Aha, this may have answered the question I was searching for answers for before starting a new thread. I have a trio of yellow terribilis (from Mworks, great frogs, plug over) that are just over a year old. I've noticed the biggest of the three occassionally calling when one of the others comes into contact with it, it's happened now and again for the last three or four months, but it's becoming more regular. Could this be a female telling the boys where to go?