In October 2022, EV-INBO and TIIAME tagged 29 snowtrouts in Shakhimardan to track their movements and habitat use at the demo site before the construction of the hydropower installation. Although the manufacturer estimated that the tags would last one year, which was enough for our study, about ten are still active!

This provides an excellent opportunity as it provides us extra data, particularly in spring, as that proved to be the period that snowtrouts migrated over 10 km downstream for reasons we are still analysing. Therefore, scientists from TIIAME are still going to Shakhimardan regularly to track the snowtrouts. In addition, another 30 radio transmitters have been ordered and will be surgically implanted in the snowtrouts the coming spring to continue the tracking experiment. The goal of this following tagging experiment is to study if the hydropower installation and activation has an impact on the snowtrouts returning to the River Koksu after their downstream adventures.

We are currently analysing the tracking data that has been collected so far and in general, we observed that the snowtrouts move downstream in spring and early summer, but migrate back upstream in late summer and autumn.

Author and picture credits: Pieterjan Verhelst, EV-INBO