That's why many of the zoo's fish, bird and insect species are counted as one group rather than as individuals, as these small and quick moving animals can be quite tricky to count.
This means Colchester Zoo has more than 1,000 individual animals plus colonies and groups of fish, reptiles and other smaller species on site.
Colchester Zoo counting its fish.
- Credit: Colchester Zoo
They also welcomed just over 100 new-borns in 2020, including their large hairy armadillos Allie and Gomez, a beautiful wreathed hornbill and some amazing reptiles from Madagascar such as Madagascan swift lizards and day geckos.
The number of white rhinos that call Colchester Zoo home also increased in 2020 with the arrival of not one but two calves, Lottie and Tayo.