Like people, some fish would rather live alone while others prefer company. For those that group together, they are termed shoaling fish or schooling fish.
Shoaling fish are an unorganised group where individual fish may not swim facing the same direction. Examples of shoaling fish are anchovies and herring.
Schooling fish are groups that swim together in the same direction, and in a coordinated manner. Examples of schooling fish are surgeonfish and rabbitfish.
But what are the reasons behind such “pack behavior”? Is it simply a matter of safety in numbers? We fished out some interesting information from our experts.
Stay close, stay safe
Schooling or shoaling makes perfect sense especially if you’re on the menu of larger fish.
Fish in a shoal have a lower probability of being targeted by a predator compared to fish on their own. Shoals may also be mistaken for a large fish and therefore be avoided by an approaching predator.
Seek together, eat together
Shoals and schools have higher chances of success when hunting for food. They tend to locate food sooner, ingest faster and have more time for foraging instead of looking for threats.
Love and babies
There’s strength in numbers, and there’s love too. Shoals or schools provide increased access to potential mates. Much like speed dating as you swim. Because of that, they also tend to result in synchronised reproductive behaviour, leading to multiple conceptions and consequently births in a restricted time period. That’s what we call a baby boom.
Do you know that by swimming together, the increased hydrodynamics actually allow the fish to save energy? In fact, they can save 65% energy by swimming in an area of reduced flow created by the fish in front of them. So what do they do with all the extra energy? They feed and reproduce.
Just as families have house rules, so do schooling fish. Here are the “Three Commandments of Schooling”:
- Thou shall move in the same direction as thy neighbours
- Thou shall remain close to thy neighbours
- Thou shall avoid collisions with thy neighbours
Learn even more fascinating facts about schooling fish at the S.E.A. Aquarium this festive season. Here’s a rundown of what you can expect at Merry Fishmas.