Threats of the White Perch
White Perch can quickly become dominant species in freshwater lakes. By preying on young fish, eggs, native species, and others, they can soon tilt the food chain which gives them a clear advantage. Another fallback is that White Perch are able to spawn in brackish and freshwater, which means that they always have a second means of survival if managed to drive them out of one place. Also, this species could spread further inland in the United States, and has already invaded the Ohio River. According to Indiana Department of Natural Resources, the White Perch has dominated the fishery 88% by number 67% by weight in Cedar Lk. Already of clear nuisance in states of the Midwest, these states need a plan of action to control this species - fast.
Harmful DietWhite Perch are omnivores, meaning they can consume food of animal and plant origins. However, mainly feeding on meat, this species has a long list of prey, specifically fish eggs, which is why it is able to eliminate so many native species of Lake Michigan. They also feed on an excessive amount of minnows, including the fathead and mudminnows, and in doing so, they are out-competing many foragers, which in turn affects predators on a larger scale. They also eat zooplankton, which are microscopic organisms responsible for maintaining algae. Cutting their population down means increasing chances for algal blooms, which causes a significant amount of damage to all organisms living in the area. Aquatic plants would no longer be able to photosynthesize, temperatures plummet, sunlight cannot enter, oxygen levels decrease, and overall, many native fish are left unable to survive.
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InterbreedingAccording to fishing reports from Kansas, Iowa, Indiana, Illinois, and other states, the White Perch has managed to interbreed with the known White Bass, Morone chrysops, a native to the great lakes, and can dilute both gene pools, creating a new unwanted hybrid.
White Bass (top) is capable of interbreeding with the White Perch (bottom), which degrades the breeding pool in the Great Lakes.
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