Tag Archives: flies

Insecticidal Maniacs?

2 Jun

I’m spending part of the summer dyeing dance flies at a nature reserve near Loch Lomond. Yesterday’s flies were electric blue. Today’s were day-glo orange. Tomorrow they will be lemon yellow. After dyeing them, I’m releasing them back into the wild. The high visibility will allow me to recognise them if I recapure any of them the following day.

On my first day, my supervisor Dr Luc drove me and my assistant to the site and showed us the areas we are to work in, and how to carry out the research project in a sufficiently scientific manner. We are working with gigantic fly nets, which we swing maniacally around our heads whenever our swarm convenes. Each fly captured in the net goes into an individual phial.

If you go down to the woods today

After half an hour of frantic net-swinging, it’s time to sex and dye the flies. Each one is checked for gender, dropped into a vial of dye, given a shake, and released. The vegetation is soon adorned with brightly-coloured dance flies. Some of them take to the air straight away, and look very pretty in the sunshine. Others prefer to clean themselves first.

Fly dyeing

The university’s Health and Safety rules say I must have an assistant for field research, because my ability to walk varies. Katydid is perfect for the job: she’s as batty about wildlife as I am, and strong as an ox. She carries all my stuff – lunch, water, spare jumpers, survival gear, seventy-odd vials, paintbrushes, wooden stakes, hammers, forceps, chocolate, jars of ethanol… you name it. Even though I had hoped the university would loan me a donkey to carry my stuff, I have to admit that Katydid makes a very decent pack-horse.

Malaise trapThe jars of ethanol are for the malaise traps. As well as painting flies, we have set up traps on the reserve to assay the insect life. I can’t say I am delighted about this part of the project, as it’s essentially mass murder – but the results can be fascinating and useful. Flying insects are trapped and preserved in jars of ethanol hanging from the tent-like structure in the photo above.

This is a personal test for me, to explore how far I am able to stretch my powerful moral boundary about harming animals. I need to know if I can make this a part of my future career in Zoology. We are carrying out our mass murdering in a protected area that’s not open to the public, and we have special dispensation to do it. The idea is to provide ecological organisations with information about the species present on this land, while at the same time gathering information about dance fly prevalence for the university. I am self-justifying my killing in terms of its assistance towards preserving biodiversity.

A prevalence of electric-blue dance flies

I was pleased to learn that Dr Luc also has moral feelings regarding invertebrate death and suffering. He and his colleagues display genuine affection for the creatures they study. I don’t find this attitude much in the human world: non-fluffy things with lots of legs are generally considered fair game for cruelty. My childhood role model was the conservationist Gerald Durrell, a self-styled “champion of small uglies”.

It helps me to know that the “small uglies” we trap won’t be flung in the bin when we’re done with them. Dr Luc is not wasteful about death, and he keeps all malaise-trapped insects for future entomological projects. Some of his students are going to spend hours at the microscope, dissecting the ovaries of pickled flies the size of pinheads. I think Gerald Durrell would approve.