Introducing and Bonding a Second Chinchilla

Quick answer

Chinchillas live in colonies in the wild, and many pet chinchillas are happier with company. That is not the same as saying any two chinchillas will accept each other, and it is not a reason to put a new animal into an existing cage and hope.

A settled pair sits close, eats at the same time and rests in the same hide. That is the destination, and it is usually weeks or months away from the first meeting.

Introductions go wrong for a small number of predictable reasons: they are rushed, they happen in the resident's territory, resources are not duplicated, or the pair is left unsupervised too early. Chinchilla fights escalate in seconds and produce deep puncture wounds that seal over and abscess.

• Quarantine the new chinchilla properly first, in a separate room, with a veterinary health check before anything else happens.
• Introduce through a barrier for weeks before they ever share a space, and swap cages and scents in the meantime.
• The first shared space must be neutral, and the permanent cage should be new or stripped and thoroughly cleaned so neither animal owns it.
• Duplicate everything: hides with two exits, water bottles, food bowls and hay stations.
• Some pairs never bond. Side-by-side cages give social contact without the risk, and that is a legitimate outcome rather than a failure.

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Never separate fighting chinchillas with your bare hands.

Chinchilla incisors are long, sharp and powerful, and a chinchilla in a fight bites whatever it contacts. Use a thick towel, a folded blanket or a piece of stiff card to interrupt and divide them, and wear gloves. Do not grab either animal by the fur, because fur slip will release a patch of coat and leave you holding nothing while the fight continues.

After any fight, examine both animals thoroughly. Chinchilla bite wounds are small punctures that close over quickly, trapping infection underneath, and the abscess appears days later. Any bite wound is a same-day veterinary matter even if it looks like nothing.
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Decide in 60 seconds

Why introductions fail

The resident's cage is not neutral.

This is by far the most common mistake. A chinchilla's cage is its territory, marked with its own scent, containing its own resources. Placing another animal inside it produces a defence response, and first impressions in this species are durable.

They were rushed.

People work to a weekend rather than to the animals. Barrier contact for a few days is not enough. Weeks of living alongside each other, with cage swaps and scent mixing, is what builds a neutral association before the first meeting.

Resources were shared rather than duplicated.

One hide, one water bottle, one food bowl and a single narrow shelf all create points of conflict. A dominant animal that can control the only water bottle will control it.

The layout had dead ends.

A hide with one entrance is a trap. A narrow shelf with one way off is a trap. A subordinate animal that cannot get away is an animal that has to fight.

The combination was difficult.

Two adult females who did not grow up together, an adult and a kit, or two animals with a large size difference are all harder. Siblings raised together are the easiest, and everything else is a spectrum from there.

They were left alone too soon.

Everything can look settled for an hour and then change. Nothing about a chinchilla introduction is safe unsupervised until you have watched them share space, eat together and sleep together repeatedly.

Something was medically wrong.

A chinchilla in pain from dental disease is short tempered, and an animal incubating an infection is not in a state to negotiate a new relationship. This is why the health check comes first.

Before anything else: quarantine

Separate room, separate air if you can manage it.

Respiratory infection moves easily between chinchillas, and the new arrival is coming from a shop, breeder or rescue where it has been mixed with other animals.

Separate everything.

Own cage, own hides, own food and water containers, own dust bath. Never share dust between animals during quarantine, because ringworm travels in it.

Own hands.

Deal with the resident first, then the newcomer, and wash your hands and change or cover your clothing in between.

A veterinary health check.

Ask for the teeth to be examined, for the skin and coat to be checked for ringworm and parasites, for the chest to be listened to, and for the sex to be confirmed. Sex is mis-stated often enough that it is worth paying a vet to confirm it, and the consequence of getting it wrong is a litter.

Give it real time.

Quarantine long enough for an incubating illness to declare itself. Ask your vet for the period appropriate to where the animal came from. Use the time productively: settle the newcomer, get it eating well and holding weight, and learn its normal behaviour.

The introduction process

Duplicated resources and hides with two exits are what stop negotiation turning into a fight. Set this up before the animals ever share a space.

Stage one: cages in the same room, apart.

Once quarantine is complete, move the cages into the same room but far enough apart that neither can reach or touch the other. They see and hear and smell each other and nothing else happens.

Stage two: cages closer, but never touching.

Bring them nearer over days, keeping a gap of several centimetres so that noses, toes and tails cannot reach through both sets of bars. Bars pressed together cause bitten toes and torn ears.

Watch what they do. Sitting calmly near the barrier, sleeping on the adjacent side, and eating with the other in view are all good. Persistent barking, spraying, lunging or chewing at the bars means back off and give it more time.

Stage three: swap scents and swap cages.

Swap hides, fleece and toys between the cages. Then swap the animals themselves, so each spends time exploring the other's cage while the other is elsewhere. This matters more than most owners expect, because it separates the smell of the other chinchilla from the idea of an intruder.

A shared dust bath, offered to each in turn once quarantine is over and both are confirmed healthy, mixes their scent efficiently.

Stage four: supervised meetings on neutral ground.

Use a space neither animal has been in, or one that has been thoroughly cleaned. A play pen, a cleared bathroom, a puppy pen in the middle of a room. Provide two or more hides with two exits each, and something to eat.

Keep the first sessions short. Stay in the room for every second of them. Have a towel and a board within arm's reach before you start.

End the session while it is still going well, rather than waiting to see what happens.

Stage five: a shared cage that neither owns.

Once meetings are consistently calm, move them into a new cage, or into the old one completely stripped, scrubbed and rearranged with new or thoroughly cleaned furniture. Nothing should be in the layout it was in before.

Duplicate every resource: at least two hides with two exits, two water bottles at opposite ends, two food bowls, several hay stations, and wide shelves that can be left in two directions.

Stage six: supervision, then more supervision.

Stay with them. Then check frequently. Then check often. Do not leave them unattended overnight until you have seen them eating together, resting together and sleeping in contact repeatedly over days.

Weigh both animals daily through this period. A subordinate animal being quietly excluded from food shows up on the scale before it shows up in behaviour.

Reading the behaviour

Watch the posture rather than the noise. A loose, mobile animal that keeps eating is negotiating. A stiff, upright, staring animal is about to escalate.

Normal and acceptable.

Mutual sniffing, especially nose to nose and around the rear. Rearing up on the hind legs facing each other. Short chases that end. Urine spraying, most often a female rebuffing a male, which is a refusal rather than an attack. Some noise. Brief, mild fur pulling.

Grooming each other, sitting in contact, and using the same hide are the signals you are working towards.

Stop the session.

Rapid teeth chattering with a stiff, upright, staring posture. One animal repeatedly cornering the other. One animal that cannot get away. Prolonged chasing with no pauses. Either animal refusing to eat in the other's presence.

Separate immediately.

A rolling ball of fighting animals, screaming, fur flying in quantity, or any blood.

Afterwards, in the shared cage.

Check both animals daily for bite wounds, especially around the ears, feet, tail base, shoulders and genital area. Check for fur chewed off the back of the neck and between the shoulders, which only the other animal could have done. Check that both are eating hay and both are producing normal numbers of droppings.

The routine that keeps a new pair safe

What never to do

Do not put a new chinchilla into the resident's cage.

Do not skip quarantine because the newcomer looks healthy.

Do not push two chinchillas together to let them sort it out. They do not sort it out, and chinchilla fights cause injuries within seconds.

Do not use your hands to separate fighting animals, and do not grab either one by the fur.

Do not push cages together bar to bar. Toes, tails and ears get bitten through the mesh.

Do not leave a new pair unsupervised because the first hour went well.

Do not house a male and a female together unless the male has been neutered by an exotics vet and the interval the vet specified has passed.

Do not attempt an introduction during hot weather, while either animal is unwell or recovering, in the days around a house move, or with an animal that has untreated dental disease.

Do not introduce a young kit to an adult without expert advice about the size and age difference.

Do not dismiss a small puncture wound. It seals over and becomes an abscess.

Do not keep pushing a pairing that has produced a genuine fight. Some animals can be reintroduced very slowly from the beginning, and some cannot.

When to get help

A successful bond looks like two animals resting in contact, eating at the same time, and both holding their weight week after week.

Contact an exotics veterinarian the same day for any bite wound on either animal however small, for any bleeding, for a chinchilla that will not leave a corner, and for either animal that has stopped eating or is producing fewer or smaller droppings.

Contact one urgently for panting, lying flat, drooling or bright red ears, which point to overheating, since introductions involve chasing and excitement and a hot room turns that into an emergency.

Book an appointment before you start for a health check on the newcomer, including the teeth, the skin and confirmation of sex, and again if a previously settled pair begins fighting, because pain, dental disease and illness change social behaviour before they change anything else.

Bring the age, sex and weight history of both animals, how long each has been in the household, the stage of the introduction you had reached, a description of what happened, photographs of any wound or fur loss with a note of where it is on the body, the cage dimensions and layout, and the room temperature. Where an introduction has broken down, the layout and the resource count usually explain more than the temperaments do.