Depression within leopard geckos?

you don't give any info what are they acting resembling ?
Do they still eat?
if they are just hiding adjectives the time don't worry they always do that
If you could have given us more fact we could help you out more. If he is listless and not eating then it could be a few things. I don't know if leos go into brumation (hibernation), but it could be a cause. If it's not that your little one could have parasites or worms. A trip to the vet might be surrounded by order.

Answers:    "stressed" is the word you're probably looking for. If a cagemate has passed away, the change within the environment could cause stress. The gecko would therefore need time to be accustomed to the emptier compound and newer surroundings.

If your gecko is refusing to eat and is listless, check for the last time it pooped, offer different delicious food items (waxworms, silkworms), and arrange a vet stop by. Leopard geckos do brumate to a degree; they are generally cooled before breeding this time of year. However, they never stop consumption completely, and will still move around. They eat less and move less, but never completely stop any.
Leos don't get "depressed". That's just us anthropomorphizing them. They feel stressed due to not fitting temps, illness, living with another leo, etc. Otherwise, leos shouldn't be stressed.
Your half right dear, leopard geckos get stressed out glibly and because of that some will refuse to eat, not move..etc... so i see how u think its depressed.. do you enjoy a uth? whats his subtrate? there are many reasons why he can bring stressed.
Give it Prozac.
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