Why is bunny poop smelly?

Answer 1

Rabbit feces isn't smelly: it comes out in dry, hard balls, and unless you put your nose right up against it, you won't smell anything.

Rabbits have two kinds of droppings: feces, and cecotropes. Cecotropes are smaller than feces and they're mushy. Sometimes they're found in singles, and sometimes they're stuck together in a grape formation. Normally, rabbits eat their cecotropes directly from the anus and you never see them. (This is a form of re-ingestion, like cows chewing the cud.) Every once in awhile you might find a spare cecotrope. However, if you're finding cecotropes every day, and/or they're stuck in your rabbit's fur, and/or if they're as big as regular feces, that's a sign that something is wrong. Your rabbit may be sick, or you may be feeding him the wrong diet, so you should bring him to a vet with experience and knowledge in treating rabbits.

Rabbit urine can be very smelly, especially if the rabbit isn't spayed/neutered (because the sex hormones come out in the urine), and especially if it sits around for awhile (because it will build ammonia). A rabbit's litter should be cleaned out every day or two. If urine is left to sit, it develops ammonia which isn't healthy for anyone, rabbits or humans: it can damage the nasal passages.