0.00°N 0.00°ENASA Blue Marble via GIBS · outline = finding area
Published
Global Red List Index slips to 0.74 in 2025, extending a decade-long decline in species survival
World: Red List Index · seen · published
The Red List Index, which scores species survival on a scale where 1 means no species are threatened, stood at 0.74 for 2025, down from 0.75 in 2024 — a change of -1.33%. Over the last ten years of data the series is worsening at -3.5% per decade. The figures come from IUCN and BirdLife via UN SDG indicator 15.5.1, published through Our World in Data. A re-read of the same source on 27 September 2026 returned the same 0.74, so the number has not been quietly revised.
What this is not: it is not a snapshot of any one place, and it is not caused by the storms, icebergs or wildfires listed alongside it in the same period, nor by the El Niño phase. It is a slow global aggregate that can lag reality by one to five years, and a worldwide average can hide sharp declines in one region offset by recovery in another. The one-year step is small; the ten-year direction carries the weight.
What would change our mind: a revised back-series or a change in upstream assessment method, a 2026 value that reverses the direction, or regional breakdowns showing the decline is concentrated rather than broad.
Written by AI, then checked by a separate reviewer before publication. Every claim points at the evidence below.
What we saw
owid-grapher — Red List Index (species survival): 2025 = 0.74 (2024 = 0.75) index, 1 = none threatened; 10-year trend -3.5% per decade (worsening). Upstream: IUCN / BirdLife via UN SDG 15.5.1. (Jan 1, 2025)See the source ↗
owid-grapher — Re-read on 2026-09-27: 2025 value unchanged at 0.74 — the source has not revised it. Same provider (data stability, not an independent measurement). (Jan 1, 2025)See the source ↗
What it might not be
Confirmation is a re-read of the same provider — data stability, not an independent measurement.
Annual global indicators can lag conditions on the ground by 1–5 years.
A global average masks regional detail: steep local declines and local recoveries can cancel out.
The stated direction is the 10-year trend; a single year can move against it.
Upstream method changes or a revised back-series could shift both the value and the trend.
Uncertainty bands for the index are not shown here.
Annual global indicators lag reality by 1–5 years: a 'new' value can describe a year long past.
The direction is the 10-year trend, not the single year: one year can move against the trend, and the title then says so.
Global aggregates hide where it happens — a stable global number can mask collapse in one region and recovery in another.
Confirmation only proves the source did not revise the number on a later read — same provider, not an independent measurement.
Some series are single sites (ocean pH is Station ALOHA, Hawaii) or modelled composites (Living Planet Index) with wide uncertainty bands we do not show.
Upstream methods change between releases; a revised back-series can make a year look new or change the trend.
What would change our mind
Newer satellite images that show no change, a correction from the data source, or a reply with evidence from the ground. If that happens, the case is marked “Turned out wrong” — in public — and it stays on this site.
Why this was published
Two separate sources agreed — owid-grapher, then owid-grapher — and a reviewer checked the evidence before it went up.
Replies
Know this place? Say what you see. Replies are checked before they appear. No account, no email.
Replies are open on the interactive site (it needs JavaScript).
Red List Index (species survival): 2025 = 0.74 (2024 = 0.75) index, 1 = none threatened; 10-year trend -3.5% per decade (worsening). Upstream: IUCN / BirdLife via UN SDG 15.5.1.