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Animals That Eat Freshwater Fish

Freshwater fish are found throughout lakes and streams, and they make up an important staple of the diet of many types of animals. Not only are fish prey to animals such as birds and bears, smaller freshwater fish comprise the diet of larger fish such as bass. Furthermore, humans often rely on fish as a healthy food source and have changed their natural habitat to raise them on farms, often increasing the toxin levels in the fish.

Bears
- Grizzly bears consume fish when they are available prior to their hibernation.
  
  Though bears hibernate in the winter, they do not go into a true hibernation but rather an extremely deep sleep, meaning that though their metabolism slows down, they still need a large amount of calories for their daily survival. Because of this, bears must stock up their calories during the rest of the year. Grizzly bears are not adapted to eating plants; they cannot digest cellulose. They rely primarily on a meat-based diet, including freshwater fish. Though grizzly bears located on the eastern slope of the Rocky Mountains have limited access to fish, others located westward consume trout and salmon as an important staple of their diet. Black bears are omnivores, meaning they eat a wide range of foods. However, meat is their preferred source of food, and they eat freshwater fish such as bass whenever it is available.
Fish
- Trout will consume smaller fish.
  
  While trout themselves are often the prey for other animals, they also eat smaller freshwater fish. Lake trout consume rainbow smelt and other small fish, as well as insects and crustaceans. Salmon's diet consists of krill, which gives salmon their pink color. However, farm-raised salmon do not eat krill and are therefore dyed a pinkish color to provide a product consumers expect.
Birds
- Pelicans swallow freshwater fish whole.
  
  Various bird species also rely on freshwater fish for their diet. Pelicans hunt both oceanic and freshwater fish, and they catch them in the large portion of their throat called the throat pouch. They scoop up the fish and store them in the pouch. Then they drain the water and swallow the fish whole. Pelicans often hunt for fish in groups, moving schools of fish toward shallow parts of the water and then scooping them up. Various species of eagles often consume freshwater fish. There are 59 species of eagles, each with varied diets; the bald eagle, in particular, is known for hunting freshwater fish through grasping the fish with their talons from rivers and lakes.
Humans
- Humans consume salmon after grilling, poaching, baking or smoking.
  
  Humans also consume freshwater fish such as salmon, trout and bass. While wild-caught fish are often available to consumers, most of the fish that appear at markets are farm-raised. Said Jane Houlihan, senior vice president for research of the Environmental Working Group, in a cnn.com article, "Nearly all salmon Americans eat are farm-raised." The problem with farm-raised fish is that they are often raised in environments with many toxins, due to the high level of excrement in the water. If wild-caught fish is not available, Dr. Melina Jampolis, a nutrition specialist, recommended on cnn.com to purchase farm-raised salmon exported from Canada, as the toxin levels for Canadian salmon tend to be lower. Many people consume fish for its high level of protein and healthy omega-3 fatty acids. Popular ways of preparing freshwater fish include grilling, baking and smoking, and fish are often served with lemon, butter, Cajun seasoning or salsa. People also consume fish as sushi and sashimi.

Animals & Science