Insects in free fall, field birds in decline, oceans under pressure… Behind scientists’ repeated warnings, what do the numbers really say about biodiversity, in France and globally? A survey of a silent but measurable crisis.
For years we’ve talked about it, we know it’s threatened, but we still struggle to grasp its full scope: biodiversity, that is, the entire living world in all its forms (genes, species, ecosystems), is undergoing a crisis that scientists call the 6th mass extinction. Unlike the five previous ones, caused by natural cataclysms, this one has a single origin: human activity. By 2026, official indicators, both French and international, converge on the same finding: the decline continues, and even accelerates on certain fronts.
Across the world: a decline accelerating for 50 years
The global benchmark indicator remains the Living Planet Index (LPI), calculated by the Zoological Society of London for the WWF. Its latest edition, published in 2024, sent shock waves: the average size of wild vertebrate populations tracked worldwide (mammals, birds, fishes, reptiles, amphibians) fell by 73% between 1970 and 2020. This figure does not mean that 73% of animals have vanished, but that the populations observed have lost, on average, three-quarters of their numbers in half a century.
Regional disparities are striking: declines reach 95% in Latin America and the Caribbean, 76% in Africa, versus “only” 35% in Europe — a region where nature had already been heavily degraded before the start of measurements in 1970. Freshwater environments are the hardest hit, with an 85% drop in the populations tracked, ahead of terrestrial (69%) and marine (56%) environments.
On top of that comes the historic IPBES (the biodiversity science platform, the climate‑equivalent for biodiversity): about 1 million species, out of the roughly 8 million estimated on Earth, are currently threatened with extinction, with many of them in the coming decades. More than 40% of amphibians, about a third of reef-building corals, and more than a third of marine mammals are affected.
In France, ongoing erosion despite some progress
France is a special case: with more than 200,000 species documented on its metropolitan and overseas territories, it hosts about 10% of the species known worldwide, placing it among the biodiversity-rich countries — and thus among those bearing the greatest responsibility for conservation.
The 2026 assessment by the indicators of the National Biodiversity Observatory (ONB) and the Ministry of Ecological Transition is unequivocal: the share of species and habitats assessed as “favorable” continues to shrink, falling from about 26% to 22% in recent years. If data gaps are excluded, nearly one in two assessments show a clear downward trend.
Some telling benchmarks:
- Population of birds in agricultural environments has declined by nearly 30% in 30 years, victims of intensified practices and the disappearance of hedgerows and fallow land.
- 19% of freshwater fish species assessed in metropolitan France are considered threatened by the IUCN.
- 84% of natural habitats of community interest are currently in a degraded state, up from 80% six years earlier — soil sealing remains the primary pressure identified on French biodiversity.
- Conversely, some conservation plans are bearing fruit: wintering waterfowl (storks, cormorants…) populations rose by 135% between 1980 and 2025, evidence that nature can recover quickly when pressures ease.
Another encouraging signal on paper: the area of national territory under strong protection now reaches 5.9%, compared with under 2% a few years ago. But this progress is misleading, as it relies almost entirely on overseas territories; on metropolitan France, the rate of strict protection remains below 2%, far from the 10% target set for 2030 under the Montréal COP15 biodiversity framework.
The big forgotten issue: the decline of ordinary biodiversity
While it is easy to be moved by the fate of the boreal lynx, the bearded vulture, or Hermann’s tortoise, the crisis is not limited to iconic species. That’s precisely where the problem lies: the most common fauna and flora — the ones we encounter every day without noticing — are also collapsing.
This ordinary biodiversity — pollinating insects, garden birds, earthworms, wild plants — still provides essential ecosystem services: climate regulation, soil fertility, water purification, pollination of more than 70% of French food crops. As a researcher from Sdes sums up, “it’s not just the so‑called remarkable nature: very common species like the earthworm remain widespread, but their numbers are falling year after year.” A silent decline, therefore, but with real consequences for our food security.
Insects bear a disproportionate share of this quiet erosion. We know for example that insects are indeed disappearing at a worrying rate, and a national citizen-science initiative now measures their decline thanks to the involvement of thousands of volunteers.
A regulatory framework lagging behind
One of the most troubling findings of 2026 concerns the gap between scientific knowledge and regulatory protection. AXA Climate’s study found that only one threatened species in two benefits from legal protection in France, with stark disparities across groups: 95% of threatened birds, reptiles and mammals are protected, versus barely 6% of threatened insects — while the latter, like pollinating syrphids, play a substantial economic and ecological role. This legislative lag illustrates an implicit ranking of life, where the most inconspicuous species remain the big blind spots of conservation policy.
This legal fragility also affects more visible species: take the wood pigeon, whose hunting quota the state recently raised despite an unfavorable conservation status, or waterfowl, for which the LPO is calling for a postponement of hunting in the face of drought.
Climate change, an accelerant of the crisis
Climate change now acts as an amplifier of pressures on ecosystems already weakened by land-use change, pollution, and intensive farming. Its effects are increasingly visible on ordinary wildlife: butterfly migration accelerates with warming, while certain thermophilic species like the praying mantis are expanding their territory in repeated heatwaves — a sign that warming is redrawing, at depth, the map of French biodiversity, to the benefit of some species and to the detriment of many others.
Solutions exist, at all scales
In the face of this, inaction is not a foregone conclusion. National action plans have shown that a protected species can stabilize its numbers, or even rebound — that is the case with the European beaver, whose protection since 1909 allowed the restoration of entire wetlands, with cascading benefits for many other species.
At the individual level too, everyone can act for the ordinary biodiversity surrounding them. A few simple gestures are enough: ban garden pesticides, install nest boxes or insect hotels, leave a patch of lawn to go wild, or create a water feature. ConsoGlobe regularly offers concrete ideas, such as these four simple steps to adopt in spring to help biodiversity. Participating in citizen-science programs (Vigie-Nature, LPO inventories) also allows you to contribute, at your scale, to better documenting the real state of populations — a data set that is today sorely missing for many common species.
The state of biodiversity in a few questions
What is the rate of biodiversity decline worldwide?
According to the WWF’s latest Living Planet Index, populations of wild vertebrates tracked globally have lost 73% of their average numbers between 1970 and 2020. This figure measures a decline in abundance, not a rate of species extinctions.
How many species are threatened with extinction worldwide?
IPBES estimates that about 1 million animal and plant species, out of a total of 8 million described, are currently threatened with extinction in the medium to long term.
What is the main cause of biodiversity decline in France?
Land-use change is identified as the primary pressure on French biodiversity, ahead of agricultural intensification, pollution, and climate change.
Are all threatened species protected by law in France?
No: according to a 2026 AXA Climate study, only 43% of threatened species have legal protection status in France, with wide disparities across species groups.
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