A female white whale and her calf are seen at the Chimelong Ocean Kingdom breeding centre in Zhuhai, Guangdong Province, China. Photo by Xinhua News Agency/Barcroft Images)





A spiral tube-worm in Neptune grass meadows in the Mediterranean Sea, near Marseille, France. Recreational boats seriously damage the ecosystem by plowing the seabed with their anchors. Neptune grass, or Posidonia oceanica, a protected species, grows only a few centimetres a year and blooms only a few times a decade, but does a lot of work. The mat that it forms offers shelter to small fish, traps carbon and produces oxygen, and its leaves limit erosion caused by waves. (Photo by Boris Horvat/AFP Photo)





Getting up close to a sperm whale. This one is part of the pod that Blue Planet filmed off Sri Lanka, where tourism is making the coast less safe. (Photo by Andrew Sutton/The Guardian)





In this September 10, 2018, file photo a lobster takes a defensive posture as it moves to hide below aquatic plants off the coast of Biddeford, Maine. Trade hostility from across the ocean was supposed to take a snip out of the U.S. lobster business, but the industry is getting a help from Canada with its heavy demand for American lobster. It's a positive sign for the U.S. as the seafood industry struggles with Chinese tariffs. (Photo by Robert F. Bukaty/AP Photo)





A shark said to be “Deep Blue”, one of the largest ever recorded great white sharks, swims off the coast of Hawaii, January 15, 2018. (Photo by @JuanSharks/@OceanRamsey/Juan Oliphant/oneoceandiving.com via Reuters)





A star basket (Gorgonocephalus chilensis) in the Beagle Channel, Chile. It is not a starfish, since it belongs to the class Ophiuroidea. It lives on high points in areas exposed to currents, where it extends its arms to capture food. (Photo by Felix JL Zampelunghe/Secretos del Mar/Greenpeace)





Underwater image captured by the Remus SharkCam autonomous vehicle observing the behaviour of basking sharks off the west coast of Scotland. (Photo by Amy Kukulya/@oceanrobotcam via Reuters)





Young fish swim around a new 3D printed artificial reef, off the city of Le Cap d'Agde, southern France, on July 10, 2019. Around thirty 3D printed artificial reefs have been sunk ten kilometres off the coast, aimimg to preserve and develop biodiversity. (Photo by Boris Horvat/AFP Photo)





A picture taken on April 7, 2019 shows a basket star, or Gorgonocephalidae Astrospartus, near La Ciotat, southern France. (Photo by Boris Horvat/AFP Photo)





A squid swims underwater off the shore of the coastal city of Qalamun, north of the Lebanese capital Beirut, on September 24, 2019. (Photo by Ibrahim Chalhoub/AFP Photo)





This underwater picture taken on July 29, 2019, shows a jelly fish near a spearfishing practitioner off the coast of the northern Lebanese town of Qalamun, on the outskirts of north Lebanon's capital, Tripoli. (Photo by Ibrahim Chalhoub/AFP Photo)





An underwater photo shows a 14 meters long submerged ship with copper ingots in it belonging 1600s BC in Antalya, Turkey on April 5, 2019. (Photo by Tahsin Ceylan/Anadolu Agency/Getty Images)





Australian giant cuttlefish mating during the annual mating and migration season, in Point Lowly, South Australia, last June. Once a year in freezing cold winter waters, a gathering happens off the coast. Hundreds of thousands of giant cuttlefish come to mate but this natural wonder comes at a great cost. In this episode of Guardian Australia’s new podcast, we learn a lesson on life and death from these amazing cephalopods. (Photo by Wildestanimal/Alamy Stock Photo)





French oyster aquaculturist Jean-Christophe Cabrol checks the growth of oysters covered with sea squirts (“BIJU” in French) on collector lines in a shellfish farming in the pond of Thau in Bouzigues, near Montpellier. (Photo by Boris Horvat/AFP Photo)





Wedgefish off Heron Island, Australia. Giant guitarfishes and wedgefishes are shark-like rays and their “fins” are some of the most valuable in the shark fin trade. They have recently been reclassified as critically endangered by the IUCN and are now the most endangered marine fish in the world. (Photo by Danny Copeland/Humane Society International UK)





Baby California sea lions (Zalophus californianus) swimming in a kelp forest off the Channel Islands, California. (Photo by Antonio Busiello/Alamy Stock Photo)





A Southern Right Whale (Eubalaena australis) is seen at Ribanceira Beach, Imbituba, Santa Catarina state, Brazil on July 09, 2019. The Southern Right Whale is coming from Antartica in this time of the year. (Photo by Eduardo Valente/AFP Photo)





This undated photo made available by The Pew Charitable Trusts shows the giant guitarfish. Countries have agreed to protect more than a dozen shark species at risk of extinction, in a move aimed at conserving some of the ocean’s most awe-inspiring creatures who have themselves become prey to commercial fishing and the Chinese appetite for shark fin soup. Three proposals covering the international trade of 18 types of mako sharks, wedgefishes and guitarfishes each passed with a needed two-thirds majority in a committee of the World Wildlife Conference known as CITES on Sunday Aug. 25, 2019. (Photo by Danny Copeland/The Pew Charitable Trusts via AP Photo)





Kristina Zvaritch, a freediver, swims above manta rays up to 6m (20ft) long off Komodo island, Indonesia. (Photo by Yahia Barakah/Mercury Press)





A whale bursts from the waves directly behind a fisherman's boat at Monterey Bay, California in 2019. (Photo by Douglas Croft/Caters News Agency)





Hundreds of human-sized jellyfish have been spotted lurking around the Cornish coast in the past few days, in the middle of July 2019. Marine experts have said that there have been more sightings of these gigantic creatures this week than in the last 15 years. Barrel jellyfish are the largest species of jellyfish found in British waters, with a diameter of up to 90cm and weights of up to 35 kilos. (Photo by South West News Service)





An 8 metre whale sharks swims under a tourist boat in the Ningaloo Reef, off the coast of Western Australia. (Photo by Ocean Collective Media/South West News Service)