Home / Environment / Rare Algae Bloom Kills Millions, Threatens Extinction
Rare Algae Bloom Kills Millions, Threatens Extinction
15 Mar
Summary
- Massive toxic algae bloom spans 20,000 sq km of coast.
- Millions of sea creatures from 780 species perished.
- Rare Karenia cristata algae linked to the marine disaster.
A year after its first detection, Australia's most extensive algal bloom persists along the South Australian coastline. This rare Karenia cristata bloom has impacted 20,000 sq km, causing mass mortality events unseen in Australia's history and ranking among the worst globally. Over 780 marine species have been affected, with devastating losses reported for the leafy sea dragon, the state's marine emblem.
The crisis has inflicted significant psychological distress on South Australians, with many altering or abandoning recreational activities. Respiratory issues have also been reported following exposure to the bloom. The state's fisheries and seafood industry face severe disruption, with commercial fishing in key areas halted until June 30, 2026, and recreational catch limits reduced.
Scientists detected Karenia cristata, a species previously recorded only in South Africa and Canada, in South Australian waters. While it was present for years, an environmental shift in 2025 caused its dramatic increase. Experts worry the persistent bloom, which has survived diverse conditions over the past year, could reoccur under similar seasonal conditions, threatening marine ecosystems already stripped of life.
