The professional use of cutting-edge technology such as scientific echosounders and sonars (hydroacoustics) to answer new questions in applied freshwater fisheries science has steadily increased in recent years. For some areas of interest only hydroacoustic methods deliver an appropriate ability for precise and non-invasive responses to a range of issues.

      The Fisheries Association Westphalia and Lippe e.V. has been working in this field since 2001. The LFV Hydroacoustics Corp. was sourced out as a spin-off company in 2011.
The use of non-invasive hydroacoustic technologies and related know-how is a matter of course in our scientific and practical work. Prerequisites for successful investigations are state-of-the-art hardware, practical skills and expertise in data assessment and analysis.

      Depending on the question and issue, different technologies can be applied. With scientific single and split-beam echosounders in mobile applications it is possible to assess the spatial and temporal distribution of fishes and their abundance. In combination with common methods like gillnetting it is also possible to estimate the biomass of fish stocks. Stationary applications for enumeration (fish tracking and counting) are also important fields of work. Additionally, investigations on submerged vegetation, bottom classification and habitat bathymetry increase steadily.

      The Dual-Frequency Identification Sonar (DIDSON) is an outstanding tool for in situ observations of fishes and their behaviour. This „Acoustic camera” represents cuttingedge technology within the area of multi-beam imaging sonars and generates video-like images independent of light level and water turbidity. Therefore it can be used in both mobile and stationary modes, especially at locations where optical sensors (like common video cameras) fail. The DIDSON offers capabilities to observe and investigate fish migration, fish behaviour e. g. at hydropower stations and related bypass systems, weirs and comparable barriers and bottlenecks, technical up- and downstream migration facilities (fish ladders), and active/passive fishing gears.