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)

An aircraft drops water during a wildfire near Olympia town, western Greece, Thursday, August 5, 2021. Wildfires rekindled outside Athens and forced more evacuations around southern Greece Thursday as weather conditions worsened and firefighters in a round-the-clock battle stopped the flames just outside the birthplace of the ancient Olympics. (Photo by Giannis Spyrounis/ilialive.gr via AP Photo)

A Bangladeshi man carries a duck as he returns to Dhaka after Eid-al-Fitr celebrations, at the Sadarghat launch terminal in Dhaka, Bangladesh, 28 April 2023. Muslims around the world celebrate Eid al-Fitr, the three-day festival at the end of the Muslim holy fasting month of Ramadan. Eid al-Fitr is one of the two major holidays in Islam. (Photo by Monirul Alam/EPA)

Turkish World Record Holder in freediving Sahika Ercumen dives to raise awareness about pollution in sea waters in Kas district of Antalya, Turkiye on June 07, 2023. Every year 400 tons of one time use plastic are made globally and in Turkiye 91 percent of the plastics are not recycled. (Photo by Sebnem Coskun/Anadolu Agency via Getty Images)

Seattle Mariners center fielder Julio Rodríguez laughs as teammate Teoscar Hernández douses him as they celebrate a 9-2 win over the Baltimore Orioles in a baseball game Friday, August 11, 2023, in Seattle. (Photo by Lindsey Wasson/AP Photo)

Members of the Pentacle Drummers perform in front of a burning wicker man during the Beltain Celtic Fire Festival at Butser Ancient Farm, in Waterlooville, Hampshire on Saturday, April 29, 2023. (Photo by Andrew Matthews/PA Images via Getty Images)

This photograph taken during a government organised media tour shows people in traditional costume standing in Potala Palace Square as the Potala Palace – classified as a World Heritage Site by Unesco in 1994 – is seen in the background in the regional capital Lhasa, in China's Tibet Autonomous Region, on June 1, 2021. (Photo by Hector Retamal/AFP Photo)

A man carries a woman across a river at Petit Goave where a bridge collapsed during the rains of the Hurricane Matthew, southwest of Port-au-Prince, October 5, 2016. (Photo by Hector Retamal/AFP Photo)