When angling for freshwater species, it is not uncommon to catch a species of fish that you were not intending to catch. Many of us, rather than studying the creature and identifying it, will simply call it a “junk fish” and release it back into the water without giving the matter any further thought. Other people will try to identify the species, and this can be tricky when you’re out on the water and away from reference guides and encyclopedias. Here are a few species of freshwater fish that can be easy to misidentify, and how to differentiate between lookalike species.
1. Yellow Perch (often confused with the Smallmouth Bass). These two species often share the same waters and can be caught using the same lures. At first glance, they look similar in may ways; they are often similar in color and both have vertical bands of a darker color. The quickest and easiest way to tell whether you have caught a perch or a smallmouth bass is by looking at the eyes. A smallmouth bass will have red eyes, while perch have yellow or yellow-green eyes.
2. Sauger (often confused with the Walleye). Both fish are members of the Percidae family, and these fish are so closely related that they sometimes breed, creating a hybrid known as the “saugeye”. Saugers can be identified by their fins. Saugers have spotted dorsal fins, walleyes do not. Walleyes, on the other hand, have a white splotch on their tail fins, while saugers do not.
3. Northern Pike (often confused with the Muskellunge). Pike, muskellunge, and pickerels are all members of the Esox genus. Unlike a muskellunge, the northern pike has light markings on a dark body, while the muskellunge has dark markings.
4. Brown Trout (often confused with the Rainbow Trout). Since native trout are more colorful than stocked trout, it is sometimes difficult to identify stocked trout because they are not as brightly colored. This is especially true with brown trout and rainbow trout. Unlike the brook trout, which is easily identified by white streaks on their fins, a stocked brown trout can easily look like a stocked rainbow trout. An easy way to identify the two is by their coloration. Unlike brown trout, the rainbow trout has a pinkish or reddish horizontal streak of color running the length of its body.
These four species are common freshwater game fish that can easily be mistaken for other species of the same family. Also confusing matters is that many of these species can interbreed, resulting in hybrid species, like the saugeye, tiger trout, and the tiger muskellunge.