I am new to this forum but have been keeping and breeding reptiles for about 30 years (since I was a little kid). I am based in the UK and last year acquired a trio of Cunningham's skinks - I say trio but apart from knowing one of them is 100% male, I am unsure of the others. The male is 6 years old and the unknowns 4 years old.
A bit of history for you - the male was a single animal that had lived alone all his life. The other two grew up together and had never been apart (no issues ever observed between them). They were introduced into a single enclosure in Autumn 2012 and were watched closely (I am aware of the potential for aggression). The definite male proceeded to sniff out the other skinks and went about chasing one of them while gently nipping the tail and flanks. After a couple of days it calmed down and they have all been living in harmony ever since - no fighting or bickering at all.
I have spoken to a couple of breeders (one who has kept this species for many years) and he is of the opinion that they must be 1.2 because otherwise I would have a dead skink on my hands. Another breeder says he has managed to keep reverse trios but only if they are raised together from a very young age. Apparently it is extremely hard integrating adults into a colony and generally better off raising them together from a very early age. Be that as it may I seem to have got away with it.
I am aware that physically this species is very hard to sex and I only know one is definitely male because the hemipenes have been clearly sighted in addition to sperm plugs.
They did not breed last year, but I am trying a different approach this season and can only hope for the best.
I would like to ask experienced E.Cunninghami keepers/breeders about their experiences and the likelihood of my having at least one of each gender.
Also, while we are about it, for how long do you E.cunninghami breeders brumate your animals? Have you experimented with different periods and if so what were the results? I am especially interested in feed back from non-Australian keepers as a lot of you lucky people in Oz get to cheat by using outdoor enclosures

Thanks in advance.
Adam