Jellyfish are 98% water, contain no brain, and only possess a very basic nervous system to help them detect changes in the water. But they are some of the oldest animals on earth, with fossils dating back 500 million years (predating dinosaurs). Typically, when we see jellyfish, they are moving in groups. But what is a group of jellyfish called, and how do they behave within one? Let’s find out!
What is a Jellyfish Group Called?
A group of jellyfish is called a swarm or a bloom. But you can also call them a smack, fluther, brood, smuth, shoals, or stuck. Many think the most common collective noun for jellyfish is a smack. But most scientific literature uses the terms “Swarm” and “bloom” when discussing these animals.
However, a smack of jellyfish does sound pretty cool.
A normal group of jellyfish is called a swarm. If there is a sudden increase in their numbers in one specific area, you would call this a bloom. A bloom typically occurs when there is an increase in food, like plankton. They will form a sudden grouping in the area to feed.
Why is a Group of Jellyfish Called a Smack?
The term “smack of jellyfish” was invented as an informal name to describe the characteristics of this animal. Jellyfish are called a smack because that’s what it feels like when they sting you. They can also cause swelling and red skin, similar to what getting smacked on your hand or face may look like. But a smack typically describes minor jellyfish stings. Some jellyfish stings can cause systemic illness and become life-threatening, such as a box jellyfish sting.
The general term “swarm” describes their behavior in the water as they swim together in the same area. And “bloom” describes a large group but also refers to their movements.
How Do Jellyfish Behave in Groups?
Jellyfish do not have social behavior. And their groupings are primarily due to converging water currents. These creatures don’t have brains. Instead, they rely on basic nerves and automatic reflexes, even feeding is left up to chance. However, there are some theories that certain species, like the helmet jellyfish, may gravitate towards others in its species to increase their hunting chances.
For the most part, jellyfish only group together when they are moving in the same direction or following the same food source. And until further research proves otherwise, these swarms are most likely coincidental.
Are Jellyfish Social or Solitary?
Jellyfish are typically considered loners, especially larger species. But smaller jellyfish may stick together to decrease their risk of predation. While you may find jellyfish in dense swarms, they are not your average social animal that lives in groups. These creatures don’t socialize and only swarm together when they are following the same path or food source.
Here are some of the most frequently asked questions for “what is a group of jellyfish called?”
What is a Group of 100 Jellyfish Called?
“Swarm” is the most common collective noun for groups of jellyfish. And “bloom” describes a sudden increase in the number of jellyfish. The specific amount does not matter.
What is a Group of Man O War Jellyfish Called?
The man o’ war is actually not a jellyfish. They are siphonophores, marine animals that consist of a colony of individual parts called zooids. Zooids can’t function on their own, so they stay connected and grow into different forms. A group of zooids or man o’ wars is called a colony.
What is a Group of Box Jellyfish Called?
Like all jellyfish, the box jellyfish is called a swarm, bloom, or smack. This species, however, is rather advanced compared to other jellyfish. They can move rather than drift. And they have clusters of eyes on their bells. The box jellyfish is the most dangerous marine animal on earth, causing paralysis, cardiac arrest, and even death within mere minutes of being stung.
The photo featured at the top of this post is © mishelo0/Shutterstock.com
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