<P> Although these sea slugs live on the open ocean, they sometimes accidentally wash up onto the shore, and therefore they may be found on beaches . </P> <P> G. atlanticus preys on other larger pelagic organisms . The sea slugs can move toward prey or mates by using their cerata to make slow swimming movements . They are known to prey on the dangerously venomous Portuguese man o' war (Physalia physalis); the by - the - wind - sailor (Velella velella); the blue button (Porpita porpita); and the violet snail, Janthina janthina . Occasionally, individuals attack and eat other individuals in captivity . </P> <P> G. atlanticus is able to feed on the Portuguese man o' war due to its immunity to the venomous nematocysts . The slug consumes the entire organism and appears to select and store the most venomous nematocysts for its own use . The nematocysts are collected in specialized sacs (cnidosacs) at the tip of the animal's cerata, the thin feather - like "fingers" on its body . Because Glaucus concentrates the venom, it can produce a more powerful and deadly sting than the Man o' War on which it feeds . </P> <P> Like almost all heterobranchs, Glaucus is a hermaphrodite, having both male and female reproductive organs . Unlike most nudibranchs, which mate with their right sides facing, sea swallows mate with ventral sides facing . After mating, both animals produce egg strings . </P>

Where does the blue dragon sea slug live