I can only assume that what photographer Porsupah Ree captured here are binkying bunnies. A binky is a playful and happy expression made by a rabbit in which it jumps in the air and twists its body around in a convulsive fashion.
Actually, it looks like they’re trying to establish territory. Rabbits are fiercely territorial, and on the campus where I used to take classes, there was a lot of them.
They’d charge at each other, jump 3 or more feet into the air whilst spinning around, run away, and repeat. This could go on for minutes at a time.