How to introduce my guinea pig?

Britney has the right idea, I wanted to add that you should only put on of the original guinea pigs with the new one, so the other piggies won't try to team up against the newbie. ^_^

best way is to have them in two separate hutches, and have them a few meters apart so they can still see each other, then every few days to a week, slowly move hutches closer until they are right next to each other, then start having "play dates" just a few minutes a day.

You can make any guinea pigs friends some just take a tad longer than others.

Don't be alarmed if they start chasing each other, as they are just sorting out rankings.

Also another great idea is to get them all desexed so there is no hormonal interference.

Quarantine!!!!

Quarantine!!!!

Especially if your new one was abandoned. You have no idea if its carrying any illnesses of diseases.

Put him in a seperate cage on a different floor of the house if possible. If not, then atleast in another room. Keep him there for atleast 2 weeks. I highly suggest taking him to the vets too-just to be safe.

Then when thats all done, swap their cages. Put the two in his cage and him in their cage for a day ect. Do this for about a week. It allows them to get used to eachother's scents and then they will smell very similar.

Then you can go ahead and put them in a neutral area. Have a towel at the ready. If they fight, throw the towel over them and seperate.

Try again in a few days time-keep swapping cages.

After about 2 weeks of them being introduced in neutral ground, completly clean out the hutch. Wash it, disinfect and move everything around-so its like a brand new cage. Add guinea pigs and supervise for atleast 1 hour. You need to be sure they won't fight.

Keep in mind that you will see a range of behavior:

Safe, non-combative, dominance behavior

Rumblestrutting

Butt sniffing

Butt nudging

Chasing

Butt dragging (they are leaving their scent)

Mounting (any which way: rear mount, head mount, side mount, flying leap mount!)

Nose face-offs (higher in the air wins, one must lower their nose to be subservient to the other)

Teeth chattering: a little (signal of dominance)

Raised hackles (hair on the back of the neck and along the spine)

Posturing for possible attack, battle for dominance is escalating

Teeth chattering: sustained (signal of anger, aggression, warning)

Nips, light bites, may result in little tufts of fur in their teeth

Wide yawn, but this is no yawn, they are showing their teeth

Snorting (like a strong puff or hiss)

These behaviors may sound serious and they should be monitored VERY CLOSELY, BUT do NOT separate the pigs exhibiting this behavior, yet. This is when the average pet owner loses it and pulls the pig out. Most of the time, this behavior will continue for a while until one backs down.

Fighting with intent to harm

Bite attacks are no longer warning nips, they are lunges with intent to harm.

Combination of raised hackles, loud and angry teeth chattering, rumblestrutting in place with the head staying in one position while facing the other guinea pig doing the same thing. Usually a signal of a biting attack. But they may back down before they engage.

Both pigs rear up on their haunches, face to face. This is a clear, brief signal of their intent to launch full attacks at each other. Separate if possible before the attack.

Full battle. The pigs are locked together in a vicious ball of fur. This is very serious. Separate immediately, but be careful. Throw a towel over them and use a dustpan or something other than your hand to separate them. Unintended bites from their very sharp incisors can cause serious damage.

Guinea pig and Companionship - http://jackiesguineapiggies.com/Companionship.html