A 73% average decline in wildlife populations: an overview of the 2026 Living Planet Index report
A guide to understanding the Living Planet Index and what it does and doesn’t mean..
The Living Planet Index (LPI) is a report published by the World Wildlife Fund (WWF) that tracks changes in the populations of thousands of wildlife species over time. The 2026 edition, released on October 8, 2026, calculates an average decline of 73% in studied wildlife populations since 1970. The LPI focuses on vertebrates like mammals, birds, reptiles, amphibians, and fish, but does not yet include invertebrates or plants. It is updated every two years using data from over 35,803 populations. The index is designed to provide a broad overview of biodiversity trends rather than measuring extinctions or species loss directly. Researchers collect population data from various sources, calculate the rate of change for each population, and then compute a geometric mean to produce the final LPI figure.
The headline figure of a 73% average decline does not mean that 73% of species or populations have gone extinct or are declining. Such interpretations are incorrect and misrepresent the data. The LPI measures the average decline across all studied populations, not the proportion of populations in decline. In fact, the report shows that exactly 50% of the studied populations are decreasing, while 43% are increasing and 7% are stable. The 73% figure reflects the magnitude of decline in populations that are shrinking, not the share of populations experiencing decline. For example, a population that drops from 1,000 to 270 individuals would contribute to the 73% average, even if other populations are growing. The LPI authors emphasize this distinction to avoid misunderstandings in media reporting.
The LPI is calculated by collecting population data for thousands of wildlife species over time. Researchers measure the change in population numbers relative to a baseline year, typically 1970, though many datasets span shorter periods. For each population, the rate of change is calculated, which can be positive (increasing), negative (declining), or zero (stable). The final LPI figure is derived by taking the geometric mean of these rates across all populations, which accounts for the compounding effect of declines. Different populations are also weighted based on factors like data quality and species representation. This method ensures that the index reflects overall trends rather than being skewed by a few extreme cases. The 2026 report includes data from 35,803 populations, an increase of about 1,000 from the 2024 edition.
The 2026 LPI report shows the same average decline of 73% as the 2024 edition, but this does not mean wildlife populations dropped by 4 percentage points in the last two years. Instead, the entire trend line has shifted due to improvements in data coverage and the inclusion of new populations and species. Since the 2024 report, the number of populations studied increased by 3% (about 1,000 additional populations) and the number of species by 5% (about 300 additional species). Notably, the 2026 report includes a significant increase in data from Africa, with a 14% rise in populations and a 38% rise in species, addressing prior underrepresentation. The updated data has adjusted the overall trend, but the fundamental pattern of decline remains consistent across reports.
While the average decline across all studied populations is 73%, the trends vary by region and species group. The LPI 2026 report includes data from different geographic regions, and the decline is not uniform. For example, the number of populations and species from Africa increased substantially in this edition, reflecting a deliberate effort to improve data representation. Within taxonomic groups, the share of declining populations also differs. Amphibians and birds, for instance, have larger shares of declining populations compared to mammals or reptiles. This variation highlights the importance of targeted conservation efforts, as some species and regions face greater challenges than others. The data suggests that while some populations are thriving, others require urgent attention to prevent further declines.
The LPI data reveals that not all wildlife populations are in decline, with nearly half either stable or increasing. This nuance is critical for conservation strategies, as it allows resources to be directed more effectively toward populations in serious trouble. For example, if a species is declining rapidly in one region but stable in another, conservation efforts can focus on the declining population. The report emphasizes that understanding why some populations are increasing while others are decreasing is essential for developing targeted solutions. This approach is more efficient than assuming all populations are struggling uniformly. The LPI serves as a tool for policymakers and conservationists to identify priorities and measure the impact of their efforts over time.
