[helene schoubye]

Actually, I sometimes have the same problem with my ‘own’ offspring. I have species which produce a very uneven number of the two sexes, – in particular p. harveyi. Most of the offspring are males. And of course, I also reflect over this situation that I think one or more factors are ‘wrong’ – and I am trying to figure out which and change it.
So of course it really makes sense what you are writing Peter, – that one could worry that enviromental changes could have this effect on the fishes in the habitat.
That sounds very worrying.