[Derek Roxborough]

A pal gave me a Fishing News (Aug 2018 pg 2) with an article by a Norwegian Scientist how the proliferation of Mackerel is affecting the salmon, larger Mackerel predating on smaller smolts and competition for food, another idea about salmon decline, it's the first time I heard of this , it seems possible though, Derek Roxborough

[Rob Brownfield]

I think the over fishing of sandeel, capelin, anchovies, sprats and so on will have forced mackerel to seek a new source of food.

After all, salmon and mackerel have co-existed together for hundreds of thousands of years without an issue.

Mans  demand for fishmeal (56% goes into feeding aquaculture..mental!) has cost the oceans and the oceanic food chain dearly!

We are currently removing a whole layer of food that is affecting larger fish, sea birds, sea mammals and ultimately, us. Taking 5kg of small fish to create 3kg of fishmeal to deliver 1kg of Salmon on a plate is unsustainable.

[Derek Roxborough]

I think the over fishing of sandeel, capelin, anchovies, sprats and so on will have forced mackerel to seek a new source of food.

After all, salmon and mackerel have co-existed together for hundreds of thousands of years without an issue.

Mans  demand for fishmeal (56% goes into feeding aquaculture..mental!) has cost the oceans and the oceanic food chain dearly!

We are currently removing a whole layer of food that is affecting larger fish, sea birds, sea mammals and ultimately, us. Taking 5kg of small fish to create 3kg of fishmeal to deliver 1kg of Salmon on a plate is unsustainable.

yes Rob it always has been, the whole Industry has proved that sustainability is the last thing it needs, Derek Roxborough

[Derek Roxborough]

I think the thing about the article is that it hasn't been looked at scientifically before, Mackerel have probably been targeting Smolts in the past, but not to the extent that there is an Impact on the salmon stocks, the Mackerel thing may also be a factor in the seatrout problem , Derek Roxborough

[Andy MacArthur]

Mackerel, and their habit of  hanging around automatically fed cages systems are undoubtedly a vector of transmission of Caligus sp.
 The smaller of the two salmon lice species.

[Robert MacDonald-Lewis]

I assume smaller Mackerel would be on the menu for larger Salmon, would there not therefore be some benefit to Salmon in larger stocks of Mackerel?