The most important food fish in the world and one of the most numerous vertebrate in the world can be found in the Atlantic and Pacific oceans, as well as in inland lakes. The silver of the sea has been harvested for ages and used for food, oil, fertiliser, animal feed, and bait. It has become less numerous through overfishing, but the stock has stabilised after most countries involved started monitoring and restricting the fishing.
The herring family is called clupeidae, and also includes shads, sardines, and menhadens. The fish are small and thin, and always shimmering. The most common colours are a dark one above, brilliant silver on the sides, and white below. Herring spend most of the time in deep water, then migrate to shallower coastal waters where they lay their eggs. Their schools may encompass millions, which swim close together near the water surface.
The herring's main food source are small crustaceans. They themselves are also the main food source for many, such as whales, seals and sea birds. A common way to find the shoals for fishermen are spotting the many birds that hover over them. Looking for reflexes from the shining fishes is also useful, but these days echo sounders are common.
The most important kinds to the fishing industry are Pacific and Atlantic herring, which can be found in their respective oceans in cold to temperate areas. Russia and the United States catch most of the Pacific herring, while Canada, Denmark, Iceland, Norway and Sweden are leading countries in harvesting the Atlantic one. | 
