He should be fully grown at this point. What do you use for UVB? Is it a newish light. I'm trying to think of what could be causing him not to eat. Some dragons are just lean, I have 2 that I have trouble keeping weight on, so I've given them babyfood to get them through periods where they just don't want to eat. And as for stressing out when you take him out, I'm not sure about that either. Do you handle him alot? Dragons can get really picky, especially this time of year, they go through "spring fever" when they only think of breeding, not eating. Even if you have a single beardie it can affect them, too. What is he eating at this point? Anyway, start by measuring his length & his weight. And measure him from his snout to his vent. Beardies tails can be different lengths, so I measure all of mine that way. For an example: Didi is 7 1/2" from snout to vent, he's 6 yrs old & weighs 418g. Leo is the same length from snout to vent but he's 492g and 5 yrs old. Rubio is 10 1/2" from snout to vent, he weighs 749g (yes he's a big boy!) and is 4 yrs old. Lonzo is 9 yrs old, is 8 1/2" from snout to vent & 508g. Gabriel, my newest rescue, is 7" from snout to vent & 282g; he's 2 yrs old & is really underweight & undersized. So that gives you an example of different beardies. They're all under power suns & they all have new lights. I didn't realize their lights had gone past their due dates & they didn't have UVB for a month, so that also affected their appetites. Now that the lights are new, they're back eating & gaining weight again.
Deb