Warning signs

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Changes in the body fat of mackerel may give a clue to a factor in the decline of wild salmon. So argues Dr Martin Jaffa in his latest column for Fish Farmer.

A new study from the University of Aberdeen funded by pelagic fishermen, yet to be fully published, has found that from around 2010, there has been a sharp decrease in the body fat content of caught wild mackerel.

Why does this matter to salmon conservation? Because if changes in the marine environment are impacting on mackerel, they may also affecting salmon survival rates.

Read the whole article, starting on page 24, online here in the September issue of Fish Farmer.