young dwarf brothers one-sided fights

Question
Hello, I recently adopted two 2-3 week old Campbell dwarf siblings from a woman who had accidentally bred more. At first I thought one might be female because it seemed to not have as developed testes (the little "butt bags") and was on the receiving end of mating advances (that it clearly received as attacks, from all the squeaking and cowering later on), but the two appear to be anatomically similar. I moved the larger one and have tried reintroducing them to eachother, mostly in the smaller one's cage where he is "dominant". They still fight. Is it possible that the smaller one is female? Should I assume they just can't get along, and try to trade the attacking one for another sibling? I'd rather they live together as it is easier to have one cage, and Campbells are a social breed and will live longer together. Thank you for your help!

Answer
Hi Maya

Hamsters should not be separated from their mother until they are around 3-4 weeks old, and I never home them until they around 5-6 weeks old.  If you adopted them at 2-3 weeks, then this is very young and perhaps they haven't received some of the socialisation they would have received had they stayed with their mum for longer.

Whilst Campbells can live together - once they reach adulthood - around 4 months - often their personalities change and they can become more aggressive.

Obviously one important thing is to check their sexes, or you could end up with a litter.  Is there any way you can get them checked out?  Pet shops are sometimes helpful, or a local vet could confirm this.

With regard to them living together, unfortunately sometimes they just can't.  There is clearly some sort of territorial power struggle going on.  If you want to try and re-introduce them, I would suggest the following:  keep them in their separate cages for now, but every day swap them over for a few hours - so they are in the other one's cage.  This way, they will keep smelling each other.  After a week or two of doing this, assuming they are both settling down, you could try putting them together - however, I would advise you do this in comletely neutral territory.  If you can borrow another cage that would be good - or use a large cardboard box - you must be able to get to them quickly if they start fighting.  Closely monitor them for a while, then if they are OK put them together in the cage.  I would suggest that before you put them together in the cage you clean it thoroughly so that neither scent is in it - this way they are both on an equal footing.

It is difficult to know if this will work - if it doesn't then you may have to accept that they will need to live out their days in their own cages.

Hope this helps you - let me know how you get on.

Regards
Sheila