Fish- ecological evaluation of the Thaya
In September 2006 and April 2007 an outdoor survey of the fish stock along
the Austrian and Czech area of the Thaya at Hardegg, Laa/ Thaya and in
the estuary area between Břeclav and Hohenau was conducted. The fish sampling
was performed in correspondence to the guide of measurses of the Austrian
Federal Ministry of Agriculture, Forestry, Environment and Water Management
(BMLFUW).In accordance with the different types of waterbodies multiple
fish sampling measures were applied:
pic.: Mud minnow (Misgurnus fossilis)
- in areas with a water depth of < 0,7m two consecutive courses of estimations using the wade- fishing- method, as one type of electric fishing by means of specific technical equipment were conducted,
- deeper river areas have been fished via strip- fishing method from the boat,
- in the bayous the examinations were conducted by structure-oriented Point-Abundance-electric fishing and additional fish sampling by using nets.
Furthermore grain size analysis of the spawning ground of litophilic fish species and the rate of eclosion using fish spawn boxes were performed.
The results of the fish- ecological examination of the Thaya
will be integrated to a dataset, which functions as basis for the evaluation
of
the ecological
condition of the river according to the national “Fish Index Austria” (FIA)
method.
Project
part-financed by the European Union (ERDF)