Shoaling and schooling

In biology, any group of fish that stay together for social reasons are shoaling (pronounced /ˈʃoʊlɪŋ/), and if the group is swimming in the same direction in a coordinated manner, they are schooling (pronounced /ˈskuːlɪŋ/). In common usage, the terms are sometimes used rather loosely. About one quarter of fish species shoal all their lives, and about one half shoal for part of their lives.This copepod has its antenna spread (click to enlarge). The antenna detects the pressure wave of an approaching fish.Copepods are a major food source for forage fish like this Atlantic herring.School of herrings ram-feeding on a school of copepods, with opercula expanded so their red gills are visibleAnimation showing how herrings hunting in a synchronised way can capture the very alert and evasive copepodSailfish herd with their sails.Swordfish slash with their swords.Thresher shark strike with their tails.Spinner shark spin on their axis.A pair of humpback whales, a species of rorqual, lunge feedingGannets 'divebomb' at high speedLow densityHigh densityLow polarityHigh polarity Boids simulation – needs Java In biology, any group of fish that stay together for social reasons are shoaling (pronounced /ˈʃoʊlɪŋ/), and if the group is swimming in the same direction in a coordinated manner, they are schooling (pronounced /ˈskuːlɪŋ/). In common usage, the terms are sometimes used rather loosely. About one quarter of fish species shoal all their lives, and about one half shoal for part of their lives. Fish derive many benefits from shoaling behaviour including defence against predators (through better predator detection and by diluting the chance of individual capture), enhanced foraging success, and higher success in finding a mate. It is also likely that fish benefit from shoal membership through increased hydrodynamic efficiency.