Plankton babies

Copyright: Gavin Parsons. All rights reserved

This week’s Behind the Picture is a bit of an odd one. While working on a survey of the plankton in the Mediterranean Sea I was asked to photograph some of the specimens the vessel collected.

This had to be done before the samples were sealed ready to take to the laboratory. Basically when the plankton net was hauled aboard the sample in the back of the net was poured into a chemical preserving agent. Before that I was given a small amount in a glass dish and asked to photograph whatever was in it.

One of the key species being looked at was the Blue Fin tuna, one of the world’s rarest fish. Adult fish fetch huge sums of money in the fish markets of the world. The reason is the complete disregard for the species by fishing nations. The fishery for blue fin tuna is an utterly disgusting race to the bottom with pure greed and profit as the driver for the trade. Because the less fish there are in the sea the higher profits.

There is an unseen fleet of tuna purse seine vessels that roam the Mediterranean, particularly around Malta and Cyprus catching as many fish as possible. They are then fattened up in massive seapens, which generally means they are caught too small to have bred. In my opinion it is one of the most stupid fisheries in the world.

Knowing the number of juveniles is particularly important for scientists trying to advise governments on how best to safeguard the species. So tuna were the target. We found quite a few other juvenile fish species in each sample, lots of eggs which can be identified in the lab back on shore and of course a lot of zooplankton species such as copepods, which only get to a few millimetres in size.

Every so often a tuna species did turn up, (you can see one on the middle of the three fish in the picture) but not in the numbers I’d hoped for. It was, to my untrained eye, quite a depressing sight seeing as so few juveniles make it to adulthood. Even so I photographed each sample that was produced. It wasn’t easy as the ship was moving and I didn’t have the option of a microscope as this was being done of the fly at the back of a working ship. Around me were coils of rope, bins, tools, chains and all manner of industrial paraphernalia. It was not where most scientific photographers would like to work.

I strapped all the extension tubes I had between the camera and my 105mm macro lens. I didn’t have a tripod as when I joined the ship I had no idea I’d be doing this kind of photography. Luckily I did have my off camera flash radio control so could get the light right where I wanted it.

I sat the glass dish on a black t-shirt to get a dark background and then set up the exposure with the flash. It was then a case of shifting my movements up and down ever so slightly to get the samples in focus when I pressed the shutter.

To start with there was a lot of trial and error and most of the pictures were slightly out of focus, but eventually I managed to get a technique, which improved my technique.

I thoroughly enjoyed this adhoc scientific photography session and soon I’ll be looking to do some more, but with a much more scientific and controllable set up.

To see more of my work, book on a training course, buy a print or book my for a talk please see my website at www.gavinparsons.co.uk

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