“Hi there, I have two neutered bonded bunnies and last night I caught the male running back and forth around the cage wildly. It is not a small cage – 5 foot by 3 foot by 3 foot. Ultimately, I was wondering could this mean that he is happy or scared?”
Short answer: This bunny not happy, necessarily. He may also be a mixture of excited, playful, and energetic…
That being said, this type of behavior could indicate a fear response. Watch his movements: Is he running frantically? Is he running to the same spot, hiding, digging, making sudden jerks, or alarming sounds such as squeaks or growls? (Yes, bunnies can growl!) Does he seem frantic? How about his poop? (Lots?) These all indicate stress and anxiety in rabbits.
What about his behavior? Does he seem unfriendly or nervous if you approach? If so…is there a sound playing in the background when this happens? Anything from a tone in a song, to a movie, to some minor tone or note we may find normal, some rodents can find jarring (e.g. high pitched humming, drilling, thudding, vibrations, or outdoor sounds like car beeps/parking, etc…)
If it’s a young bunny who is running in a playful-seeming manner, like hopping and darting and generally looking silly, it sounds like he’s just excited, and getting his daily exercise.
I commend you for being understanding enough a pet owner to give your bunny a larger cage! Still, you still have to keep in mind that the majority of these creatures lives in the wild–which means their lives entail running, bounding, leaping, and scurrying from place to place, and often very far distances.
Without this, they cannot help but be stressed at times, and they display this stress through frantic, nervous behavior.
That’s not to say you’re not or cannot provide simulated physical stimulation for him. His living situation sounds fine. But when he’s feeling the need to get that natural burst of energy out of his system-try to provide him with a larger play space. This doesn’t have to be anything fancy. Just somewhere safe he can bound and bounce around in…and cant escape from! (Like a living room with an area blocked off for him to run within).
Again, bunnies are built to run: from danger, for play, for show, for socialization, for survival.
In other words, he sounds fine, albeit stressed or perhaps pent up. Make sure he isn’t always acting this way, and isn’t displaying signs of nervous agitation (google signs of nervous rabbit behavior for more information). Simply giving him more space and a change in activity when he acts this way should help.