>>the south-shore of Oahu gets a bunch of box jelly fish...
Didn't know that. There are multiple variants so from your description, I wonder whether you get the awful version seen in Australia that can blind or kill. Its transparent body can be the size of a basketball with each corner sporting a trailing tendril 2 or 3 yards long, which is what delivers the injury. You can't expect to see it or avoid it- in fact, for years people weren't sure what was causing sudden agony and death in Australian waters.
Meanwhile the ghastly-looking Portugese Man-O-War causes 10,000 stings on Aussie beaches in summer, but rarely kills.
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1
