As the Zoological Society of London (ZSL) enters its 200th year as a charity, keepers at London Zoo have started counting every animal for its annual stocktake.
The zoo is home to more than 8,000 animals – from a colony of leafcutter ants to critically endangered Asiatic lions.
ZSL, which runs London Zoo, was founded in 1826 as science-led conservation charity working to protect species, restore ecosystems and help wildlife and people coexist.
Each creature at the zoo is logged as part of the yearly census, which is a licensing requirement and helps inform global conservation breeding programmes.
Recent arrivals have boosted numbers in key species.
In July 2025, the Humboldt penguin colony grew when 16 chicks hatched in a single season – a major conservation win for the vulnerable species, native to Chile and Peru, whose numbers are falling in the wild.
And in April, eight Socorro dove chicks hatched at the zoo, marking a milestone in efforts to save the species from extinction.
Classified as extinct in the wild, there are only 180 Socorro doves left globally, cared for by fewer than 50 conservation institutions.
The population of critically endangered Darwin’s frogs also rose by eight last year. These frogs, an EDGE species (Evolutionarily Distinct and Globally Endangered), are under threat from a deadly chytrid fungus.
ZSL conservationists hailed the births as a landmark in their international project to save the species.
Dan Simmonds, head keeper at the zoo, said: “Everything in terms of conservation that we do here at London Zoo is incredibly important to ensure that we’ve got a safe, long-term sustainable population of, in many cases, critically endangered or in some cases extinct-in-the-wild animals.”
