“Large schools of fish can also confuse an attacker by making it WorldMags.net ENVIRONMENT difficult for it to single out its prey”
Shoaling versus schooling Discover how and why fish stick together as they travel the oceans A group of hundreds or sometimes thousands of fish swimming in unison is one of the most spectacular sights in nature, but what is the reason for this incredible phenomenon? First, it is important to understand the subtle difference between shoaling and schooling. A shoal is a social group of fish swimming closely together but foraging for food individually. Those shoals can consist of different species and sizes of fish. A school of fish swim in a more synchronized fashion, moving at the same speed and turning simultaneously. These groups often consist of a single species. Some species, including tuna and herrings, are obligate shoalers, meaning they spend all of their time either shoaling or schooling. Others, such as Atlantic cod, will only shoal some of the time, often when they are looking for a mate. In addition to reproduction, there are several other reasons why fish congregate in shoals or schools. One is that it gives them the advantage of safety in numbers, as being part of a group reduces the chance of a fish being eaten by a predator. Large schools of fish can also confuse an attacker by making it difficult for it to single out its prey or even scare the predator off by resembling one large fish. Another benefit is that several eyes are better than one, and so a shoal of fish is much quicker at spotting food or a potential predator than one fish is on its own. Scientists also believe that swimming in unison gives the fish more hydrodynamic efficiency, as the beating of the front fish’s tail helps to propel those in its wake.
076 | How It Works
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