how to identify wild fishes

Question
How a fish eating fish or a wild non friendly to other fish (oscar or betta  etc )look like? describe how to identify them from their physical features & behaviour.i know there are some but wanna know more.thanks.

Answer
Hello,
Good question.

Predatory fish typically have unique characteristics. Obviously something with a big mouth full of sharp teeth is probably a predator.

There are thousands of different predators, all displaying unique physical characteristics and behaviors. Many (such as the beta and oscar) are actually omnivores, meaning they eat both animal and plant based foods.

Since there are so many, I will tell you briefly about my favorites. I cannot send you pictures without violating some legal agreement, but you should be able to look them up online.
1.) Northern Pike- note the large eyes and powerful, streamlined body. This fish uses it's camouflage and acute senses to detect prey, and then it's extreme speed and power to catch and devour it's victim.

2.) Arowana- Similar to the pike, only capable of jumping up to 2 meters in the air to catch bugs/birds.

3.) Stingray- ambush predator. Hides burried in the sand until something (like a small fish or shrimp) comes into it's area, where it pounces on the prey and uses it's shark lake jaws to kill and eat the prey.

4.) Archerfish- Can spit a jet of water to accurately knock prey off of overhanging branches and into the water, where it is eaten.

5.) Trout- Highly active, feeds regularly whenever something small like a macroinvertibrate drifts by.

6.) Leaf Fish- it looks just like a leaf! It just sits and floats in the current until a small fish swims by, and is eaten. The small fish could not tell this was infact another fish because it looks so much like a harmless leaf.

All of these fish have very acute senses, most notably, the eyes. You can tell predator vs prey fish by looking at their eyes and moth. Predators typically have very small or very large eyes and a large mouth, whereas prey fish tend to have small mouths and medium-large eyes.


Colorful fish are often the most aggressive if for territorial rather than predatory purposes. There is really no other reliable way to identify them as a whole.