To check for fleas- comb the bunny with a fine toothed comb (they even make combs called flea combs) and look thru the bunnies fur for any fleas or flecks or debris. Put any specks or debris that you find on a white piece of paper and put a drop of water on the specks. Mix the water into the specks and see if they remain solid or if they turn reddish in color. If they turn reddish in color- that indicates the presence of fleas- as what you are finding is “flea dirt” (flea poop) and since fleas eat blood- their droppings will turn reddish color when wet.
Fleas usually do not like light and will run way when you are parting the fur. They seem to like to hang out around the back end/ rump of animals and on their bellies.
Sometimes it can be difficult to find live fleas on rabbits and cats- as they groom themselves frequently and often ingest adult fleas when they grooming an area- that is their way of ridding themselves of the pest that is biting them.
If you suspect yoru rabbit has fleas- be very careful what you use to treat them and other pets in your household. Some flea treatments can be fatal for bunnies. Even treating another animal that you bunny plays with can be harnful if your bunny comes into contact with the flea treatment.
Julie