7am The giant cuttlefish and the deadly algal bloom
Aug 12, 2025
In this gripping discussion, marine ecologist Dr. Scott Bennett, who studies algal blooms at the University of Tasmania, shares his alarming findings from South Australia. He details the unprecedented algal bloom affecting the region, leading to the death of over 12,000 marine animals, including rare species like leafy sea dragons and giant cuttlefish. Scott emphasizes the threats posed by rising ocean temperatures and marine heatwaves, urging urgent conservation measures to protect delicate ecosystems from further decline.
AI Snips
Chapters
Transcript
Episode notes
Devastating Firsthand Dive
- Scott Bennett described the dive as one of the most devastating trips he's ever been on.
- He contrasted normal vibrant kelp dives with the eerie, damaged scenes he encountered during the bloom.
Ghostly Reefs And Dead Invertebrates
- Scott said he'd never seen so many dead animals on the seabed, with invertebrates like sea stars and crabs lined up dead.
- He noted reefs were ghostly quiet with many expected fish absent despite some seaweeds remaining healthy.
Unprecedented Multi-Species Toxic Bloom
- The bloom comprises multiple harmful microalgae, notably reported as Karenia mikimotoi, and contains unfamiliar toxins like brevotoxins.
- This event's scale is unprecedented in Australia despite HABs being common annually.