Abai, MR

6th International Congress of DipterologyThe environmental requirements of Sciomyzidae (Diptera)on turloughs in the west of Ireland with particular referenceto the role of mollusc host/prey communities.Williams, C.D. (1) & M.J. Gormally (1)(1) Applied Ecology Unit, Centre for Environmental Science, National University ofIreland, Galway, Ireland.Turloughs which are temporary water bodies unique to Ireland, are listedas a priority habitat in the European Union Habitats Directive (1992).Recent work has focused on carabids, but less attention has been paid toDiptera on turloughs. Fifty-two species of the family Sciomyzidae(Diptera), all of which have malacophagous larvae, occur in Ireland.Skealoghan turlough was selected to determine within-site variation ofsciomyzid species across a range of vegetation zones. Ten sweeps (5m) ineach of six homogeneous vegetation zones were taken weekly (2/6/04 –29/9/04) in addition to a number of environmental variables. Theunivoltine Ilione albiseta was dominant, but species displaying a range oflife history traits were also present. Results suggest that sciomyzidcommunities are specific to particular turlough zones with even adjacentzones having different communities. Key environmental determinants ofsciomyzid community composition and abundance appear to be vegetationheight and hydroperiod of the zone. A wider study on 24 zones across tenturloughs was conducted to determine between-site variation. Samplingmethods followed those of the intensive single-site study, with the additionof mollusc surveys, which were undertaken at the same sampling locationsduring the flooded winter period to elucidate the role of host/preycommunities. Again, Ilione albiseta dominated the catch and theimportance of vegetation structure and hydrology was evident, suggestingthat flooding regime and grazing during the dry phase are of majorimportance. Additionally, a method for partial regression analysis ofspatial, environmental and larval resource variables for the most abundantspecies is presented.302