The annual census at ZSL London Zoo is in progress with zoo staff and animals facing the cold weather.
Marking the 200th year as a charitable organization, the Zoological Society of London (ZSL) has commenced the task of counting every mammal, bird, reptile, and invertebrate residing at the zoo. Housing over 8,000 animals, ranging from tiny leafcutter ants to massive silverback gorillas, every creature must be tallied.
The yearly census is a mandatory procedure that aids in supporting global conservation breeding initiatives. Amid snowfall in the city and subzero temperatures, workers were captured counting Humboldt penguins, Asiatic lions, corals, Seychelles millipedes, and capybaras on Tuesday.
Dan Simmonds, the zoo’s head keeper, emphasized the significance of this year’s census, coinciding with ZSL’s 200th anniversary. “We have been conducting animal counts at London Zoo for two centuries. It is a crucial day and a wonderful opportunity for visitors to witness the process,” he stated.
“With over 8,000 animals here, there is much to count. Some are straightforward like the two capybara behind me. Despite the -4°C temperature in London today and recent snowfall, the capybara are fortunate to be in their heated shelter, unlike the keepers who are feeling the chill.”
“We anticipate completing the day within a few hours. The counting is extensive, and all data will be logged into an international database shared among conservation zoos worldwide.”
Zoo staff commenced the counting process early on Tuesday at 7 a.m., aiming to enumerate every animal by day’s end. They reported 75 Humboldt penguins, including 16 chicks born in 2025, a positive development for the species’ conservation efforts. Humboldt penguins, originally from Chile and Peru, are classified as vulnerable on the IUCN Red List, facing population decline in the wild.
Additionally, this year’s census included eight Socorro dove chicks hatched in 2025, marking a significant step in rescuing the species from the brink of extinction.
The critically endangered Darwin’s frogs population at London Zoo increased by eight in 2025. As an EDGE (Evolutionarily Distinct and Globally Endangered) species, the birth of these frogs was hailed as a breakthrough by ZSL conservationists leading the international initiative to safeguard the species from the threat of chytrid fungus.
Displayed below are the top images from the annual census at London Zoo.
A zookeeper feeds a capybara during the census at London Zoo
Lions are meticulously counted as part of the census
A millipede undergoes inspection by a London Zoo keeper
Penguins are counted underwater while swimming at London Zoo
A lion seeks warmth as temperatures drop below freezing outside
Penguins are fed fish during the counting process to keep them content
London Zoo is home to two capybara, a new addition to the zoo’s exhibits
With only a few hundred Asiatic lions remaining in the wild, London Zoo proudly houses four of these majestic creatures