More than 100 species of jellyfish have been recorded along the Great Barrier Reef, including the notorious stinging blue bottles and box jellyfish. One of these, the infamous Irukandji jellyfish, is one of the smallest (roughly one cubic centimetre) and most venomous jellyfish in the world.

Yes, box jellyfish (specifically Chironex fleckeri) and the smaller Irukandji jellyfish are present in the waters of the Great Barrier Reef, particularly in the Tropical North Queensland region. However, they are primarily "seasonal," appearing most frequently during the "stinger season" which runs from November to May. While box jellyfish are more common in shallow coastal waters and estuaries, Irukandji can be found further out on the reef. In 2026, safety protocols are very advanced; most tour operators provide "stinger suits" (lycra suits) that provide 99% protection against stings. Additionally, popular swimming beaches have stinger nets and "vinegar stations" for emergency treatment. While the presence of these venomous creatures is a reality, fatal incidents remain extremely rare due to high public awareness and effective medical response.