Thanks for the reply.

I took him in last night. I checked him again when I got home this afternoon, and he is much improved! So I haven't called the vet. I guess outside hibernation is not in the cards for him this year!
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0.1.0 ornate box turtle
1.0.0 eastern box turtles
1.0.0 Yellow belly slider
0.1.0 Red belly cooter
0.1.0 Australian shepard
1.8.0 chickens
1.0.0 Dutch rabbit