The rabbit population of San Juan Island, brought in to feed lighthouse keepers, got so big that in the 1930s foxes were introduced to kill them. Although they are red foxes, their coats can be orange, silver, black or multi-coloured. Picture date: September 2023. (Photo by Jun Zuo/Solent News)

China has recently relaxed its one child policy that was used to control a burgeoning population. A couple has their wedding photo taken in an old quarter of Beijing on May 24, 2016. (Photo by Michael Robinson Chavez/The Washington Post)

Sri Lankan participants control their bulls during a traditional cart race to mark the Sri Lanka National New Year in Homagama near Colombo on April 23, 2017. The new year marked by both the majority Sinhalese and minority Tamil population fell on April 14. (Photo by Lakruwan Wanniarachchi/AFP Photo)

Nigerians take a photo in their traditional clothes during Eid al-Fitr prayers in Lagos, Nigeria on May 2, 2022. Muslims gather to perform Eid al-Fitr prayers held in Nigeria, the country with the largest Muslim population in Africa. (Photo by Adeyinka Yusuf/Anadolu Agency via Getty Images)

An Ezo red fox, or kitakitsune, and her cub are seen at night near the city of Sapporo, northern Japan, 15 May 2022. Authorities are calling population to avoid contact with the animals due to risks of echinococcosis infection. (Photo by JIJI Press/EPA/EFE)

A macaque crosses a pedestrian overpass in Hong Kong, China, 08 November 2021. According the Agriculture, Fisheries and Conservation Department, AFCD, the total population of wild monkeys in Hong Kong is about 1,800, distributed in 30 social troops. (Photo by Jerome Favre/EPA/EFE)

Children wearing cardboard lion dance masks walk along a street in Beijing on January 13, 2023. China has announced its first overall population decline in recent years amid an aging society and plunging birthrate. (Photo by Mark Schiefelbein/AP Photo)

Weddell seal numbers in 2025 have declined sharply on Signy Island, part of the South Orkney Islands in the Southern Ocean, where British Antarctic Survey researchers have tracked seal populations for nearly 50 years to understand the impact of melting sea ice. (Photo by Michael Dunn/The Times)