Bats

• Most species of bats feed on insects. Larger bats, such as vesper bats, are known to prey on small fish as well. There are more than 40 genera of vesper bats, and they are the second-largest family of mammals. The vesper bats that have evolved to prey upon fish have developed sharp claws for pulling minnows out of the water, according to Desert Museum. These bats are called fish-eating bats, and they are found only along the coasts of California. Fish-eating bats are of the most endangered species in the world. They live in the rock rubble and talus slopes of California's remote coastal areas and fish in shallow, calm sea water.
  
  

Catfish

• Catfish, as their name suggests, are a nocturnal, predatory fish. They are piscivores, meaning that they eat fish exclusively. Hunting at night, catfish track the wakes left by their prey. According to the Journal of Experimental Biology, hydrodynamic and chemical signatures in the wake give the catfish information about the fish they are tracking. Their diet includes almost anything they come across, including dead fish, live fish, insects, worms, clams and even small rodents. There are species of catfish in both salt and fresh waters. The largest known catfish is a Wels catfish, which has been known to grow to 16.5 feet.
  
  

Moray Eels

• Moray eels can be many colors from brown or yellow to brightly spotted and striped.Jupiterimages/Photos.com/Getty Images
  
  Moray eels are tropical coral reef dwellers. They can grow to lengths of 12 feet. Moray eels eat fish, cephalopods, mollusks and crustaceans. They hunt at night, and because of poor eyesight, moray eels rely heavily on their sense of smell for hunting. Weakened or dead creatures are of particular vulnerability to eels. Their keen sense of smell leads them right to the animal. When hunting healthy prey, moray eels hide in coral crevices and wait for fish to swim by. When they see a fish, they strike out at a very fast speed and catch the fish with powerful jaws. Very large moray eels have even been known to prey upon smaller moray eels.
  
  

Night Heron

• The black-crowned night heron looks slightly different than most herons.Jupiterimages/Photos.com/Getty Images
  
  Night herons can be found on every continent except for Australia and Antarctica, according to the Smithsonian National Zoological Park. The black-crowned night heron is among the most common heron species in the northern United States. Herons primary food is fish, but they also eat eggs, small birds and mammals, crabs, mollusks and amphibians. They hunt at night and early in the morning. They stand still in waters waiting for fish to swim beneath them. When the fish appear, they lunge forward with a powerful neck thrust. The fish is speared on the end of the night heron's sharp beak.