Skip to main content
565 Featured Specimen
Portuguese man o' war

Details

Portuguese man o' war

Physalia physalis

Size
Total length 9–30 m
Diet
Carnivore
Activity
Cathemeral
Sociality
Colony
Lifespan

The Portuguese man o' war is a blue-purple drifting cnidarian with a gas-filled float. It looks like a jellyfish but is actually a colony of specialized zooids.

Range

Habitat range map
Native range Occasional / Transient
Pacific OceanPacific OceanPacific OceanAtlantic OceanAtlantic OceanAtlantic OceanAtlantic OceanAtlantic OceanIndian Ocean

Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)

Details

Habitat

It drifts across warm parts of the Atlantic, Indian and Pacific oceans and may wash near shore with wind and currents. The surface float acts like a sail.

Appearance

The float is usually about 10-30 cm long, while tentacles may trail for several metres and sometimes much farther. Blue, violet and pink tones make it conspicuous at the surface.

Behavior

It does not swim against currents. Different zooids handle floating, feeding, digestion and reproduction within the colony.

Feeding

Small fishes and crustaceans are captured with stinging cells. Long tentacles entangle prey and venom helps immobilize it.

Reproduction

Reproductive zooids produce eggs or sperm, and the life cycle includes small developing stages. Ocean currents disperse the species over wide areas.

Notes

Even stranded animals can still sting, so they should not be touched on beaches. Mass strandings can close swimming areas.