underwater elegance: vast shoal of mackerel scad in sunlit ocean depths

underwater shoal mackerel scad ocean fish sea life black white sunlight marine wildlife aquatic nature natural swarm school deep scuba diving fishing environment ecosystem world silhouette oceanography biological sustainable monochrome watery depths biology conservation zoology animals water habitat creatures submarine exploration subaquatic light rays oceanic fisheries elegance: vast sunlit dramatic capturing large decapterus macarellus swimming dynamically illuminated filtering