(posted on my Lasius flavus, Lasius niger and Messor barbarus journals)
So...I've just had my first death...or should I say ten deaths - including my only four queens. I'm afraid I can't say it was some unusual mould or a careless young relative, it was entirely my own fault. I'll try and go through it quite quickly so I can better understand myself what I did wrong, I don't get too guilty, and hopefully other newbies can learn from my stupidity.
They had been sitting wrapped up in a cloth, in a tub, beside the radiator, in the living room, and the thermometer sitting on top of the cloth was usually about 22C. I received a heat mat today and frankly didn't have a clue what to do with it except to move ants onto it out of the living room before Mum finally realised what was in the tub. I took the cloth out of the tub, set it on the heat mat (unsure if this was safe, even unsure if it was the right way up or if that mattered), and set the thermometer on top of the folded cloth again. The heat mat was on half power or so, I think. After a while, the temperature was 25, so I went off to watch Game of Thrones. Returned several minutes ago to check on them and...they were mainly upside down with their legs in the air. I have taken the tubes off the mat and unplugged it, and they're sitting in the tub with the cotton unplugged in hopes that one queen may not be completely dead, but it's a vain hope. The four niger workers had attached themselves to the cotton plug, so one or two workers seem to be okay, but they'll live pretty bad lives if the queen doesn't recuperate.
I feel an incredible fool, it just didn't occur to me that the test tubes would be any hotter than the thermometer. I will not be trying any new colonies for a while, until the guilt seeps out - maybe, hopefully, Easter.
So - when introducing anything new to your ants, do it gradually, observe their reactions, and check what those might mean (for example, sticking themselves to the cotton plug).