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Purple nocturnal roving jellyfish!

  1. Jul 8, 2005 #1

    JamesU

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    I had an attachment, but the file was too large. :frown: the topic should change quicker now..
     
  2. jcsd
  3. Jul 8, 2005 #2
    You've got your syntax all wrong. It's: nocturnally roving, weird, purple jellyfish. And, indeed, since they only do this en mass it's: "nocturnally roving herds of weird, purple jellyfish."


    I've been down to the beach here the last three mornings and have been completely amazed by the greatest amount of weird, purple jellyfish activity I have ever seen. You can't walk twenty feet without encountering a piece of a purple jellyfish. Some are just blobs of purple jelly, some are torn pieces of jellyfish bells, and others are detached tentacle assemblys, all laying there with the seaweed and other sea stuff on the beach. I thought some giant Navy ship must have plowed through a massive school of them just off shore and chopped them to pieces with its huge propellers.

    However, yesterday, I heard a guy talking to a guy at a coffee shop pointing out to him how the water in the crest of the waves looks dirty and dingy. This, he explained, was because we were experiencing a "red tide". A "red tide" he said, was a kind of infestation of the water by a particular kind of microscopic plankton that occurs from time to time. Up close, I observed that the sea foam has a distinctly yellow ochre color instead of the usual white. I suppose that is the "red tide" and now I suspect this is what's been killing all the weird, purple jellyfish.
     
  4. Jul 8, 2005 #3

    honestrosewater

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    Had you never heard of red tide before? :eek: I thought you knew everything. :wink: So maybe red tide killed them, but how were they chopped into pieces? Are there turtles around?
     
  5. Jul 8, 2005 #4
    I thought red tide only affected shellfish.

    Anyway, even if it does affect the jellyfish, it wouldn't rip them apart.
     
  6. Jul 8, 2005 #5
    I'd heard the term and maybe even that it was a plankton thing, but I guess I'd assumed it would actually look quite reddish. The water merely looks "dirty" as though there is alot of loose, silty stuff in suspension in it. I would have suggested "Ochre Tide" had anyone bothered to ask when they were naming it.
    I do, but omniscience isn't what it's cracked up to be.
    There are no turtles around here. My speculation is that the dead jellyfish must be getting torn apart by being washed back and forth against the sand by the waves for hours before they actually end up getting permanently beached. Last year I saw a couple of them going back and forth in the waves like this for several minutes before I got sick of waiting for them to finally land.
     
  7. Jul 8, 2005 #6

    Math Is Hard

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    Perhaps they were sucked up in a waterspout,
    whirled wildly about,
    until they made a clumpy purple puree
    spread across San Diego Bay?
     
  8. Jul 8, 2005 #7

    honestrosewater

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    It looks pink to red to brown in the pictures I've seen- and faint to very noticeable.
    Yeah, tell me about it. :rolleyes:
    I think some experiments are in order. How much power does it take to rip apart a dead, nocturnally roving, weird, purple jellyfish? It may be dangerous, but I'm willing to volunteer you. :biggrin:
    (Of course, being omniscient, I already know this, but we still must satisfy the scientific community.)
     
  9. Jul 8, 2005 #8

    JamesU

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    this thread has officially changed topic ;)
     
  10. Jul 8, 2005 #9
    I believe the anser is dependent on the extent to which the "red tide" degrades the corpus jellicus in killing it, if that is indeed the cause of all this.

    Another suspect I didn't think of is the unbelievably hot weather. It could be the water is too warm for them close to the shore. Or: it could be nothing killed them exept getting washed back and forth in the surf. They may have been swept in too close by a freak current.

    Anyway, I was out there today again, and there aren't any new ones around. Most of the ones that were there yesterday are gone as well. The first day I went to the beach was July 5 and they were already there. (My first thought, of course, was that they really can't take fireworks.)
     
  11. Jul 8, 2005 #10

    Math Is Hard

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    Fireworks? Do you 'spose people were blowing them up?

    Then again, I remember that story about the exploding frogs. Could have been freak natural phenomena. Did anyone ever figure that out?
     
  12. Jul 9, 2005 #11
    No, I was thinking the jellies were just too sensitive for things like The Fourth Of July auditory bombardment, and were stunned into unconsciousness by it all.
     
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