|Image from ImageQuest|
The stingers of a Man Of War can be dangerous to humans, though are not often fatal. A sting causes immediate redness and burning pain followed by a string of lesions appeared at the sting site. Treatment for a sting involves the careful removal of any remaining tentacle pieces, rinsing with salt water, and the application of topical ointments. It can sometimes take 6-8 weeks for symptoms to fully disappear and more dangerous symptoms, including increased heart rate and difficulty breathing, can arise.
But enough of the scary stuff! The Portuguese Man Of War does have predators despite its nasty sting. Loggerhead Turtles have a fondness for them, as their skin is too thick to be affected by the stingers. There are also a handful of fish that are immune to the venom. This allows them to either eat the Man Of War, or to use it as a safe heaven to hide from other predators.