As I was closing in on the spot I planned to start fishing on Saturday I came across a odd sight! A man waking downstream with a antenna. The project he was involved in was looking at how salmon migrate in river Ätran.
They had caught 45 salmon last year and put a transmitter on them, since then they had been following those salmon. There were some fixed checkpoints put up in different places along the river but they where also “strolling” the river bank with a antenna. With the the fixed points they could see how far up the system fish where moving and with the hand held antenna they could pinpoint the fish. Now in early April they were looking at fish mowing out to sea again, and what surprised me is that he found the fish was still in the river! In Ätran it seems as most of the spring flood has already passed with last weekends water level at over 110m³, now has dropped to 60m³ – I thought the fish were following the flood into the sea – but instead it seems last years spawning fish is still somewhere in the river system. Maybe the river temperature has something to do with it? Last weekend river was in about +1° C and this Saturday river temperature had risen to +5° C ! maybe fish is waiting for a optimal temperature to return into sea?
The project is a part of the river management, next year the hydro power plant closest to sea is supposed to bee remodelled – this will bee done by opening the original canal and let the river and migrating fish take that way instead of going trough the dangerous turbines! But as it is with those project it is not yet certain whether it will bee delayed or if it will go as planned.
They had caught 45 salmon last year and put a transmitter on them, since then they had been following those salmon. There were some fixed checkpoints put up in different places along the river but they where also “strolling” the river bank with a antenna. With the the fixed points they could see how far up the system fish where moving and with the hand held antenna they could pinpoint the fish. Now in early April they were looking at fish mowing out to sea again, and what surprised me is that he found the fish was still in the river! In Ätran it seems as most of the spring flood has already passed with last weekends water level at over 110m³, now has dropped to 60m³ – I thought the fish were following the flood into the sea – but instead it seems last years spawning fish is still somewhere in the river system. Maybe the river temperature has something to do with it? Last weekend river was in about +1° C and this Saturday river temperature had risen to +5° C ! maybe fish is waiting for a optimal temperature to return into sea?
The project is a part of the river management, next year the hydro power plant closest to sea is supposed to bee remodelled – this will bee done by opening the original canal and let the river and migrating fish take that way instead of going trough the dangerous turbines! But as it is with those project it is not yet certain whether it will bee delayed or if it will go as planned.
While looking for salmon moving out to sea he found a majority standing right downstream the hydro power plant – it might bee a sign of fish going through the turbines and not in the intended passes.
Unfortunately I got the chance to see the consequences of fish passing through the turbines later in the day, a fellow fisherman caught a kelt with massive damages! Half the upper jaw was torn of from passing the turbines – the fish was put back but I think this one will have a hard time surviving at sea.
In river Emån there is a project with one of the power company's, to build a safer passage for the downstream migrating fish – this project was put in place last year and has been working fairly good! This year some improvements is supposed to be done and hopefully it will work – if it does work, and fish is passing beside – instead of through the turbines I hope this solution will be used in all the places where the hydro power plant is viewed as a necessity!
A few interesting fact though;
Although there is some man maid obstacles – and because of that man maid passes for salmon – one salmon had been spotted more than 60 km upstream !
Another salmon had been found in a small stream less than a meter wide at spawning time! - I thought sea trout was using the small streams and salmon in the bigger once...
Although there is some man maid obstacles – and because of that man maid passes for salmon – one salmon had been spotted more than 60 km upstream !
Another salmon had been found in a small stream less than a meter wide at spawning time! - I thought sea trout was using the small streams and salmon in the bigger once...
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