Why are there usually huge schools of fish near zones of upwelling?
Water in upwellings is warmer than surrounding water.
Upwellings support fewer currents, so it is easier for fish to swim.
Upwelling brings nutrients to the surface.
Cold water from upwellings supports more fish.
The correct answer is: Upwelling brings nutrients to the surface.
Upwelling occurs when deep, nutrient-rich waters rise to the surface, replacing the warmer surface waters. This cold water is rich in nutrients like nitrogen and phosphorous, which are essential for the growth of phytoplankton, the base of the oceanic food chain. The phytoplankton bloom that occurs as a result of upwelling draws in zooplankton, small fish, and other organisms, which in turn attract larger fish. This is why upwelling zones are usually teeming with life and support diverse fisheries.