Habits: These jellyfish normally live in the offshore waters of warm seas throughout the world. They can often be found in large groups. During the warmer months they tend to drift poleward. The Portuguese man of war’s translucent, iridescent float extends 6 inches above the surface of the water and acts like a sail. It can even maintain a course the way a sailboat does.
A jellyfish releases a deadly cloud of poisoned barbs from stinging cells called nematocysts. Once a fish is caught it is drawn up by the muscular stinging tentacles to be eaten by the jellyfish’s feeding polyps.

Habitat: Beneath the Portuguese man of war’s float are clusters of polyps, called a colony. Many tentacles hang from the colony, and some contain stinging cells that paralyze small fish that swim close by. The jellyfish’s muscular stinging cells then lift the prey up into the colony. Special feeding polyps in the colony digest the fish. The Portuguese man of war is not a selective eater. It will eat any fish small enough to be overcome quickly. However, it usually does not attack the small fish of the jack family that helps it to lure and trap prey. A Portuguese man of war drifts in the warm waters off Mozambique. Its trailing tentacles mean certain death for any small fish that may carelessly brush past.

Breeding: The reproductive system of the Portuguese man of war is not fully understood. It is known that the polyps within the colony are responsible for reproduction. New colonies are generated asexually from these polyps. In this way each Portuguese man of war can reproduce itself many times over. This capability may be the reason they sometimes appear in huge numbers. Produced from tiny cells, the Portuguese man of war larvae soon grow to resemble miniatures of the adult.

Special Adaptations: The Portuguese man of war is armed with a great number of tiny stinging cells called nematocysts. Each cell contains a coiled hollow tube tipped with barbs. Any pressure on the cells causes the barbs to be released. They shoot into the prey like miniature harpoons and remain attached to the tentacles. The sting contains a powerful poison similar to cobra venom. Stung fish die quickly.

Key Facts:
Sizes:
Length: Body, 3-14 in.; tentacles usually 45 ft.; on rare occasions tentacles may grow as long as 150 ft.

Breeding:
Reproduction: Usually by asexual budding; polyps break away from the main colony to form new, separate colonies

Lifestyle:
Habit: Marine wanderer; may be found in large groups
Diet: Any small fish
Lifespan: A few months

Related Species: Numerous species in the genus, many known as Portuguese men of war (at least 20 different species recorded in the Mediterranean area alone); close relatives include the by the wind sailor.

Distribution: Found throughout warm seas of the world, the Portuguese man of war is most common in the Gulf Stream of the northern Atlantic and the Indian and Pacific oceans.

Conservation: Little is known about the susceptibility of the Portuguese man of war to oceanic pollution and reduced fish stocks, but at present the species is in no danger.

Features of the Portuguese Man Of War: The large, crested float above water is gas filled and acts as a sail. In stormy weather it can be deflated so that the jellyfish sinks just beneath the water’s surface, where it will be safe from wind and waves. A small member of the jack family of fish can often be found among the tentacles. The fish is immune to the Portuguese man of war’s poison and acts as a lure to attract other fish toward the tentacles. It will then feed on any remains and also on the “dead” ends of tentacles.

Did You Know: A deadly relative of the Portuguese man of war is the bluebottle (P. utriculis), found in the Pacific and Indian oceans. 
Portuguese men of war are related to corals and sea fans.
This jellyfish was given its name by 18th century sailors who reported sighting a creature that looked like a Portuguese ship.

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