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

At least 90 dolphin carcasses have been found in South Australia since 2025, with researchers attributing the spike to food shortages caused by a severe algal bloom.

• At least 70 common and bottlenose dolphin carcasses were recorded in 2025, with 20 more reported in 2026, including a Port River dolphin named Zoom.
• Many carcasses in Gulf St Vincent, heavily impacted by the bloom, showed severe emaciation, according to researchers.
• Dr Catherine Kemper said dolphin mortalities in the gulf in 2025 were the highest since 2013, when morbillivirus affected dozens of dolphins.
• A state government spokesperson said disruption to marine food chains was a potential contributing factor to the increased deaths.