The City Nature Challenge o Urban Naturalist Challengecreated in 2016, has become one of the largest community science events in the world because it helps to better understand, and therefore care for, the nature that lives in and around urban areas.

This contest allows people from anywhere in the world to participate by photographing and recording species of animals, plants and fungi that exist in their region.

The 2023 edition took place from April 28 to May 1 and Sinaloa had an outstanding participation, since Mazatlan y Cosalá finished among the top 10 cities in the world in participation.

Mexico was the second country with the highest participation in this challenge, with 77 of the 482 cities registered, gathering more than 210,000 observations of more than 11,000 species.

The City Nature Challenge 2023 recorded 1.8 million observations of flora and fauna worldwide, thus increasing year by year the number of species recorded and involving a greater number of people. A little more than 57 thousand species were recorded worldwide, including rare, endangered or threatened species, and more than 66 thousand people participated.

Mazatlan ranked fifth, ahead of cities such as Houston, Hong Kong and New York, recording 42,431 observations, with 2,553 species. With 607, the white-winged dove was the most observed.

Cosalá finished in ninth place in observations, with 35,800. The most observed species was the pitahaya, with 359 records.

At the national level, the state of Sinaloa contributed 50% of the observations with 14 participating municipalities.

La Paz, Bolivia, with more than 128,000 observations, was the winner of the City Nature Challenge 2023.

In 2023, the platform NaturaLista has been active in Mexico for 10 years and has positioned itself as the largest citizen science social network for nature observation. Currently, it has more than 5 million registered observations of more than 47 thousand species, almost 50% of those living in Mexico.

The registration of photographs of nature on the NaturaLista digital platform makes it possible to know which species are present in a city or municipality, where they are located, which are endemic or exotic, to help study them and protect those that are at risk. The photographic records of species are part of the National Biodiversity Information System and can be consulted at EncicloVida. www.enciclovida.mx.

The City Nature Challenge allows for the combined efforts of all citizens (scientists, environmental authorities, academics, students, civil society organizations, rural communities, media and the general public) to find and document the nature of localities throughout the country.

Sources: Naturalist, Conabio