Jordi Chias / European barracuda (Sphyraena sphyraena) and Bluefish (Pomatomus saltatrix) circling baitball of Atlantic horse mackerel (Trachurus trachurus) Formigas Islets, Azores. Finalist in the Underwater Categ...

Norbert Wu / Garibaldi (Hypsypops rubicundus) and Pacific Jack Mackerel (Trachurus symmetricus) school in Giant Kelp (Macrocystis pyrifera) forest, Catalina Island, California

Norbert Wu / Garibaldi (Hypsypops rubicundus) and Pacific Jack Mackerel (Trachurus symmetricus) school in Giant Kelp (Macrocystis pyrifera) forest, Catalina Island, California

Aflo / Northern sea nettle (Chrysaora Melanaster) floating, with Mackerel fry ( Carangidae) Izu, Japan. January.

Sue Daly / Koheru (Decapterus koheru) shoal swiming around diver, Cavalli Islands, New Zealand, February 2013. Model released.

Todd Mintz / Bar Jack (Caranx ruber) predating a dense school of Scad fish / Horse mackerel (Trachurus trachurus) Bonaire, Dutch Caribbean.

Todd Mintz / Bar Jack (Caranx ruber) predating dense school of Scad fish / Horse mackerel (Trachurus trachurus) Bonaire, Dutch Caribbean.

Jordi Chias / Atlantic spotted dolphins (Stenella frontalis) chasing fish (Trachurus trachurus) Santa Maria Island, Azores, Portugal, Atlantic Ocean

Norbert Wu / Garibaldi (Hypsypops rubicundus) and Pacific Jack Mackerel (Trachurus symmetricus) school in Giant Kelp (Macrocystis pyrifera) forest, Catalina Island, California

Norbert Wu / Pacific Jack Mackerel (Trachurus symmetricus) school in Giant Kelp (Macrocystis pyrifera) forest, Catalina Island, California

Franco Banfi / Blue jack mackerel, (Trachurus picturatus) baitball, Formigas Islet dive site, Azores, Portugal, Atlantic Ocean

Pascal Kobeh / Yellowtail surgeonfish (Prionurus punctatus) grazing algae with a school of jack mackerels (Trachurus symmetricus) Baja California peninsula, Mexico. Sea of Cortez.