"Research project on the (re)establishment of grayling (Thymallus thymallus) in the Mid-reaches of the River Kamp".

The grayling (Thymallus thymallus) is a key species of the middle reaches of Austrian streams but is acutely threatened or disappeared in many streams. In the middle reaches of the Kamp River, the morphological conditions for grayling habitat are given, but there is no possibility of immigration due to a chain of dams in the headwaters and the absence of the species in the lower reaches. In the present project, a reintroduction of genetically autochthonous material from the upper reaches, hatched with innovative near-natural conditions in river water, is investigated. A mobile fish breeding container is erected and the eggs are hatched separately according to families. The different families will be stocked as eggs into artificial nests or as juveniles to compare different stocking methods. In addition, artificial spawning sites will be poured to monitor the homing of the stocked egg and juvenile stages. In parallel, the required flow regimes will be modeled to maintain the functionality of the spawning sites and to develop a sediment management concept. By means of annual success controls the development of the population will be investigated and by means of genetic methods the different stocking strategies will be compared.