We were "foster parents" for a co-workers RES for a 4 months. My RES and the new one didn't show any major aggressive behavior so it was fine. They didn't really seem to interact that much and often pushed each other around to get at the food or basking stops. In fact, the new one (3"
would lay on top of my smaller RES (2.25"
and annoy it.
Anyways, two days ago, we gave back the turtle to the original owner who can take care of it now (was moving around and stuff). After a day, my RES seems more frightened and listless. Before, he used to swim around actively, come to me to beg for food, etc. Now he hangs out in the far corner of his tank, doesn't eat much and swims away from me.
I am worried now. 
1) is it loneliness? I thought RES weren't really social creatures like dogs
2) is he sick?
3) is it just moodiness?



