The construction of the nest was probably the most interesting stage to observe. Small teams of wasps would land on the fences in my garden (for some reason they tended to favour certain patches of fence) and they would scratch away at the wood. The act of scratching was audible from some distance away and also left lots of thin lines scratched into the fence which are still there several years on. The wasps would then fly back to the paper-like nest and add the chewed wood pulp to the outer layer of the nest.
In order to photograph this activity I decided that I wanted to use my MP-E 65mm macro lens in order to get sufficient magnification. The downside of this plan was that this lens has a maximum working distance of only a few centimetres meaning I had to get very close to the nest. Every now and again I would get slightly too close and would brush the nest with my flash diffuser. This would result in numerous wasps exiting the nest en masse in order to see off the perceived threat. It would also result in me moving in the general direction of away, quite rapidly :-)
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A Median Wasp exiting the nest
Nest building: in the image below you can see the recently chewed wood pulp that has been added to the nest
The image below shows what happened if I accidentally knocked the nest. Bear in mind my face was just a matter of centimetres from the wasps...!