Many beachgoers feel the sting of a blooming jellyfish population

Key takeaways

Jellyfish stings on Delaware beaches increased fourfold in 2025 compared to 2024.

Over 1,200 jellyfish sting cases recorded this summer; lifeguards use vinegar to treat stings.

Lion’s mane, sea nettles , and moon jellyfish are common species causing stings.

Warmer water temperatures contribute to large jellyfish blooms along the Delaware coast.

LEWES, Del. — More beachgoers have been getting an unexpected shock this summer as jellyfish numbers bloom along the Delaware coast, interrupting — but not stopping — the summer fun.

Beach patrol captains reported a dramatic increase in jellyfish activity and stings in July, the most they’ve seen in recent memory. Lewes Beach reported a fourfold increase in stings compared to 2024.

Lion’s manes, which can have 100-foot