Overview
- The Sandringham Life Saving Club closed the beach on Sunday, urged people to avoid the water, and said patrollers would be on hand.
- Footage shared by the club showed a large bloom in the bay, with reports of hundreds at Sandringham and sightings along the eastern shoreline.
- No injuries were reported in the coverage, though stings can cause intense pain, redness and itching, with severe allergic reactions possible for some people.
- Marine biologists say summer conditions drove the surge: water above 18°C, a nutrient pulse after rain flushing the Yarra, and strong westerly winds focusing the jellyfish near eastern beaches.
- The local lion’s mane subspecies is native and relatively small but has tentacles up to about 1.5–2 metres that can still sting when detached or washed ashore, so swimmers are advised to stay out and follow first‑aid guidance if stung.