SAVE OUR SALMON!

[Anglers' Net]

News release from the Salmon and Trout Association

 

Click here to view the full article

[Worms]

News release from the Salmon and Trout Association

 

Click here to view the full article

Signed

[Jaffa]

News release from the Salmon and Trout Association

 

Click here to view the full article

 

It may or may not be true that salmon farms are causing the decline in west coast stocks.

 

What is true is that this piece from the article is spin;

 

Mr Knight continued: “Over the last decade there has been a wealth of research in both western Scotland, some of it conducted by Scottish Government scientists, and in other salmon farming areas overseas which has shown conclusively the devastating damage that sea lice emanating from the farms cause to runs of migrating wild salmon and sea trout. The only practical solution is to move the farms away from the most important estuaries”.

 

There has indeed been a lot of research done in Western Scotland by UK scientists; which have not found a link, but there has also been a "wealth" of "research" by interested parties in North America which claim to have proved one.

 

Its a nice spin to merge the two for political gain but thats about all it is IMHO.

[Brian Carragher]

Jaffa

 

I remember this lice topic last time it was aired and I don't think it was properly explained.

 

How do lice which are present in any given area of sea and which for this purpose I'm assuming that the fish in the farms have lice seeing as they're in the sea, have any affect on returning fish as presumably they have to swim in the same lice affected waters in order to enter the river systems

 

The lice will be there regardless of wether there are fish farms or not so any fish either farmed or naturally returning will be exposed to the same amount of risk

 

Lets hope our journalist friend does'nt read this as it would be a shame to see another good topic turn t*ts up

[Worms]

Jaffa

 

I remember this lice topic last time it was aired and I don't think it was properly explained.

 

How do lice which are present in any given area of sea and which for this purpose I'm assuming that the fish in the farms have lice seeing as they're in the sea, have any affect on returning fish as presumably they have to swim in the same lice affected waters in order to enter the river systems

 

The lice will be there regardless of wether there are fish farms or not so any fish either farmed or naturally returning will be exposed to the same amount of risk

 

Lets hope our journalist friend does'nt read this as it would be a shame to see another good topic turn t*ts up

The lice don't really affect the adult fish returning to spawn. Even if they did pick them up they wouldn't last very long in fresh water. The risk I believe is that immature salmon going to the sea for the first time pick them up and, being smaller are more susceptible to infestation than bigger fish.

 

The fact that the sea lice are present in relatively high concentrations at salmon farms would automatically imply a greater risk to the immature fish.

[barry luxton]

These fish that are penned, surly they can be treated for virus and parasites etc. If so what is the problem?

[Worms]

These fish that are penned, surly they can be treated for virus and parasites etc. If so what is the problem?

There are a lot of treatments on the market, some work well....too well, they also affect other marine organisms. Some are difficult to administer such as de-lousing baths (for obvious reasons) some are added to feed (how do you guarantee an effective dose is eaten by each fish? or if too much is eaten it could poison the fish). Another problem is that sea lice are very adaptable and have proved very able at developing resistance to some of the treatments. I dare say cost is a factor as well.

 

A lot of work is ongoing both abroad and in the UK.................

[Worms]

It may or may not be true that salmon farms are causing the decline in west coast stocks.

 

What is true is that this piece from the article is spin;

 

 

 

There has indeed been a lot of research done in Western Scotland by UK scientists; which have not found a link, but there has also been a "wealth" of "research" by interested parties in North America which claim to have proved one.

 

Its a nice spin to merge the two for political gain but thats about all it is IMHO.

 

Not quite true, some of the UK and Scandinavian research has shown connections. The following are quoted from:

Wild sea trout Monitoring – Loch Feochan 2006, Alan Kettle-white Argyll Fisheries Trust

 

"The salmon louse Lepeophtheirus salmonis is a naturally occurring parasite of wild salmon and sea trout. However, its abundance in some areas has increased dramatically in recent years (Tully et al. 1993a,) due to increased host numbers in the form of caged salmon, present in coastal areas throughout the year"

 

"Sea trout are probably more vulnerable to louse infection than salmon since they remain in inshore waters where most fish farms are located, and where lice larvae are most abundant. Salmon, in contrast, move rapidly out to sea. Although sea trout kelts can be badly affected by lice, it seems post smolts are most at risk due to their smaller size and the physiological stress associated with recent transfer to seawater. Research suggests that more than about 12 mobile lice for salmon smolts and around 25-30 for sea trout smolts can cause stress to the hosts and skin lesions which can lead to a failure of the fishes’ ability to regulate its water balance (Finstad et al. 2000: Grimnes & Jakobsen 1996). The fish will die unless the lice are removed or lost. The lethal infection level will vary with fish size, larger fish generally being able to tolerate higher levels of infection than smaller fish."

Edited August 6, 2009 by Worms

[Jaffa]

Jaffa

 

I remember this lice topic last time it was aired and I don't think it was properly explained.

 

How do lice which are present in any given area of sea and which for this purpose I'm assuming that the fish in the farms have lice seeing as they're in the sea, have any affect on returning fish as presumably they have to swim in the same lice affected waters in order to enter the river systems

 

The lice will be there regardless of wether there are fish farms or not so any fish either farmed or naturally returning will be exposed to the same amount of risk

 

Lets hope our journalist friend does'nt read this as it would be a shame to see another good topic turn t*ts up

 

Hi Brian,

 

In the middle of several days of very long shifts, so apologies for not replying as yet. Try going to have a look for this "wealth of evidence" if you want

 

Worms, thx for the heads-up.

 

Chris

[Jaffa]

There are a lot of treatments on the market, some work well....too well, they also affect other marine organisms. Some are difficult to administer such as de-lousing baths (for obvious reasons) some are added to feed (how do you guarantee an effective dose is eaten by each fish? or if too much is eaten it could poison the fish). Another problem is that sea lice are very adaptable and have proved very able at developing resistance to some of the treatments. I dare say cost is a factor as well.

 

A lot of work is ongoing both abroad and in the UK.................

 

Agree with almost everything you say there Worms, but the bit about lice developing resistance is a new one on me; is that genuine comment based on something you have actually read or done about salmon lice or is it just your assumption that since its been shown plenty of times before in intensive farming, then it must be true for salmon farming?

 

 

Chris