The City Nature Challenge (CNC) is a large citizen science event covering cities around the globe. It was first held in 2016 by the California Academy of Sciences and Natural History Museum of Los Angeles County. This is a competition that brings cities from around the world together. Citizens of participating cities record local wildlife with the free app iNaturalist. After species identification, the city that records the greatest number of species will win the competition. Data collected during the competition would contribute to the global biodiversity database and assist scientists in ecological research.
Subsequent to 2023 and 2024, OWLHK will continue to be the volunteer city organizer for the City Nature Challenge 2025 (Hong Kong Region). During the period of 25-28 April, the public could take photos of wild animals and plants in Hong Kong. Then, in the period of 29 April-4 May, participants could upload records and identify species. Eventually, the result will be announced on 5 May.
How to participate
- Download the free iNaturalist mobile app and register an account.
- Within the competition period, explore wild animals and plants in the Hong Kong area and take good quality photos.
- Upload the photos of wildlife to iNaturalist and fill in information such as location and date. (Observation records made from 25-28 April 2025 will be automatically included in the Hong Kong CNC project.)
- Species identification: wildlife, including native and non-native species in Hong Kong.
- The observation records will be identified from 29 April to 4 May 2025 and the results will be announced on 5 May 2025.
- Let’s take part in the competition and strive for the championship for Hong Kong!
For more information, please visit the Hong Kong City Nature Challenge website.
Notes
- Please do not submit photos of selfies, pets, indoor or outdoor potted plants, as it may affect the authenticity and accuracy of the database.
- Protect and preserve nature, please try to reduce your interference with the environment, animals and plants during the competition.
iNaturalist User Guideline
Hong Kong Region Result
We would like to express our gratitude to every citizen scientist for their active participation in the Challenge. Among 669 global participating cities, Hong Kong continued to achieve outstanding results this year!
This year, Hong Kong has recorded a total of 5,033 species, setting a new regional record. Hong Kong also ranked the third among all participating cities in the species category! Such a brilliant result was contributed by 1,110 public observers, with 37,571 observation records submitted. Notably, over 45% of the records have attained “Research Grade”. It indicated that the species data collected were of high quality and had great potential for application in relevant research. In terms of species categories, the records of plants and insects were similar to the one in previous year, covering nearly 80% of all, followed by arachnids (i.e. spiders) and birds.
Through the Challenge, we hope that everyone could respect the nature and care for local ecology. Everyone could keep using iNaturalist to record wildlife. Not only could it enhance your understanding of local species, you could also contribute to the ecological database.
Looking forward for everyone’s participation in next year’s City Nature Challenge. Let’s achieve an outstanding result for Hong Kong again!
