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)

People visit a frozen waterfall illuminated by colorful lights at Dadunxia sceneic area on December 25, 2022 in Linxia Hui Autonomous Prefecture, Gansu Province of China. (Photo by Shi Youdong/VCG via Getty Images)

Japanese macaques, also known as snow monkeys, play as they soak in a hot spring in Jigokudani valley in Nagano Prefecture, northwest of Tokyo Saturday, March 6, 2021. (Photo by Kiichiro Sato/AP Photo)

Looking for love by Tony Wu, USA. Highly commended, Animal Portraits. “Accentuating his mature appearance with pastel colours, protruding lips and an outstanding pink forehead, this Asian sheepshead wrasse sets out to impress females and see off rivals, which he will head-butt and bite, near Japan’s remote Sado Island. Individuals start out as females, and when they reach a certain age and size – up to a metre (more than 3 feet) long – can transform into males. Long-lived and slow-growing, the species is intrinsically vulnerable to overfishing”. (Photo by Tony Wu/2018 Wildlife Photographer of the Year)

Greyhounds resume racing behind closed doors on June 01, 2020 in Perry Barr, England. Greyhound racing across England is returning as restrictions on sporting events are relaxed during the coronavirus pandemic. (Photo by Clive Mason/Getty Images)

Hot air balloons are displayed during an exhibition, in Caracas, Venezuela, 09 December 2022. The Government of Venezuela inaugurated an international transport exhibition to attract investment for a sector that has almost been paralyzed for the past five years but has begun to show signs of recovery this year. Venezuela has one of the most obsolete vehicle fleets in Latin America.. (Photo by Miguel Gutierrez/EPA/EFE)

A baby baboon appears to ride its mother like a horse at the Chobe River, in The Chobe National Park, Botswana, Southern Africa in January 2023. Young monkeys often ride on their parent's backs, like this Chacma baboon, for protection. (Photo by William Steel/Solent News & Photo Agency)

These young sloth bears hitch a ride on their mother's back as she forages for food in the Ranthambhore Tiger Reserve in the Indian state of Rajasthan in May 2023. (Photo by Aditya Singh/Solent News)