Nature Declaration of Mayors 2025

As the mayors of the ten largest cities in Finland, we prepared a joint declaration in Tampere on 11 September 2024 to demonstrate our commitment to halting biodiversity loss and enhancing biodiversity. With this declaration, we are updating our common objectives and measures.

We understand the intrinsic value of nature, the significance of biodiversity and recognise the severity of biodiversity loss and the urgency of solving it. Biodiversity is vital to human well-being, safety and health, as it ensures clean air and water, secures functioning soil and food production, as well as helps adapt to the changing climate. We want to foster the shared health of people and the rest of nature. Diverse nature also strengthens the vitality, economy and attractiveness of cities as places of residence and as investment targets. We want to reconcile the enhancing of biodiversity with business activities. We consider it important to preserve biodiversity also for future generations, safeguarding their well-being.

Our cities play a key role in implementing the objectives of the Kunming-Montreal Global Biodiversity Framework and the EU Biodiversity Strategy, according to which biodiversity loss will be halted by 2030 and immediately thereafter turned into a recovery path. As cities, we want to be active actors in this work and in implementing Finland’s future biodiversity strategy. Our actions aim to promote nature positivity, i.e. to produce more benefits than harm to nature.

The role of cities in enhancing biodiversity extends beyond their own actions. Business life, residents, non-governmental organisations, as well as educational and research institutions operating in urban areas produce information and implement solutions to halt biodiversity loss. Cities act as facilitators, pioneers and important partners in this work.

As cities, we have for a long time taken measures to enhance biodiversity and safeguard local nature, and we commit to continuing this work in a more goal-oriented manner. We will comprehensively and diversely adopt practices and methods that promote halting biodiversity loss and develop them further.

The built environment plays a key role in enhancing urban nature, which requires not only our own active contribution but also closer cooperation with the construction industry.

With our example, we want to encourage other cities in Finland and internationally to factor in the safeguarding and enhancing of biodiversity as cities grow. At the same time, we influence climate change mitigation through carbon dioxide sinks and adaptation to it.

In Espoo on 5 September 2025, we made the following updates to the targets and measures agreed in 2024 in Tampere to accelerate our nature actions:

1. We will commit to developing and maintaining the blue-green structure of our cities to support biodiversity and promote the well-being of city residents. In addition to safeguarding local nature, we will also consider the impacts on nature in land use and its planning. We will also strive to take into account our procurements’ impacts on nature.
2. In connection with the 2025 strategy update, we want to bring nature positive targets alongside climate change mitigation. We will investigate what is required of our city to halt biodiversity loss by 2030 and actively implement the measures required to achieve this target. We will set concrete, measurable nature targets for our cities, in which we aim for common practices and maximum comparability. We will implement the principles of the mitigation hierarchy and commit to utilising the common indicators of cities to assess the harms and improvements caused to nature.
3. We will support and urge both the EU and the Finnish government in the preparation and implementation of predictable and long-term regulation that safeguards biodiversity. We see that in order to achieve a feasible result that allows for the special features of the regions, cities must also be strongly involved in implementation planning in growth centres. We will be among the first to promote the introduction of developing operating models that enhance biodiversity, such as ecological compensation in appropriate projects, so that best practices can be established quickly and extensively. To promote practices that mitigate biodiversity loss, we support the creation and use of nature values market.
4. We will combine our resources in biodiversity work and in the preparation of the national implementation plan of the EU Nature Restoration Regulation. We will serve as examples in Finland and internationally by sharing our best practices. We will develop joint initiatives and projects with other cities, urban regions and stakeholders, such as companies, research institutes, non-governmental organisations and resident organisations. We will boost the ambition of nature actions in our international networks by highlighting concrete, measurable actions and the achievements of urban cooperation.
5. We will enhance education and access to information in halting biodiversity loss and emphasise biodiversity in our various services. We will actively communicate about the importance of biodiversity to residents, stakeholders, city personnel and decision-makers alike.
6. Once a year, we will meet at the Nature Forum to assess progress. In 2026, we will meet in Lahti.

In Espoo, 5 September 2025

Kai Mykkänen, Espoo, mayor

Daniel Sazonov, Helsinki, mayor

Timo Koivisto, Jyväskylä, mayor

Soile Lahti, Kuopio, mayor

Niko Kyynäräinen, Lahti, mayor

Ari Alatossava, Oulu, mayor

Lauri Inna, Pori, mayor

Ilmari Nurminen, Tampere, mayor

Piia Elo, Turku, mayor

Pekka Timonen, Vantaa, mayor