Dolphin deaths in South Australia spike after algal bloom decimates food sources

The March 2025 marine disaster may be linked to a high number of dolphin deaths in the region, scientists say

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The number of dead dolphins washing up on South Australian beaches spiked in 2025, according to long-term data that reveals mortalities during the state’s devastating algal bloom were the highest in 12 years.

Last year, at least 70 carcasses of common and bottlenose https://www.theguardian.com/australia-news/2025/aug/13/south-australia-algal-bloom-albanese-government-response-black-summer-era-fast-track-dolphin-beach">dolphins were found across South Australia, with a further 20 reported in 2026, including the recent death of a https://www.abc.net.au/news/2026-06-12/port-river-dolphin-zoom-death-being-investigated/106791044">popular Port River dolphin known as Zoom.