City Nature Challenge in Rome (Bioparco)

A friendly competition between the world's cities

The City Nature Challenge is a friendly citizen science competition launched in 2016 by the Natural History Museum of Los Angeles and the California Academy of Sciences, going international in 2018. The mechanism is simple and engaging: over a long spring weekend, residents of more than 450 cities observe, photograph, and upload all the living species they encounter in urban and peri-urban areas to the free iNaturalist platform. Cities compete based on the number of observations collected, species identified, and participants involved; the data is then validated and cataloged by scientists and volunteers, becoming part of an open-access resource for the international scientific community.

Rome: a hub for urban biodiversity

In the Municipality of Rome, in the Lazio region, the event finds ideal terrain: the capital is one of Europe's greenest cities, boasting historic villas, nature reserves, agricultural areas within the Grande Raccordo Anulare, and a river system that weaves through the urban fabric. Coordination for the metropolitan area is handled by the Accademia Nazionale delle Scienze detta dei XL, which publishes an interactive map every year detailing all initiatives organized in Rome and its province.

The most visible hub of the Roman challenge is the Bioparco di Roma, located within Villa Borghese: its 17 hectares become an open-air laboratory for a day, where visitors can observe not only the resident animals but, more importantly, the wild fauna living in the park. Crows, gulls, parakeets, mallards, squirrels, insects, and butterflies are the true stars of the urban safari led by nature experts.

Bioblitzes in the reserves and the Castelli Romani

Beyond the Bioparco, the network of protected areas expands the challenge's reach. The reserves managed by RomaNatura and the Castelli Romani Regional Park offer free bioblitzes and guided excursions: from the Tor Caldara Reserve in Anzio to the Sughereta di Pomezia, and from Tuscolo with park guides to activities in Monte Compatri. These outings are open to everyone, with no naturalistic expertise required: all you need is a smartphone and a desire to take a closer look at what grows and flies around us.

Why participate

• True participatory science: every georeferenced photograph becomes data useful for monitoring biodiversity and managing urban green spaces.
• Family-friendly: children are often the most effective observers, and the playful format works perfectly with schools.
• No barriers to entry: the iNaturalist app is free, many activities in the reserves are free, and those at the Bioparco are included in the admission ticket.
• A new perspective on the city: the challenge reveals how much wild nature coexists with the traffic, monuments, and neighborhoods of the capital.

Rome by the numbers

The results of the previous edition illustrate the vitality of the initiative in the capital: 11,667 total observations, 2,075 species identified, and 494 observers involved, securing a sixth-place finish in Europe and forty-eighth in the world for the number of participants. Rome stands out particularly for its average number of observations per participant, among the highest in Italy: a sign of how deeply rooted and active the Roman naturalist community—including associations, parks, and enthusiasts—truly is.

A spring appointment

The City Nature Challenge always falls at the end of April, when the Roman spring is at its peak: blooming flowers in the meadows of historic villas, returning migratory birds, and pollinating insects everywhere. It is the perfect opportunity to combine a walk through the city's greenery with a concrete gesture of environmental knowledge and protection.