SALMON ON THE RISE
For years - since the last century all back to the 60'ties - it has been claimed, that the salmon will not pass Forsjordio in Vefsna until the water-temperature is at least 8 degrees Celsius, and the river doesn't run with more than 320 Cubics/second.
An assumption that has no bearing in reality, and I will prove it wrong this very moment:
Look at the statistics for 2021, from June the 9.th til July the 15-th.:
Blue line is salmon rising
Orange line is temperature 10 AM
White line is cubics/second (which must be counted times 10 - though)
Grey line is the tendency of the water level
Let's first look at the temperature, which only once from June the 4.th throughout the period was below 8 degrees Celsius: on June the 16.th.
But from May the 15.th to June the 18.th Vefsna ran with far more than 320 Cubics/second! It started rising on the 10.th of May and was of course very cold then.
If the mentioned assumption would have been right, the Salmon would only be able to run through Forsjordio from the 18.th of June and then run through Fallan and all the way to Laksfors in at least one or two days - which is very unlikely.
But from the 9.th to the 21.st almost 40 salmon went through Laksfors!
Some might propose that the 40 salmon had gone up Forsjordio before the waterlevel went above the mentioned 320 Cubics/second early in May - but then the temperature was at the highest 7 degrees Celcius and even went down to some 4 degrees in 10 days from the 12.th of June and onwards.
Finally, by June the 25.th some 100 salmon had passed Laksfors!
In other words: the salmon will go through Forsjordio even when temperature is below 8 degrees Celsius - and/or the water-pressure is above 320 cubics/second!