Capture — 50 per cent

• Claim filed: “Coral cover in the Great Barrier Reef has declined by 50 per cent in just 27 years.”
• Who: CSIRO (citing De’ath et al. 2012)
• URL: https://www.csiro.au/en/research/natural-environment/oceans/ereefs-management-system
• Date on page: eReefs project from 2012; sentence still live 2026-08-14
• Publisher: CSIRO
• Title: Ensuring a vital future for the Great Barrier Reef
• Captured: 2026-08-14
• Method: saved HTML (csiro-50.html)

Verbatim (CSIRO)

Coral cover in the Great Barrier Reef has declined by 50 per cent in just 27 years.

Footnote 1 is De’ath G, Fabricius KE, Sweatman H, Puotinen M (2012), The 27-year decline of coral cover on the Great Barrier Reef and its causes, PNAS.
https://www.pnas.org/doi/10.1073/pnas.1208909109

The same paper’s second sentence

De’ath et al. attribute that 1985–2012 loss:

• tropical cyclones ~48%
• crown-of-thorns starfish ~42%
• bleaching ~10%

The other meter

Senate inquiry (Ridd) — see evidence/2024/greatest-threat/senate-ridd.html
Ridd: cyclones primarily responsible; some society papers skipped the 2011–2016 recovery after Yasi.

aims-2022.html — northern 36%, central 33%, regional highs in the 36-year record.

aims-2026.html — northern 35.1%, still above the 27% long-term average.

What this file does not do

It does not file “no coral died.” It files the 50 without the storms against a later record high in the same government series.