Let's go back to our roots and talk about freshwater fish you can probably catch. In the deep waters of Eastern Europe and Western Asia lives the largest-bodied European freshwater fish, the Wels catfish also known as sheatfish. The Wels catfish can grow up to 3 meters (9ft 11in) and weigh up to 150 kilograms (330lbs). Though the fish is considered a trophy to some anglers it is also an extremely invasive species having a mean risk score of 21.5 out of a possible 54. which means that it can inhabit different habitat types and will consume a wide range of food items within its environment. And with the female Wels catfish laying up to 700,000 eggs at a time and the male strongly guarding the eggs, an invasion can easily happen where these impacts could easily be felt.