Guinea pigs sniff each other’s bottoms for several reasons. It allows them to identify members of their own species, determine compatibility, and determine whether the other guinea pig is dominant or submissive. Guinea pigs sniff one another’s bottoms to gather information about each other.
Have you ever wondered why certain animals, including guinea pigs, sniff the bottoms of their peers who are just getting to know them? Did you ever think you would be intrigued by this question enough to warrant an internet search?
Well, you’re in the right place, because I have to! Here are some answers to possible questions you might have.
Is Sniffing Behavior Normal?
As long as nothing wrong results from guinea pigs’ butt-sniffing (such as a fight), you can say with certainty that this is a perfectly normal, safe, and healthy activity.

Sniffing is part of a ritual animals partake in to get to know each other. However, if you notice they don’t seem to like each other and engage in violent behavior, you will need to act (I will explain this a little later).
For the most part, bottom sniffing is a cute and harmless behavior. Several guinea pigs can even form “sniffing trains,” in which they line up with their noses at each other’s rear ends. That is especially “aww” inducing!
Why Do Guinea Pigs Sniff Each Others Bottoms?
To Identify Members of Their Own Species
Most creatures, including mammals and humans, emit pheromones, hormone-like chemicals that allow community members to distinguish between familiar and unfamiliar companions.
This ultimately allows for survival because complementing scents spell safety in numbers. In contrast, unfamiliar scents represent a threat to that safety.
That is probably why guinea pigs who detect an unfamiliar scent will become defensive or aggressive toward a new playmate. Their natural instincts will kick in to protect their territory and lives at whatever cost.
To Determine Reproductive Compatibility
Guinea pigs sniff each other as part of a mating process. Males will sniff females to find out if they are capable of reproducing via the complex system of pheromones I mentioned earlier.
Part of this process may include the female spraying urine to attract mates, as urine carries a pheromones profile of its own.
But keep in mind that this can also be a sign of pigs resisting mating, which leads back to your role of conscious observer to make sure curious exploration doesn’t get out of hand.
To Determine Dominant and Submissive Pigs
No matter their species, animals will keep out those who do not fit in with their group and would negatively affect the group’s functioning.
Generally, the submissive submits, and the dominant takes offense. This can occur between the young and old, male and female, and piggies with varying degrees of temperament.
Some guinea pigs might take well to being sniffed; others might see it as intrusive and fight back.
Dominance and submissiveness are both survival instincts and happen unconsciously, so piggies may act unpredictably even when they display harmless behaviors like sniffing.
You must pay attention to the personality of each pig if you plan to keep more than one together and provide a safe, comfortable, and low-stress environment in which companionship can flourish.
Now that you understand the basics of sniffing and what it entails, let’s look at what we can do to help guinea pigs become tolerant companions.
How to Introduce Guinea Pigs Safely
Put Them in a Neutral Environment
Ideally, this is a place neither pig has experienced before, where they won’t be distracted by familiarity and won’t venture into unfamiliar territory.
Do not put them in a cage together right away. Close proximity too quickly does not allow for natural relationship building to take place.
Choose a place with minimal furniture so that the guinea pigs can’t hide behind or under it. Also, it should be large enough for the pigs to retreat to if they get frightened during introductions.
Pigs should be placed on towels that don’t smell like other pigs. Provide food so pigs can experience eating together.
Do Not Interfere
There may be some need to nudge pigs toward one another, but otherwise, let introductions proceed as if they were occurring in the wild. Do not rush introductions. You may have to wait a while.
Monitor Behavior Closely
It is normal for Guineans to nip each other occasionally. If the nipping gets frequent and/or draws blood, you will have to intervene. Use a towel, oven mitt, or anything you can think of to protect your hands as you move them away from each other. If they fight, throw a towel over them as an interruption.
Signs of aggression also include:
- Teeth chattering
- Snorting
- Leaning back on haunches (position to fight)
- Biting
- Showing teeth
Separation may need to happen, and introductions can be repeated another day. Be mindful that one or more of the pigs may have an underlying condition that makes them resistant to bonding and address it. Don’t give up!
Watch for safe and friendly behavior as well. These are all part of the dominance and submissive ritual that naturally occurs to help pigs get used to each other.
Friendly behaviors include:
- Mounting (normal for both sexes)
- Teeth chattering (a lot of it!)
- Chasing
- More butt sniffing and nudging
- Popcorning (moving around quickly in all directions like popcorn)
- Rumble strutting (walking side to side and making rumbling noises. This is a common mating behavior in male pigs.)
- Nose lifting (pigs raise noses in the air to see who is highest and therefore more dominant.)
Stay in Control
Bottom sniffing is just one part of an entire process of behaviors designed for pigs to trust each other, seeing as they might be with each other in the same place for a long time.
It’s completely normal, but in some cases, it may escalate. You will need to know what to do to prevent injuries. Don’t worry too much, though, as you are in control of the situation.
Enjoy the sights of funny-looking bottom sniffing and other entertaining behaviors. These are some of the best parts of owning guinea pigs. Good luck!