a plague.
His "sun tan" is the exact same pattern as the one in the picture above, but not to the same extent.
As I said, I am nearly positive that it's from too strong of a UVB bulb or is much too close.
Those recommendations on the back of the packaging for distances are not because the company is being helpful, but in actuality anything closer than what is shown can cause damage and potential liability for the company, if not stated.
If the substrate is reptibark and it gets wet I could see it staining the tort. I know when it gets in my water dish everything is stained the same color as that tortoise.
If the substrate is reptibark and it gets wet I could see it staining the tort. I know when it gets in my water dish everything is stained the same color as that tortoise.
i have seen torts get stained from substrate. always comes off when they shed though. (remember the ivory sulcata thread by DeanS. the stain is so vivid on the pale skinned sulcatas, then it's back to white on the updated photos).
i agree that first photo looks like it's too dry to cause stains, but we do not not if the substrate in the before picture is still the one being currently used....what if the owner switched to damp coc coir? so substrate is still a posibility...or the darkening can also be due to UV exposure.
regardless of the reason for the stain, my best guess would be since this sulcata does not appear to be growing, it may not be shedding, hence the accumulated dark pigment? i have seen it on geckos, they become very dark when they miss a shed or two but get back to their bright colors after a successful shed. i am no sure if it's the same way with torts, since they shed skin in a different way.