Why would the ability to predict the occurrence of el nino be important for the fishing industry on the western coast of south america?

The fishermen who handle the waters of the Pacific off the shore of Peru and Ecuador have known for a considerable length of time about the El Niño. Each three to seven years amid the periods of December and January, angle in the waterfront waters off of these nations basically vanish, making the angling business grind to a halt. South American anglers have given this wonder the name El Niño, which is Spanish for "the Boy Child," since it happens the season of the festival of the introduction of the Christ Child. Amid an El Niño, the physical connections between wind, sea streams, maritime and environmental temperature, and biosphere separate into dangerous examples that are second just to the walk of the seasons in their effects to climate conditions the world over.

El Nino is known in coasts of Peru and Ecuador.
Every 3 to 7 years (in the months of December and January), this phenomenon occurs causing the fish to virtually disappear or vanish from the water. This leads to a deterioration in the fishing industry.

Being able to predict El Nino would help fisher men a lot as it will give them an idea of when this phenomenon will occur. Therefore, they would be able to plan for the season accordingly as they would know when to expect the disappearance of the fish from the coasts.

Hope this helps :)