Large schools of fish on side scan sonar
 

These images I took while scanning Moultonboro Bay, roughly between Garnet Point and Elkins Pt..

Depths ranged from 50 feet to 106 feet. Width of the total scan left to right was about 330 feet (50 meters per side). 106 was not a common depth though.

I saw dozens of these schools. Many were between 40 feet and a little more than 60 feet in length. I assume they were bait fish of sorts as opposed to say trout, bass etc.. I estimate they were about 4"-7" in size, whatever they were.

The schools are the clouds of small yellow dots in the black area in the center of the screen, what is known in sonar as the Nadir region.

I think 7" is a bit large but I believe the primary "baitfish" in all of our salmon/trout managed lakes is the rainbow smelt.
Usually, fishermen refer to these clouds of baitfish as smelt.

I need a better fish finder.

Lol...I have that side scan feature on my Garmin but I don’t use it as I never knew what the hell I was looking at.