THE HOVERFLIES (SYRPHIDAE) OF BROMESWELL GREEN NATURE RESERVE A . C.
HUBBARD
This Suffolk Wildlife Trust Reserve is situated on the eastern bank of the River Deben a few miles north of Woodbridge. It consists of a number of diverse habitat types within a relatively small area (19.5 hectares). The areas of herb-rich grassland with associated wet flushes and areas of sedge constitute the most important habitat for syrphids. Flowers of Marsh Marigold (Caltha palustris) provide a food source for spring emerging species and there then follows a succession of flowering plants throughout the summer, including Wild Angelica (Angelica sylvestris), Common Fleabane (Pulicaria dysenterica) and Water Mint (Mentha aquatica), all particularly favoured by hoverflies. Areas of woodland and scrub are comparatively recent in origin, but there are some good standards of Oak and Ash, mature Alder coppice and an understorey of Hazel coppice and Holly in some areas. Scrub species include Willow, Blackthorn and Bramble, the catkins of the former are again particularly valuable to spring emerging species. Other habitat types include reedbed, brackish marsh and freshwater streams. Recording of hoverflies has been carried out by the author over the last ten years, more comprehensively since 1985, and a total of 63 species has been identified. Notes on the more interesting species are set out below, followed by a complete species list for the reserve. Nomenclature follows Stubbs and Falk (1983). Platycheirus fulviventris Recorded occasionally in areas of brackish marsh; described as local in the county (George, W. S. & Aston, A. E., 1960) Pyrophaena granditarsa and P. rosarum P. granditarsa was not seen on the reserve until 1989 whereas P. rosarum has always occurred regularly. Both species occur in wet meadows with lush vegetation; the latter has also been noted along rides through Alder coppice. Chrysogaster chalybeata All three species in this genus have been recorded on the flowers of umbellifers. C. chalybeata has been noted on one occasion only; it is described as scarce in the south east of the country (Stubbs, A. E. & Falk S. J., 1983).
Trans. Suffolk Nat. Soc. 27 (1991)