Sneaker, Dweller and Commuter: Evaluating Fish Behavior in Net-Based Monitoring at Hydropower Plants—A Case Study on Brown Trout ( Salmo trutta )

Nicole Smialek, Joachim Pander, Arne Heinrich and Juergen Geist
Additional contact information
Nicole Smialek: Aquatic Systems Biology, TUM School of Life Sciences, Technical University of Munich, Mühlenweg 22, 85354 Freising, Germany
Joachim Pander: Aquatic Systems Biology, TUM School of Life Sciences, Technical University of Munich, Mühlenweg 22, 85354 Freising, Germany
Arne Heinrich: Aquatic Systems Biology, TUM School of Life Sciences, Technical University of Munich, Mühlenweg 22, 85354 Freising, Germany
Juergen Geist: Aquatic Systems Biology, TUM School of Life Sciences, Technical University of Munich, Mühlenweg 22, 85354 Freising, Germany

Sustainability, 2021, vol. 13, issue 2, 1-20

Abstract: Monitoring of fish passage at hydropower plants largely relies on stow-fyke-net captures installed downstream of turbine outlets, yet little is known about which fish behavior contributes to reduced catch efficiency. We studied fish-net interactions as well as biological and physical factors potentially influencing behavior in three experiments: (i) fall-through experiment, to measure the general physical ability of a fish to fit through a certain mesh size; (ii) net-perception experiment, where fish were filmed while being exposed to different mesh sizes, flow and lure conditions in a controlled arena setup; and (iii) stow-fyke-net experiment, where fish behavior was recorded using 20 cameras simultaneously inside a stow net during regular hydropower fish monitoring. In total, we analyzed 382 h of video recordings. The material revealed that fish interacted with the net on a high rate, independent of flow conditions, and tried to swim through the mesh regardless of whether their body fits through. Under field conditions, the fish showed three specific behavioral patterns, “sneaking,” “dwelling” and “commuting,” which led to a reduced recapture rate in the catch unit of the stow-fyke net. This study highlights the importance of considering fish behavior in future fish monitoring programs to improve the accuracy of turbine-effect assessments on fish.

Keywords: hydropower; fish escapes; environmental assessment; fish behavior; net fishery; fishing method (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2071-1050/13/2/669/pdf (application/pdf)
https://www.mdpi.com/2071-1050/13/2/669/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:13:y:2021:i:2:p:669-:d:479036

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().