Welcome to the forum
How long have you actually had them?
It’s not that he has a short temper - mounting, chasing, rumbling are all normal dominance behaviours.
When you move piggies to a new environment, they go into a two week period of reestablishing their relationship and hierarchy (this happens even if they have always been together). This increases the dominance behaviours.
It also increases due to teenage hormones. Piggies are teenagers between 4 and 14 months of age
Squeaking and running away is submission which is good and the correct response.
However a dominant piggy who won’t let up can be a sign of a potential issue.
While behaviours remain normal dominance, you have to just let them get on with it. If you intervene unnecessary then you can do more harm than good.
If they were to have an actual fight then the bond would immediately be over and they would need to be separated and live side by side.
Is their cage big enough?
Two boys need a lot of space and a cage measuring 180x60cm which converts to 70x24 inches is needed.
You also need two of everything in the cage.
Make sure all hides have two doors. Any hide with only one door can cause problems if they both get in there together and the door gets blocked off.
The guides below offer more in depth information about boars, their needs and what to do if you were to suspect their bond isn’t working.
Reacting to group or territorial changes: Dominance and group establishment/re-establishment
Bonds In Trouble
A Comprehensive Guide to Guinea Pig Boars
Boars: Teenage, Bullying, Fighting, Fall-outs And What Next?
Dominance Behaviours In Guinea Pigs
