From a friends garmim on texoma. Are these fish? This was 60' deep and the marks are at 45'. It's an old garmin unit that came with the boat that he just purchased.
The only way to know for sure is to lower the lure at 45 ft and wait for the strong "crappie thump" and do ninja sethook. On most modern graphs that is shad.
We weren't fishing. My friend recently got the boat and we were trying it out. I don't know garmins at all so I don't know what fish look like on them. It is an old unit with software from 2014. We came on those marks on the screen and I didn't know what they were. Several guys were fishing in that area so I thought it might be fish.