Another small rise today on upstream beats following yesterdays rain which was obviously rather more significant than seemed probably from local rain, though yet again the highest catchment around Llangurig seemed to miss it completely.
Its only about nine inches or so and not so dirty as the Ithon water previously but hopefully will assist any running fish which are still conspicuous by their abscence on upper river beats.
Any of you hopefully responding to the NRW consultation might be interested in the summing up on hatcheries below. It does I think give credence to the SNR project which the majority of people support.
As long as salmon have been managed there has been a biological
argument against hatchery fish. Some of the concern is emotional and some is
legitimate. Introduction of non-local hatchery stocks often show little or no
sustained success. Of course that would be true of non-native wild salmon introductions as well. If the genetics of the fish are out of phase
with the environment, they will fail. The more pervasive concern is the idea
that introductions will compromise the native gene pool. There are arguments for
and against that thesis, and the scientific literature has not been helpful in
resolving the issue. Understandably, if non-native fish are introduced, theory
tells us they can have negative consequences, but if local fish are hatchery
propagated there is no evidence that the local population would experience
anything other than improved productivity. Biologists are divided on that issue,
but few studies on long-term effects of hatchery fish on their parental
population have been undertaken.
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