Where Do Box Jellyfish Live? Australia, Asia and Beyond

Where do box jellyfish live in the world?

About 50 species of box jellyfish (class Cubozoa) are known, and new ones are still being described. Almost all of them live in tropical and subtropical waters. They tend to stay close to shore, in places such as sandy beaches, mangrove lagoons, river mouths, coral reefs and kelp forests, rather than in the open ocean.

Most species live in a band from Japan and California in the north to South Africa and New Zealand in the south. The most notorious species live in the Indo-Pacific region, the warm waters stretching from northern Australia to Southeast Asia.

Where does the Australian box jellyfish live?

The Australian box jellyfish (Chironex fleckeri) lives along the tropical north coast of Australia, from around Exmouth in Western Australia, across the Northern Territory, to about Agnes Water in central Queensland. It has also been reported from New Guinea, Indonesia, the Philippines, Malaysia and Vietnam, although scientists now think some of those records may be related species.

Its favorite places are calm, shallow waters off sandy beaches, especially near river mouths, estuaries and mangrove creeks. The young polyps live attached to hard surfaces in estuaries, and each one turns into a small jellyfish at the start of the warm season. That is why adults appear close to the mainland coast rather than on the outer Great Barrier Reef.

In northern Australia, box jellyfish are mainly found in the warm, wet months, roughly October or November to May or June. That period is known locally as the stinger season.

Box jellyfish in Southeast Asia and Japan

Several close relatives of the Australian box jellyfish live farther north. Chironex yamaguchii, the habu jellyfish, was described in 2009 from Okinawa and the other Ryukyu Islands of southern Japan and has also been found in the Philippines. Chironex indrasaksajiae was described in 2017 from the Gulf of Thailand.

These species are also highly venomous. Box jellyfish stings have caused deaths in Japan, Thailand, Malaysia and the Philippines, where rough estimates suggest 20–40 deaths a year, although records are incomplete. Our article how dangerous is a box jellyfish? explains the risks.

Where do Irukandji jellyfish live?

Irukandji jellyfish are tiny box jellyfish, with bells only about 1–2.5 cm (0.4–1 in) across. The best known, Carukia barnesi, lives off north Queensland around Cairns, while Malo maxima is found near Broome in Western Australia. Unlike the Australian box jellyfish, Irukandji also turn up around offshore reefs and islands.

The southern limit of Irukandji stings in Australia appears to have moved over recent decades, with reports as far south as K’gari (Fraser Island) on the east coast and Ningaloo Reef on the west. Other small box jellyfish can cause similar symptoms in Hawaii, Florida, the Caribbean and other warm seas.

Box jellyfish in Hawaii and the Caribbean

Hawaii’s box jellyfish, Alatina alata, is famous for its timing. About 8 to 10 days after each full moon, large numbers come close to the south-facing shores of Oahu, including Waikiki, Ala Moana and Hanauma Bay, to spawn. Lifeguards use a calendar to predict these arrivals and post warnings. The sting is very painful, but no deaths from it have been confirmed.

The same species also lives in the Caribbean, where it gathers to spawn on a similar lunar cycle around islands such as Bonaire. The Caribbean is also home to Tripedalia cystophora, a box jellyfish only about 1 cm (0.4 in) across that lives among mangrove roots in places such as Puerto Rico. It uses its remarkable eyes to find its way; see do box jellyfish have eyes?.

Box jellyfish along US coasts

On the US mainland, the best known box jellyfish is Chiropsalmus quadrumanus, sometimes called the four-handed box jellyfish. It lives in warm Atlantic waters from the Carolinas to Florida, along the Gulf of Mexico to Texas and south through the Caribbean to Brazil. Its bell is about 14 cm (5.5 in) across, and its sting can be dangerous: in 1990 a four-year-old boy died after a sting at Galveston Island, Texas.

Another species, Tamoya haplonema, ranges along the western Atlantic from Argentina north to the US East Coast, with records as far north as Long Island, New York. On the Pacific side, a small box jellyfish, Carybdea confusa, lives in kelp forests off California. Many painful stings on US beaches, though, come from other animals, such as sea nettles and the Portuguese man o’ war, which is not a box jellyfish at all.

Are there box jellyfish in Europe?

Europe has just one box jellyfish, the Mediterranean box jellyfish (Carybdea marsupialis). Its bell is only about 3 cm (1 in) across, with four tentacles up to about 30 cm (12 in) long. It lives in the upper few meters of the sea and is most often seen in summer, sometimes in large numbers at beaches on the coasts of Spain and Italy. Its sting is painful but rarely serious.

No box jellyfish live in the cooler waters of the Atlantic coast of northern Europe, the North Sea or the seas around Britain and Ireland. Outside Europe, other small box jellyfish live off South Africa and New Zealand, near the southern edge of the group’s range.