Over a period of several months (from May to September 2008) the presence of Odonata was ascertained in three brooks within the municipalities of Eberndorf and Sittersdorf . These brooks are the Kotschuschabach Seebach and the Suchabach with a few of its tributaries. With the help of various maps samples were taken from each of the 27 test sections. At the same time the biotic and abiotic conditions of the brook itself and its environment were determined as well as the damselflies (Zygoptera) and dragonflies(Anisoptera)which were found along the test sections. Altogether 26 species of Odonata were found. Each brook of the examined area shows signs of different hydromorphological grades, which frequently change within the course of one an the same brook. The test sections were carefully chosen, so they allow sampling in all possible grades. The distribution of Odonata, respectively their proportional distribution, shows great variation within the examined area. Whereas several species of Odonata exist side by side in the Kotschuschabach and in the Seebach, this is only true for one section in the Suchabach. The evaluation of the findings revealed that upstream, from 9.2 section, Odonata no longer exist. While damselflies are completely absent past U 9.2, dragonflies turn up again upstream from U 13. A closer inspection of the hydromorphological conditions supplied possible causes of the disappearance of damselflies. This strech of water is located in Gösselsdorf and includes the test sections U 9.2 and U 9.3. This embankment is extremely controlled: both bottom and banks from U 9.1 as far as U 9.4 are both highly reinforced. This, as well as further cross-constructions upstream, may act as a barrier which makes it difficult, particularly for damselflies, to migrate along the brooks serving as guidelines. The migration and with it the spreading of damselflies might consequently fail as they show the least airworthiness amongst all the Odonata.