Across the globe, the collapse of biodiversity continues at an ever faster rate. Wild vertebrate populations fell by 73% between 1970 and 2022, according to World Wildlife Fund’s Living Planet Report 2026. In the latest edition of its Global Red List, the International Union for Conservation of Nature lists, out of 175,909 species studied, 49,505 species – nearly a third – threatened with extinction: 44% of reef-building corals, 41% of amphibians, 38% of sharks and rays, 38% of trees, 26% of mammals and 11% birds.
Against this backdrop of urgency, the COP17 on biological diversity takes place from October 19 to 30, 2026 in Yerevan, Armenia.
This is the 17th conference of the 196 States Parties to the Convention on Biological Diversity, signed at the Rio Earth Summit in 1992. Its main focus is follow-up to the Kunming–Montreal Global Biodiversity Framework, adopted at COP15 in 2021–2022.
Laying out objectives for 2050, this document sets 23 quantified targets to be met by 2030, including: restoring 30% of degraded areas; protecting 30% of land and seas; halving pesticide-related risks; a reduction in subsidies harmful to biodiversity amounting to $500 billion per year; and the transfer of $30 billion per year from developed to developing countries.
Failure to act on the scale of the crisis
But with four years to go until the 2030 deadline, these targets seem out of reach: the draft Biodiversity Action Report, due to be published at COP17, highlights a significant delay. “Collectively, we are not acting on the scale required,” says Astrid Schomaker, Executive Secretary of the Convention on Biological Diversity. “To achieve the targets, we need a response from societies as a whole.”
Under the 1992 Rio Convention on Biological Diversity, as well as the climate change convention signed in the same year, it is indeed States that are bound by international law to halt the loss of biodiversity.
However, the latest report from IPBES (the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services) -- biodiversity equivalent of the IPCC -- highlights the responsibility of companies in this mass extinction of species, in the same way that the Carbon Majors report highlighted in 2017 the responsibility of fossil fuel companies in climate change.
As many legal actions as threatened species and habitats
It is therefore tempting to see a parallel with legal action taken by climate NGOs. Whilst climate lawsuits have sanctioned certain States and called on them to reduce their greenhouse gas emissions, could biodiversity lawsuits accelerate global action for biological diversity?
Answering this question is not easy: unlike climate lawsuits, which are tracked in a benchmark database by the Sabin Centre for Climate Change Law at Columbia University in New York, there is no regularly updated database of biodiversity lawsuits.
In addition, “the most common biodiversity litigation cases focus on local threats, and/or protected species and protected areas,” say Guillaume Futhazar, Sandrine Maljean-Dubois and Jona Razzaque in their book entitled Biodiversity Litigation. They are thus limited to specific instances of biodiversity loss, such as deforestation caused by an infrastructure project, poaching of a species, and so on. These case-specific legal actions are countless in number, becoming a staple of environmental action since nature conservation laws were enacted from the 1970s onwards in most OECD countries.
By contrast, climate lawsuits, which emerged in the 2000s, tackle a global phenomenon and are overwhelmingly aimed at reducing a single factor: greenhouse gas emissions, the main cause of climate change.
In an attempt to draw a more robust comparison between these two types of lawsuit, Rebecca Fenn, a researcher at the TransLitigate Project at Tilburg University in the Netherlands, has compiled a database of 214 more structural biodiversity cases that focus not on an isolated instance of biodiversity loss but on some of the large-scale causes, whether within a given country or attributable to a specific multinational corporation. In an article published in the Journal of Environmental Law, she analyses these 214 biodiversity cases: nearly half, she notes at the outset, were brought before national courts in France (40) and Germany (24), or before the European Union (39).
Eight possible legal strategies
In her analysis, Fenn identifies eight strategies for action.
- Force states to enforce biodiversity regulations they have themselves enacted, such as reducing deforestation in the Brazilian Amazon and reducing nitrogen oxide pollution in the Netherlands.
- Counter legal rollbacks in biodiversity protection, such as exemptions from anti-pollution regulations in French Guiana and regressive European Union directives on the development of renewable energy.
- Introduce biodiversity criteria into public authorisations, such as on fishing in Ireland and tree felling in the Philippines.
- Prioritise biodiversity criteria in public authorisations, such as in the pesticides market in France and in Guatemala’s mining code.
- Cut off funding for “ecocidal” projects, e.g. by targeting certain international investments by banks like the Royal Bank of Scotland in the United Kingdom and BNP Paribas in France, as well as those by insurance companies.
- Ensure that large companies fulfil their duty of care, such as on supply of meat to French Casino supermarkets from Brazil and Colombia and on the sale of pesticides and soya beans by German agrochemical company Bayer in Latin America.
- Hold Heads of State or corporate executives personally accountable for serious damage caused to both the environment and people: chlordecone pollution in the French West Indies; and deadly deforestation of the Amazon under the presidency of Jair Bolsonaro in Brazil.
- Take legal action to force “government framework cases [that] challenge the inadequacy or absence of biodiversity targets or policies that concern the whole of a country’s economy or society”.
BUND’s action in Germany
This eighth strategy identified is the most systemic: it has been used particularly by BUND, the German Federation for the Environment and Nature Conservation.
In a biodiversity complaint lodged in October 2024 with the German Federal Constitutional Court, BUND draws on a landmark climate ruling handed down by that same court in March 2021. According to this ruling, the German Climate Act is insufficient to guarantee the complainants’ constitutional rights and “fundamental freedoms”, and exposes future generations to “serious losses of freedom”.
BUND’s biodiversity complaint draws on this line of argument from the Constitutional Court’s climate ruling to secure, in the name of “human rights”, a federal framework for action in favour of biodiversity, and in particular a government plan to combat “excessive intensive livestock farming, over-fertilisation and the excessive use of pesticides”. The current German law “effectively legalises the destruction of ecosystems”, the complaint asserts, whereas “the factors causing destruction must be systematically combated”.
This biodiversity complaint by BUND is still under consideration, with the organisation having submitted its latest written submission in June 2026.
Notre affaire à tous acts in France
The BUND case, which draws on national climate case law to secure a favourable ruling on biodiversity, is not an isolated one. In France, in February 2021, the organisation Notre affaire à tous secured a ruling from the Paris Administrative Court ordering the State to publish a more stringent and detailed strategy for reducing greenhouse gas emissions, on grounds of “ecological harm”.
A few months later, it lodged an appeal entitled “Justice for Life”, based primarily on this same concept of ecological harm, to compel the State to tighten its environmental requirements for marketing pesticides. After being successful in the lower court in June 2023 and subsequently before the Administrative Court of Appeal in September 2025, this appeal is still pending before the Council of State.
Whilst organisations that win climate-related legal actions tend to take more in the biodiversity field, there is as yet no international network of the kind that formally exists like the Climate Litigation Network.
Biodiversity damage as a violation of human rights
In an article published in March 2024, legal scholars An Cliquet and Frank Maes of Ghent University note that “it would be interesting to see more strategic biodiversity court cases which, alongside climate litigation cases, argue that governments should do more to fulfil their obligations under international environmental law. Such cases could also base their arguments on the ground that failing to protect and restore biodiversity constitutes a violation of human rights”.
This movement will no doubt be boosted by the International Court of Justice advisory opinion of 23 July 2025, which brings together all States’ environmental obligations under the concept of the human right to a healthy environment. This new human right can be invoked before national courts to secure more binding judgements. Anne-Sophie Denolle, a lecturer and researcher at the University of Rouen and co-editor with Christel Cournil of the book Le droit : une arme au service du vivant ?, points out that “in the face of environmental backsliding, the judge acts as a bulwark in defence of living beings, who can increasingly rely on that for their fundamental rights”.
