I have two chicken coops as rabbit hutches. My fawn lion-head lop beds down at night with hay & his heat pad & likes the shelter. My dwarf neitherland stays in the run ... I have put a cat basket with cushions & blankets down, fleecey blankets a grass nest & covered the run in heavy duty packing bubble wrap. The hutch area has a cat rustle sack piles of hay & a heat pad & he wont get in it. What do I do I dont want to get up to a frozen rabbit they are both about 8 months old both buck rabbits.
I am sure your rabbit would go inside if he was cold as it would be a natural instinct. It sounds like he is much more comfortable in his run. I would not worry as he is choosing to stay there.
they are nocturnal-up at night
