Emile Azran stands in the sun in front of his sardine processing factory in Safi, Morocco, smoking a cigarette. Business is slow because it is the Eid holidays but soon he says the chimneys will be pumping at full steam again. The smell is putrid.

Sardines, once cheap foodstuff for the poor, have become a popular dish in Morocco. Mr. Azran’s factory, Almev, takes discarded sardine heads, tails and entrails from the canneries along the row at Safi and turns them into protein-rich animal feed. The flour-like substance is mixed with other feed and served up to contented chickens, turkeys, sheep and cows across Morocco.

The factory employs a workforce of 20 men. It is not work for the faint-hearted. The men spend hours a day knee-deep in sardines, shovelling them onto a conveyor belt, pressing water and oil out of the gloop and working alongside furnaces that fire at 1600°C. Most of his employees come from poor families, Mr. Azran tells us, and he runs the business as a social enterprise.

He describes the history of the sardine trade in the Atlantic over the last 100 years. As the cooler waters of the northern ocean have shifted south, temperature-sensitive sardine shoals have followed. The sardine industry has pursued the fish, moving down through Portugal and Morocco. Today the shoals have moved on again, passed Safi. The majority of the fishing fleet is now based further south in the Western Saharan ports of Laayoune and Dakhla.

Mr. Azran is sure that global warming has caused the migration of the sardines but is confident that it will not affect his business. For the moment, at least, the specialist knowledge and technology for processing the fish remains in Safi.  But the industry at Safi is completely dependent on the supply of sardines. If competition in the south makes it uneconomic for ships to continue delivering their catch, the industry will be forced to uproot again and follow the cooler waters and sardine shoals south.