Anchovy

The anchovy sits at a pinch point in the ocean food web. It is one of the main fish that eats plankton directly and packs that energy into an oily, protein-rich body, which is then eaten by nearly every larger ocean predator, including tuna, cod, salmon, seabirds, seals, dolphins, and whales. When anchovies are abundant, those predators breed well; when anchovies crash, seabird colonies fail and fish stocks thin. On top of that ecological role, the anchovy is the raw material for most of the world's fishmeal and fish oil, so it also feeds the farmed salmon, shrimp, pigs, and poultry that people eat. Few fish carry so much of both the natural and the human food system.

They are the same family and often the same species, but in a very different state. Fresh anchovies are mild, soft, and delicate, eaten fried whole in Mediterranean and Japanese cooking and nothing like the intense little fillets on a pizza. Those come from anchovies packed in salt for several months, during which enzymes break down the flesh, the bones soften, and the flavour concentrates into the sharp, savoury, umami taste that defines them. The same cured anchovy, melted into a sauce or dressing, disappears completely and leaves only a background richness, which is why it is a hidden ingredient in Caesar dressing, Worcestershire sauce, and many braises.

Both are small, silvery, oily schooling fish that filter plankton and are heavily fished, but they are different families and easy to tell apart up close. An anchovy has a pointed, overshot snout with the mouth set well back and low, giving it a distinctive shark-like underbite, a single dorsal fin, and a slender body with a bright silver stripe. A sardine, which is a type of small herring, has a blunt, rounded snout with a terminal mouth, a deeper body, and rows of dark spots along the flank in some species. In cooking, sardines are meatier and milder, anchovies smaller and much stronger, especially once cured.

The anchoveta lives off Peru and Chile because of a powerful upwelling that brings cold, nutrient-loaded deep water to the surface and drives an enormous plankton bloom. Every few years an El Nino event pushes warm, nutrient-poor tropical water over that coast, the upwelling shuts down, the plankton fails, and the anchovies either die, stop breeding, or move away, so the fishery collapses within months. The most famous crash, in 1972, came from an El Nino on top of heavy overfishing and took years to recover. Modern management tries to soften this by closing the fishery quickly when surveys show the stock or the ocean conditions turning, but the boom-and-bust pattern is built into the system.