Defense Mechanisms of Ocean Fish
How Fish Avoid Predators in the Sea
The ocean can be a dangerous place for a small fish. Fortunately, nature has bestowed a number of defense mechanisms on the ocean’s fish, helping them to escape predators. From camouflage to poisons to flying, fish have a number of ways to find safety.
Why are Fish Light on the Bottom and Dark on Top?
Many fish use a coloration scheme called ‘countershading’ to hide from predators. These fish have light colored undersides and dark tops. As the National Aquarium in Baltimore notes in its online article “Fish Biology and Anatomy” many of these fish live in the open ocean. Seen from above these open ocean fish blend in with the dark depths below. Seen from below they blend in with the light filled waters and sky above. This is one useful defense mechanism fish use to avoid predators.
Fish Avoid Predators with Camouflage
It may come as a surprise but those brightly colored coral reef fish are actually using camouflage to hide from and confuse predators. The bright colors of these fish help them blend in with the colorful corals around them. As the National Aquarium in Baltimore goes on to say, many fish use a defense technique called ‘disruptive coloration’ where patterns or lines help these fish blend in with their background. Fish such as the rockfish and frogfish are masters of camouflage, blending into rocks, corals, and plants. However these fish use camouflage to hide from prey, waiting to strike until prey are near. Also, many sea creatures including fish can change color for camouflage.
Fish Avoid Predators with Fake Eyespots
Fish have another defense mechanism involving color called mimicry. A fake eyespot near the tail can confuse predators by drawing attention from the real eye says the National Aquarium in Baltimore. As the confused predator goes after the fake eyespot the preyed upon fish can swim away and escape.
Why Do Fish Travel in Schools?
There are a number of reasons fish travel in schools and one is for safety from predators. As Prentice Stout notes in the Rhode Island Sea Grant Fact Sheet “Fish Schooling” roughly 80% of known fish use schools. One reason schooling is believed to work is because predators usually hunt for creatures smaller then they are. A school of small fish gives the illusion of a larger fish. The schooling fish are also playing their odds of not getting eaten as a predator cannot eat an endless amount of food. Fish in the center of the school are safer than those on the edges.
Fish That Fly Away From Predators
The flying fish can glide for 200 meters (655 feet) over the water reaching a height of 1.2 meters (4 feet) to escape from predators as the National Geographic notes in its online “Flying Fish” profile. The flying fish has many predators including tuna, mackerel, and swordfish from which it flies away from. The flying fish rapidly beats its tail fin to launch out of the water and then spreads its pectoral fins to glide through the air.
Spines and Poison Deter Fish Predators
Some fish are more aggressive with their defense against predators. Rather than run or hide these fish protect themselves with spines or poison. The pufferfish, known for inflating itself against predators also often has spines. It is also contains a nasty tasting poison lethal to fish and humans reports the National Geographic it its ‘Pufferfish Profile’. Other poisonous fish include the lionfish and the stonefish. The South Caroline Aquarium notes in its profile for the “Ocean Surgeonfish (Acanthurus bahainus)” that the surgeonfish has a sharp spine at the base of its tail that can do harsh damage to a would be predator.
Defense Mechanisms Against Predators
Although not an exhaustive list camouflage, traveling in schools, spines, poisons, and speed are all useful defense mechanisms under the sea. Fish are not the only prey in the ocean of course and other sea creatures have developed their own defense mechanisms against predators.
Butterfly Fish Avoids Predators With Eyespot
|
Fish Travel in Schools to Escape Predators
|
The Pufferfish Has Several Defense Mechanisms
|
What do you think about this article?
More in Science & Nature
Latest Articles