Hello, My large male tortoise lives outside in his large insulated house with a heat lamp. Normally he is very active and walking around most of the day, grazing on the grass, being social with the tortoise next door, and eating the veges I give him. For the last several days he has wanted to stay in his house and not venture out. His eyes and nose are clear and he seems alert and active otherwise. I did give him a warm soak in the kiddie pool the other day but nothing has changed. It was colder last week so I am wondering if that is the issue? He weighs about 140 pounds and I am unsure of his age as he was a rescue. Any ideas or thoughts? The other tortoises are out in their own enclosure and are very active. " Speedy" has the run of the back yard and can go almost anywhere he wants but usually is basking in the sun or grazing. Thanks for any help. His house is always warm and his heating lamp comes on at dusk and the temperature inside is between 65-70 degrees.