Understanding Behavior
Rabbit Behavior
Sharon L. Crowell-Davis, DVM, PhD, DACVB
University of Georgia

October 2006 COMPENDIUM

Domestic rabbits are increasingly popular pets. A significant change in the past couple of decades is that rabbits are increasingly being kept as house pets rather than in outdoor hutches. Preventing and treating behavior problems in pet rabbits requires an understanding of the natural behavior of their wild ancestors and how it impacts a rabbit's behavior in the house. The domestic rabbit, Oryctolagus cuniculus, is descended from the European rabbit, which is a highly social species that digs large warrens. This can confuse veterinarians who are familiar with the North American Sylmlagus sp (i.e., cottontail), which is generally solitary and does not form large, organized social groups. The cottontail digs small hollows to rest in during the day but does not dig extensive warrens characteristic of the European rabbit. Further use of the term rabbit in this column refers to the European rabbit.

A behavior that has been critical to the transition of keeping rabbits as house pets is the ease with which they can be trained to use a litterbox. Litterbox training of rabbits is based on the fact that they surrpund their warrens with specific elimination areas called latrines or scrapes, which serve as signals to rabbits from other warrens that they are encroaching on another rabbit's territory. The domestic descendant of the wild European rabbit maintains the predilection for selecting and consistently using one or more elimination sites. The basic principle of litterbox training a rabbit is to identify where the rabbit is eliminating and place a litterbox there. Most rabbits continue to use the same site. There are multiple ways to begin litterbox training, depending on how the rabbit will be housed (see box below).

Litterbox Training
If the rabbit will be housed in a cage in the house part of the time and allowed to be loose in the house at other times (e.g., when someone is home to supervise the rabbit), it is generally best to train the rabbit to use a litterbox in its cage. To do this, confine the rabbit to its cage until it selects an elimination area (usually a corner). Place a litterbox at that location. Once the rabbit consistently uses the litterbox, prop open the cage door to allow the rabbit to roam. In general, rabbits return to the cage to eliminate.
If a cage will not be used because of owner choice or the rabbit has an aversion to it, owners should identify the area of the house in which they want the litterbox. Because a rabbit that has not been litterbox trained will choose its site based on parameters that are not fully understood, the owner cannot select the exact site, only the general area. (In contrast, the basic behavior used to litterbox train cats is their predilection for digging a hole in which to eliminate.) To select the litterbox area, confine the rabbit to the area (e.g., using a closed door, a baby gate, temporary indoor penning). Once the rabbit has seletted its elimination site, place a litterbox there.

Key Points
• The domestic rabbit is descended from the European rabbit, Qryctolagus cuniculm, which forms large, complex social groups and digs extensive warrens.
• Domestic rabbits have a strong drive to manipulate their environment; therefore, they should be provided with appropriate toys and opportunities to engage in species-specific behavior.
• Pet rabbits can be trained to use a litterbox because they naturally prefer to eliminate in specific, discrete sites. Because rabbits may eat litter, clumping and toxic litters must not be used.
• Because rabbits are territorial and establish dominance hierarchies, a new rabbit should be introduced gradually to prevent fighting.
• Rabbits that have frightening experiences with humans become afraid of them and may become fear aggressors. This problem is best prevented by using appropriate handling techniques and habituating rabbits to interaction with humans from a young age.

Rabbits may eat litter, which limits the types that are safe to use. Clumping litters should not be used because they clump in a rabbit's gastrointestinal tract. Pine and cedar shavings as well as litters with possibly toxic materials (e.g., deodorant crystals) should not be used. Safe substrates include hay, straw, aspen bark, nonclumping unscented clay, peat moss, compressed sawdust, and litter made from paper products, alfalfa, or oats.
As with cats, rabbits may exhibit individual preferences for certain substrates or combinations of substrates and for the size and shape (e.g., triangular or rectangular) of the litterbox. If a rabbit does not consistently use the litterbox, other substrates should be tried. Because rabbits may like to spend long periods sitting or lying in the litterbox, it is important that the litterbox be large enough for the rabbit to do so. If the rabbit frequently eliminates over the side of the litterbox, one with higher sides may be necessary.
Unlike cats, rabbits may move their litterbox. If it is important that the litterbox not be significantly moved, the owner may need to clamp or tie the litterbox in place. However, it is important to consider whether the exact position of the box is important in the household. If not, the rabbit should be allowed to move the box wherever it wants. This behavior may be derived from the fact that rabbits in the wild manipulate their environment not only by creating warren tunnels and rooms, called stops, but also by relocating their latrines. Once a rabbit has identified
the litterbox as its latrine, it may use the litterbox even if the owner moves it. Other rabbits remain "site loyal" and discontinue using the litterbox if it is moved.

Web site
House Rabbit Society
See www.rabbit.org/Hnks/mail-order-resources.html for
links to Internet retailers selling a wide selection of toys,
baskets, nontoxk cardboard "playhouses," and other
items for rabbits.
Bays TB: Rabbit behavior, in Bays TB, Lightfoot T, Mayer J (eds); Exotic Pet Behavior. St. Louis, Saunders Elsevier, 2006, pp 1-49.
Harriman M: House Rabbit Handbook: How to Live with an Urban Rabbit, ed 4. Alameda, CA, Drollery Press, 2005. (Recommended for rabbit owners; list price: $10.95)

Centuries of living in cages has not eliminated digging and chewing behaviors in domestic rabbits. Because rabbits may chew on cords and wires, indoor areas accessible to the rabbit must be rabbit-proofed, Cords, especially electrical ones, should be moved out of the rabbit's reach or covered (e.g., with PVC pipe). Valuable objects should be placed out of the rabbit's reach. Owners can prevent rabbits from digging in couch cushions and chewing book covers by providing objects that rabbits may dig into, chew, and manipulate. Examples include various nontoxic toys available for rabbits (see box on this page). Many toys designed for parrots also work well for rabbits. A basket with hay or straw provides an area in which a rabbit can dig and form a nest. Many rabbits use digging motions to rearrange towels placed in a box for them.

Introduction of a new rabbit to a household with a rab-bit(s) is a problem that many owners face. As with many species living in organized social groups, an established rabbit group generally does not welcome strangers. In addition, if an individual pet rabbit is obtained, especially as a juvenile, and is not exposed to other rabbits for months or years, it may have poor social skills. Therefore, a new rabbit should be gradually introduced to other rab-
bits to avoid injuries from fighting.

Although aggression toward other rabbits is motivated by a combination of territorial defense, dominance, and fear, rabbit aggression toward humans is primarily motivated by fear. It is important to remember that even when human interactions with rabbits are motivated by a desire to help and be kind, rabbits can become comfortable with humans only by learning that interactions with them are safe and do not lead to pain and distress. In preparation for being pets, rabbit kittens should be handled by humans. Rabbit kittens handled by humans or exposed to a non-predatory cat each day during the first week of life approach and do not show fear reactions to whichever species they were exposed to when tested after weaning.1
Subsequent experiences with humans can alter a rabbit's behavior toward them. If a rabbit is held in a painful fashion or dropped while being held, it is likely to become afraid of being picked up by humans. This fear response may be generalized to all humans, even if they do not attempt to pick up the rabbit. Fearful rabbits respond in a variety of ways: They may run away, crouch and freeze, or attack. If the attack results in the human moving away and leaving the rabbit alone, the rabbit will learn to repeat this behavior to frighten away humans. Although biting and scratching by these rabbits can be intense, the motivation is still fear. This makes the handling of rabbits by young children particularly problematic. Young children are likely to mishandle rabbits, often through naivete, nervousness, and lack of coordination rather than through genuine maliciousness. If a rabbit bites young children because they have hurt it, they are likely to retreat and teach the rabbit that biting is an effective defense. To prevent this, young children should be allowed to interact with rabbits only under direct supervision of an adult. They should not be allowed to pick up the rabbit. Instead, they should interact with the rabbit on the floor or a couch, if the rabbit is comfortable jumping on and off the couch. Mini and dwarf rabbit breeds may be at greater risk for injury by children than are larger breeds.

Steps in Introducing a New Rabbit
• Begin by placing the rabbits side by side in separate cages to allow them to become familiar with the sight, sound, and smell of each other without being able to fight. If one or both rabbits exhibit aggressive behavior (e.g., rushing the cage wall nearest the adjacent rabbit), move the cages farther apart until the behavior does not occur. Gradually move them closer together until their cages touch. This stage may require several days.

• The next step is to introduce the rabbits under supervision. Having each rabbit on a harness and leash makes it easy to separate them if a fight starts. Familiarize each rabbit, individually, with the harness and leash before beginning this phase. Most rabbits freeze the first time a harness is placed on them. If they are allowed sufficient time to become accustomed to the harness, they eventually move—at first tentatively and then normally. Having the rabbit on a lawn with patches of clover or other desirable greenery can facilitate progress.

• When both rabbits are comfortable on a harness and leash, take them to a neutral area (i.e., a location where neither rabbit is routinely allowed to be loose). Ideally, one person should supervise each rabbit. Allow the rabbits to approach aiid investigate each other. If neutral or friendly behavior or ritualized dominance without aggression (e.g., one rabbit places its head over
the other rabbit) is exhibited, do not interfere. If one rabbit attacks the other, calmly pull back the aggressive one. It is important not to overreact (e.g., forcefully pulling an attacking rabbit could injure it, and yelling could increase both rabbits' anxiety). If this cannot be accomplished at home, it may be helpful for veterinary technicians or other animal health care or behavior professionals to conduct the initial introduction. Rabbits that invariably fight at home under owner supervision have successfully learned to interact amicably when brought to the University of Georgia's behavior service examination room (i.e., a novel environment that does not require territorial defense by either rabbit). Place various foods and toys around the room to attract each rabbit's attention. If the rabbits appear to be ignoring each other, do not force interactions. The rabbits are aware of each other's presence and will interact with each other when ready.

• When the rabbits interact well while supervised on leash, remove the leashes and allow the rabbits to roam freely in the same room with supervision. Fights can still erupt at this stage. If the rabbits begin to fight, use . a towel to gently separate them. If the rabbits continue to interact well, allow them to roam freely in areas other than the one in which they were initially trained.

Behavior Modification of an Aggressive Rabbit
• Wear sturdy, protective clothing such as solid shoes, thick denim pants, and heavy leather gloves (such as those used in handling aggressive dogs and birds of prey).

• Sit quietly near the rabbit. If it charges or bites, continue to sit quietly.

• Once the rabbit has stopped attacking, offer it delicious treats (e.g., carrot, apple, banana). Moving away when the rabbit is calm and quiet can also help in some cases.

• Gradually interact with the rabbit, pet it, and play with it. Eventually, carefully pick it up and hold it securely. This process may take several weeks for a rabbit that developed fear aggression due to painful and/or fear-inducing experiences.

• When the rabbit has been rehabilitated, ensure that it does not have experiences like those that caused the initial problem.

If a rabbit has developed fear aggression, behavior modification should be conducted by an adult who is not afraid of the rabbit. Although experienced rabbit owners may be comfortable doing this, professional assistance may be necessary. Rabbits that have learned to defend themselves through aggression must learn not to be afraid of humans and that biting humans does not make them go away (see box at left).

If species-specific behavior and principles of learning are understood and applied in the management and care of pet rabbits, behavior problems can be easily prevented and treated.

1. Pongracz P, Altbacker V, Fenes D: Human handling might interfere with con-specific recognition in the European rabbit (Oryctolagus cuniculus). Dev Psychobiol 39:53-62,2001.