Sunday, 8 August 2010
An exciting discovery with a sad twist
I came across the most incredible spider at the farm this morning. The abdomen was about 1.5 cms long and from the tip of the front legs to the tip of the back legs was about 5.5 cms. That is some BIG spider! I was able to identify it from the Collins Field Guide to Spiders as Argiope bruennichi, known as the Wasp Spider. It's a female, full of eggs. That zig-zag ribbon of silk is called the stabilimentum - there are several theories as to its purpose.
In Europe this species is locally distributed in France, Germany and the Low Countries. Following the first British record in 1922, it is apparently now well established in locations near the English south coast and is spreading northwards. The females make their webs in long grass, often near field edges, and that's just where this one was.
An internet search for "Cornwall spiders" led me to www.stevehopkin.co.uk, a real enthusiast's resource where you can download a distribution map for every species found in the county. The map for the Wasp Spider shows only seven locations where it has been recorded, the nearest being on the Fal estuary. Coverage throughout the county is patchy but the Lizard and West Penwith have received more attention than most other areas.
I noticed that the maps haven't been updated since April 2006. Another search and I was shocked to learn the reason why. Steve Hopkin was killed in a road accident the following month. He had been a senior lecturer in zoology at Reading University, a scientific associate in entomology at the Natural History Museum in London and was the spider recorder for Cornwall. What is especially poignant is that the biography on his website is still in the present tense. A work in progress was abruptly and tragically terminated.