Mackerel scad are schooling fish, the kind that make ‘bait balls’ which end up being decimated by large predators. They’re members of the jack family, not that this does them much good. Some of those large predators are other members of the jack family such as greater amberjacks and almaco jacks.
I came across this school not far from shore. There were probably two or three hundred fish in the school and it was fun watching them twirl and circle in harmony. They encircled me, went past and I popped out the other side. It was then I noticed they weren’t alone. One the other side of the school, a medium-sized great barracuda cruised around.
The barracuda came toward me to take a look, but I was clearly less interesting than the scad and it moved away again. The barracuda can be seen in the bottom photo. See if you can spot it.