low numbers of hoverflies due to heat - like F**k

Ha!. The moment I moan about low numbers of hoverflies due to the heat. I visit Top Llan (Gilfach (west) and the place is dripping with them, 1/2 dozen on each flowering hogweed plant and there are 200+ plants in bloom. I recorded 35 species with 1000+ flies present. The three species I wrote about in the last blog were all present in high numbers. Episyrphus balteatus a passage migrant largely absent until now was streaming in from a southerly direction and moving along the lanes. Conservative estimate 75 flies. Eristalis pertinax numbered 40 and Syritta pipiens numbered 260 but that was to be expected. Other species seen that were either first for the year or have been scarce this summer were Melanostoma mellinum, Melanostoma scalare, Platycheirus albimanus, Eupeodes latifasciatus, Syrphus ribesii (30+), 6 species of Cheilosia, Eristalis rupium (female), Eristalis tenax, Sericomyia silentis, Volucella pellucens, Platycheirus granditarsus and Helophilus trivittatus. Why so many, well the mist and light rain has brought out the surviving damp/water species and the rain has also seen an explosion of aphids for the species that feed on them at the larva stage so adults were frantically laying eggs.

 aphids on Hogweed were numerous to say the least

 Helophilus trivittatus

 Sphaerophoria scripta

 Eristalis tenax

Platycheirus granditarsus