Interfering with nature...

[The Woodman]

Does this not depend on the provenance of the broodstock?

If they are taken from the river in which the ova / fry are to planted for whatever reason -mitigation stocking or populating nursery areas upstream of obstructions then the genetic stock will not be affected.

Using ova from other sources can introduce genetic traits not best suited to the particular river system.

[zan]

I'm sure you're right - I don't know a lot of the current details as it has been a while since I studied freshwater systems. But it also means that there is no natural selection for ova \ larvae that are just poor survivors (even if taken from the same river stock) as they are nursed through this stage of their lives.

My point really was that even well-intentioned interference can have detrimental impacts that may not be apparent for a long time.

[The Woodman]

Yes - on the greater scale of things, who knows what man's interference might produce.

The hot topic at the moment in fisheries is the EA's Trout and Grayling Strategy, in particular the effects of introducing sterile triploid brown trout into our rivers, but that's a subject not for this thread.

Throughout history in Cumbria, many of the lakes and tarns have been stocked with non indigenous strains and species of fish without regard to their or their habitats future. Over time, nature has a great way of putting things right if left alone by man.

For example, not too many years ago a batch of Norwegian Salmon ova was reared to fed fry stage at a hatchery and released into a major north west salmon river. Unthinkable today, but at the time, the best science didn't oppose the initiative.

The escape of farmed salmon and their subsequent effect on wild stocks is of some concern, but when it happens it's too late to do anything about it except for the (never used in Britain yet) Norwegian total river wipe out method usually used to control parasites.

Detrimental impacts can be short term as well, with a long term natural resolution.

[zan]

Absolutely agree, and thanks for the info on Grayling \ brown trout - I'll look that up. Anyway, at the risk of completely hijacking this thread, I'll let it return to topic Apologies for the diversion!

[The Woodman]

Likewise, apologies FUDGEY!

[Jenny W]

Originally Posted by Adam Cheeseman

As far as the law goes it's all about intentional disturbance, whatever the reasoning, sentiment doesn't come into it.

Cheers,

Adam

Yes I know that thanks (I know the law - I've worked with nesting birds often enough), what I actually meant was (and apologies for not expressing myself very well) that as the laws are there to protect against intentional damage/interference etc. I see it as a bonus if it protects against ignorance as well - please let me know if I need to explain it better.

[FUDGEY]

Interesting comments from both sides of the fence. In my defence I would not lift eggs that were newly laid. These eggs were hours from hatching. The birds that nest earlier sometimes make it before the big tides, but for some reason they all were later than normal this year. A few have said that if I did leave them the birds would learn, but I have not done this for many years now and they obviously still havent learned. Oystercatchers, Redshanks and Ringed Plovrs are dwindling fast in my area and if I can save a few then I am content with my actions.