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 frozen public bench is seen next to a lake side due to the heavy wind conditions in Geneva February 8, 2015. (Photo by Pierre Albouy/Reuters)

A gilrl plays games in a shopping mall in Beijing, China, 24 November 2021. Demographers in China have called for more efficient implementation of supportive measures to encourage births to address the country's dwindling population growth as country's birthrate last year was 8.52 births per thousand people, the lowest level since 1978, according China Statistical Yearbook 2021. (Photo by Wu Hong/EPA/EFE)

David Martinez, a divemaster and shark feeder, risks life and limb when he hand feeds tiger sharks at Tiger Beach in the Bahamas in December 2022. (Photo by Caters News Agency)

An American white pelican takes flight on the island of Petatan in the municipality of Cojumatlan de Regules, Michoacan state, Mexico on February 23, 2024. The island becomes home to the pelicans during the winter, when they travel from the north of the United States and the south of Canada to the warmer waters of Lake Chapala in Mexico. The birds are a tourist attraction and people gather on the island's boardwalk to feed them and watch them fly. (Photo by Enrique Castro/AFP Photo)

Children jump over a puddle of water as they play during a rainstorm on a street in Barcelona, Spain, Saturday, September 18, 2021. (Photo by Emilio Morenatti/AP Photo)

Shepherd brothers Mustafa Erbay and Baran Erbay train their camels on snowy grounds, enabling them to become champions in competitions held in the Aegean and Mediterranean regions in Baskale district of Van, Turkey on February 1, 2020. (Photo by Ozkan Bilgin/Anadolu Agency via Getty Images)

Morgan Miller carries her one-year-old daughter Mia Jennings in one arm as she shovels the stairs to her Springfield home with the other Sunday, January 13, 2019. Miller said she's learned how to do a lot of things while holding a baby in the last year. (Photo by Ted Schurter/The State Journal-Register via AP Photo)