To identify if a fish shown on front-facing sonar is a bass, there are a few key factors to consider. First, look for arches on the sonar display. Arches indicate the frequency of the sonar ping bouncing off the back of the fish, which is a clear readout of a fish. Sometimes, the arches may be sideways or incomplete, but they still indicate the presence of fish. In the video, the angler mentions that the arches represent fish, including bass.
Additionally, you can use other features on the sonar display to confirm if the fish are bass. Look for the fish's air bladders on the down imaging and schools of fish on the side imaging. The angler in the video mentions that the air bladders of the fish can be seen on the down imaging, and the schools of fish on the side imaging are not bass, but rather whites and yellow bass. The bass, whether largemouth, spotted, or smallmouth, are shown on the bottom of the display.
It's important to note that identifying fish species on a sonar display can be challenging and requires experience and practice. The angler in the video mentions that determining the species of fish using sonar images takes nuanced study and experience. However, for bass specifically, the angler provides a basic guideline. He suggests that bass on the sonar display will appear as dots about the size of a ballpoint pen tip.
Remember, the information provided is based on the video context and the angler's expertise. If you have any specific questions or need further clarification, please let me know.