Middle-term changes in caddisfly (Trichoptera) communities of the Hungarian part of Dráva river during the years 1992-2004

113 species are known from the Dráva region. All the collections were quantitative. Some sites were examined during a longer period (i.e. middle term), thus the change of caddisfly communities or collectives are to be studied. The longest and most complete series of data is from Vízvár, the most abundant caddisflies of this site are presented and analysed.