Target (Environment Act): halt the decline so that species abundance in 2030 is higher than in 2022 (65.4 on this index), then by 2042 at least 10% higher than in 2030. Below the 2022 line counts as off track.

What it means: an average of population trends for over a thousand species of birds, butterflies, moths, bats, mammals, bees, plants and others with good long-term records. On average, these species are roughly 40% less abundant than in 1970. Defra calls this an official statistic in development, so the method may change, and the latest years are the least certain.

Source: Defra, indicators of species abundance in England (May 2026), worksheets 1 and 4; target from the Environmental Improvement Plan 2025.