What does fishing down the food web mean?

Fishing down the food web is the process whereby fisheries in a given ecosystem, “having depleted the large predatory fish on top of the food web, turn to increasingly smaller species, finally ending up with previously spurned small fish and invertebrates”.Click to see full answer. Moreover, how does fishing affect the food chain?“Overfishing can have an adverse effect on marine biodiversity. Overfishing can [also] wreak havoc and destroy the environment and marine ecology and completely disrupt the food chain. For example, herring is a vital prey species for the cod. Therefore, when herring are overfished the cod population suffers as well.Secondly, what is the food web of the ocean? Phytoplankton are microscopic producers that form the base of all ocean food webs. In addition, sea grass and seaweed cover the floor of the Great Barrier Reef. Thousands of primary consumers eat the producers. Small tropical fish, sea urchins, sea stars, crabs, shrimp, and clams consume the plants and phytoplankton. Regarding this, where are fish on the food chain? At the bottom of the food chain are microscopic plants and at the top are well-known predators like sharks and seabirds. Depending on their size and place within the food web/food chain, fish serve a variety of purposes and help to balance the ecosystem in many ways.Are anchovies secondary consumers?Large fish are omnivores, secondary consumers, and eat kelp and small fish. Small fish can be firefish and anchovies. Some sea urchins eat dead animal matter which also can make them decomposers.