Do big tides encourage salmon to run ?

[elwyman]

I'm not convinced myself, and was interested to see this on one of the Annan web sites:

"A feature of the past few days, to be continued into the first half of next week, has been the abnormally high tides - some 5ft over and above the average spring tide. People have been asking whether the spring tides bring in the salmon runs, and I have to say that although that might seem to be a logical result, in reality over the years it has been the medium tides that usually brought in the salmon , as low tides are of little assistance and high tides stir up the Solway causing hundreds of tons of sand to collapse from the channel sides. This in itself murks up the water, but when combined with high winds such as we have had the past few days, makes for a very turgid sea at the rivers mouth - not at all pleasant for the salmon waiting in the estuary to run. "

[elwyman]

I'd agree with that Graham.

I think what happens on some of the N Wales rivers is that we get a flood (like this week on the Conwy) and all the fish in the estuary run up, When the big tides arrive a few days later, there's no fish left in the estuary and the anglers all feel disappointed!

I also think on smaller rivers, high tides at dusk or at night are more likely to get fish moving, particularly if the river is low.

[severnfisher]

During normal river conditions I would expect a spring tide phase to induce a run of fish into the Severn. The bigger the spring tide the better as it makes Tewkesbury weir at the top of the tidal influence less of an obstacle. Unlike the Solway rivers the Severn has a very long tidal and semi-tidal section before you get down to the estuary proper. Severn Bores always produce a run of fish unless there has been a significant rise just before.