LOL I’m sorry, but that’s new to me.
When I trained Sammy to go back in her house with a treat in the morning (before I left for work) and at bedtime, she would jump in and out of her xpen about 3 times in anticipation before landing Inside the cage to get the treat. She now doesn’t need it, but she expects 2 treats daily, so stays put and chews on the bars instead. My mother took over treat duty.
None of which helps you.
First idea: shake the treat tub INSIDE his habitat so he runs there to hear it, maybe. If the tub is big, get a smaller plastic jar to put treats in to shake instead that’s easier to carry. Then set the treat down below it. See if he comes closer.
2. Will he let you pick him up? If you can lift him just slightly off the floor enough to set him down in front of his treat inside his cage, it might work. Do not pick him all the way up to carry him. That may backfire badly, and is unnecessarily risky. Plus he may associate it (if he doesn’t like it) with going back, making it even harder to get him in.
A variation on this would be, if he’s frozen still, gently push down on his shoulders, which bunnies take to be a dominance move from an alpha animal, slide your other hand under his belly, and keeping low, move him into the habitat next to the treat, serving him up on the floor there like a spatula. Still not the best idea.
3. Hold the treat inside the cage, be ready to touch it to his lips, but push his little behind gently toward it to get him to move.
4. Use a lot of patience, wait for him, hold it in the habitat, touch his lips to it, and once he’s moved in himself, praise him enthusiastically and give him a second one. Like, first a treat then a bonus raisin. So he learns that if he goes in himself, there’s even more of a reward.
And just take a look around and listen in case he’s aware of something you’re not, like someone else might hear the treat jar too and be coming in for it. Or the TV is on making noise that’s scary. Or someone moves around when you do it and he doesn’t know if it’s safe. He may be freezing before exposing himself to unsafe conditions when he goes for it. Bunnies are weird. You don’t know what they’re thinking.
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