The relationship between invertebrate densities, current velocity and water depth was studied in the Dan River, northern Israel. Maximum current preferences ranged from 5-120 cm set -', and depth preferences ranged from 5-60 cm. Thirty-five taxa of invertebrates were collected by means of colonization cages. Larval and adult stages of 3 Elmidae (Coleoptera) species were treated separately: Limnius letourneuxi, Grouvellinus caucasicus and Elmis rioloides. Differences in current preference were observed between larval and adult stages of the same species of Elmidae. Taxa were also grouped according to preference for turbulence. Wide ranges of depth and current velocity preferences were observed. Most of the taxa were found at between 80-100 cm set -I and at depths of less than 30 cm. A correlation between species diversity and current velocity was established. Velocities of 60-80 cm set-' contained the greatest overlap of faunal preference. The sensitivity of selected species to stream flow reduction is discussed.

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