It's a funny thing. I don't really shoot bunnies, so for two years I notice them every now and then. They are a hair (no pun intended) more timid than up-state bunnies.
Finally I notice; "man these are big bunnies!"
I noticed this when my dog chased one. (Bad Chato, bad Chato, no buiscuit) and would have caught it if I hadn't of stopped him, because the bunny had a hard time in the brush. I suddenly realised that a normal bunny would have used the brush to escape the "predator," while this one was to big.
Some kid doing his thesis should look into this.