1. Fish with Lungs: The lungfish is a unique fish species that can breathe air. It has developed primitive lungs, allowing it to survive in oxygen-depleted waters by gulping air from the surface.
2. Electric Fish Communication: Some fish, like the electric knifefish, use electric signals to communicate with each other. They generate weak electric fields and can detect changes in these fields to locate prey and communicate.
3. Fish Farming Ducks: In parts of Southeast Asia, farmers use ducks to help with fish farming. The ducks paddle through the water and disturb the sediment, helping to control pests and increase fish food sources.
4. Fish “Walking”: The mudskipper, a type of fish, has adapted to survive in both water and on land. It has strong pectoral fins that allow it to “walk” on land and even climb trees to escape predators.
5. Fish with Teeth on Their Tongues: The parasitic fish called the “tongue-eating louse” enters a fish’s mouth, attaches to its tongue, and eventually replaces the tongue with its own body. It then feeds on the host fish’s blood and mucus.
6. Fish in Treetops: During seasonal flooding, the Amazon river basin experiences “flooded forests,” where fish like the arapaima swim through the treetops to find food in the temporarily submerged areas.
7. Fish with Built-In Flashlights: The flashlight fish has special light-producing organs under its eyes. It can flash these lights on and off to communicate with other members of its school and even confuse predators.
8. Fish Mating with “Dance”: The seahorse performs a mating dance that involves synchronized swimming, changing colors, and intricate movements. After the courtship dance, the male seahorse becomes pregnant and gives birth.
9. Fish with Blue Blood: Unlike humans, fish have blue blood due to a copper-based molecule called hemocyanin, which helps transport oxygen. This molecule gives their blood a bluish tint.
10. Fish Longevity: The Greenland shark holds the title for the longest-lived vertebrate, with some individuals estimated to live for over 400 years. Their slow metabolism and cold environment contribute to their impressive lifespan.

Nature is truly diverse and fascinating, and these odd but true fish facts showcase just a glimpse of the wonders found beneath the water’s surface.