Posted by Graeme Lyons , Saturday, 20 August 2016 09:42
Somewhere along the South Downs Way in deepest West Sussex is a small and isolated yet rich and diverse site managed by the Murray Downland Trust called the Devil's Jumps. So named for the sequence of five Bronze Age barrows that rise up from the site and have a rich chalk-grassland flora. Last weekend I started the fifth of sixth surveys there with Mike Edwards and it wasn't long until I swept what I initially though was a washed out Sphecodes. Then Mike became REALLY excited and shouted that's Andrena marginata! We hadn't even got close to the barrows at this stage and as we approached I saw the grassland was so dominated by Small Scabious that it only took seconds to find another two females. All in all we saw five females in total. Although currently considered nationally scarce (Na) this bee is one of the most declined bees in Europe and is therefore a hugely significant find for the survey. As the bee is only taking pollen from Small Scabious, its pollen baskets are white. Quite unlike the other rare bee on scabious, Andrena hattorfiana, which has pink pollen baskets from the Field Scabious/Greater Knapweed that it feeds on.
We went on to Heyshott Down itself and despite masses of Small Scabious, there were very few bees there at all. However, almost every flower of Wild Carrot had one of these wasps on it being Tiphia femorata. We also saw several Nomada flavopicta. Three new aculeates for me in one day! I'm up to 330 species for the survey so far and I still have all Mike's idents, my idents and this month's notes to write up!