A Hawaiian cleaner wrasse provides its cleaning services to a yellowfin goatfish in a reef community off the Big Island in Hawaii. Cleaner species help rid their hosts of ectoparasites, dead tissue, bacteria and fungi. Studies have shown cleaning to play a vital role in keeping many reef ecosystems healthy. (Photo by Marty Snyderman/Caters News Agency)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)

One of three young oriental small-clawed otters eats a meatball on June 18, 2015 in a zoo in Dresden, eastern Germany. The oriental small-clawed otter female Fussi gave birth to 3 healthy pups. Its pups now leave their burrow to explore the environment. (Photo by Arno Burgi/AFP Photo/DPA)

Polar frame, by Dmitry Kokh, Russia. When Kokh’s boat approached the small island of Kolyuchin in the Russian High Arctic, which had been abandoned by humans since 1992, he was surprised to spot movement in one of the houses. Binoculars revealed polar bears – more than 20 in total – exploring the ghost town. Dmitry used a low-noise drone to document them. (Photo by Dmitry Kokh/Wildlife Photographer of the Year 2022)

A caiman swims amidst trash in Canal das Taxas at the Recreio dos Bandeirantes neighborhood in west Rio de Janeiro, Brazil, on November 22, 2023. The urban expansion of the area and the resulting pollution have put the yacare caiman (Caiman latirostris) “in danger of extinction”. (Photo by Tercio Teixeira/AFP Photo)

A woman walks past a stall at a market in Banjul, Gambia December 15, 2016. (Photo by Afolabi Sotunde/Reuters)

A woman arranges peppers for drying in the sun as seasonal workers process tomatoes after a harvest in Gaziantep, Turkey on August 10, 2021. Drying of peppers, zucchinis, eggplants and gherkins began. (Photo by Mehmet Akif Parlak/Anadolu Agency via Getty Images)

Competitors Taisto Miettinen and Katja Kovanen fron Finland participate in the annual Wife Carrying World Championships in Sonkajarvi, Finland on July 6, 2019. People from all over the world took part in the event that was founded in 1992. (Photo by Mauri Ratilaine/EPA/EFE/Rex Features/Shutterstock)