Behaviour: Mammals category. Giant Gathering by Tony Wu, USA. Dozens of sperm whales mingled noisily off Sri Lanka’s northeast coast, stacked as far down as Tony could see. This was a congregation of dozens of social units, like a gathering of the clans. Aggregations like this could be a critical part of the whales’ rich social lives but are rarely reported. Some two thirds of the population was wiped out before commercial whaling was banned in 1986. This kind of major gathering could be “a sign that populations are recovering”, says Tony. (Photo by Tony Wu/Wildlife Photographer of the Year 2017)

A woman walks protecting herself from rain after Hurricane Matthew in Les Anglais, Haiti, October 13, 2016. (Photo by Andres Martinez Casares/Reuters)

Two brown bears bathe in their enclosure at the Wildpark Poing in Poing, Germany, Wednesday, August 8, 2018. (Photo by Lino Mirgeler/Deutsche Presse-Agentur via AP Photo)

Rick Sorenson, owner of the Rio Ramaza Marina, wades in the Sacramento River after securing an old paddlewheel boat on his property as the river makes its way up the levee on Garden Highway in Sacramento, Calif., Monday, January 9, 2017. (Photo by Hector Amezcua/The Sacramento Bee via AP Photo)

People search for shells on a beach in Sittwe, Rakhine State, Myanmar, 17 September 2020. International Coastal Cleanup Day is observed annually on the third Saturday of September and will occur on 19 September this year. (Photo by Nyunt Win/EPA/EFE/Rex Features/Shutterstock)

A robot used to assist Covid-19 patients is seen in an elevator on December 5, 2020 in New Delhi, India. The “Mitra” robot can connect patients with their loved ones, and can assist healthcare workers on the frontlines of the pandemic by minimisng the risk of infections caused by close contact. The Yatharth Hospital, which is treating Covid-19 patients in Noida, on the outskirts of New Delhi, is one of a handful of hospitals in India that has started to use robots. (Photo by Anindito Mukherjee/Getty Images)

Sümi women gesture as they line up to perform a traditional Sümi rice pounding folk song called “Thishole” during Western Sumi Torimi Hoho Silver Jubilee at Thilixü Village in Chumoukedima district, India north eastern state of Nagaland on June 7, 2023. Altogether 1400 Sülimis perform their traditional rice pounding folk song to mark their 25th Anniversary. (Photo by Caisii Mao/Rex Features/Shutterstock)

Visitors enjoy a camel ride at Sea View beach in Karachi on June 16, 2023, after Cyclone Biparjoy made landfall. More than 180,000 people in the Indian state of Gujarat and Pakistan's neighbouring Sindh province fled the path of Biparjoy – which means “disaster” in Bengali – before it made landfall on June 15 evening. (Photo by Asif Hassan/AFP Photo)