Gary Bell/ Oceanwide / Black-spot Goatfish (Parupeneus signatus) and Goldlined Seabream (Rhabdosargus sarba) school, Solitary Islands Marine Park, New South Wales, Australia

Tony Wu / Twinspot snapper (Lutjanus bohar) shoal rushing up to spawn, releasing a cloud of milky white sperm and eggs in the water column. Caroline Islands, Palau, November.

Tony Wu / Twinspot snapper (Lutjanus bohar) engaged in a mass spawning aggregation early in the morning. Caroline Islands, Palau. April. Winner of Underwater category, Wildlife Photographer of the Year 2016.

Alex Mustard / Portrait of pair of Bohar snappers (Lutjanus bohar) in their spawning aggregation. Shark Reef, Ras Mohammed Marine Park, Sinai, Egypt. Red Sea.

Alex Mustard / Portrait of Bohar snappers (Lutjanus bohar) in its spawning aggregation. Shark Reef, Ras Mohammed Marine Park, Sinai, Egypt. Red Sea.

Franco Banfi / Diver with rebreather inside sea cage used for aquaculture with thousand of Gilt-head bream (Sparus aurata) Ponza Island, Italy, Tyrrhenian Sea, Mediterranean. Model released.

Franco Banfi / Diver with rebreather inside sea cage used for aquaculture with thousand of Gilt-head bream (Sparus aurata) Ponza Island, Italy, Tyrrhenian Sea, Mediterranean. Model released.

Franco Banfi / Thousand of Gilt-head bream (Sparus aurata) inside a sea cage used for aquaculture, Ponza Island, Italy, Tyrrhenian Sea, Mediterranean

Franco Banfi / Fish farm net of sea cage with thousands of Gilt-head bream (Sparus aurata) Ponza Island, Italy, Tyrrhenian Sea, Mediterranean

Wild Wonders of Europe / Banfi / Cow bream / Saupe (Sarpa salpa) Larvotto Marine Reserve, Monaco, Mediterranean Sea, July 2009

Gary Bell/ Oceanwide / Black-spot Goatfish (Parupeneus signatus) and Goldlined Seabream (Rhabdosargus sarba) school, Solitary Islands Marine Park, New South Wales, Australia

Gary Bell/ Oceanwide / Black-spot Goatfish (Parupeneus signatus) and Goldlined Seabream (Rhabdosargus sarba) school, Solitary Islands Marine Park, New South Wales, Australia