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SpongeBob’s Aurora Borealis – San Diego’s Red Tide

Over the last few weeks in the San Diego area (and I’m guessing several locations within a few tens of miles from there, too), a strange thing has been happening – at night, the tide is glowing.  The rolling waves of water are emanating a crazy dim glow, almost as if it’s dreaming – whenever I see the ocean in my head, it’s always sleeping, I have no idea why.  Check out this amazing video:

Meet the little dinoflagellate that’s causing all of this awesome low-level illuminating beauty:

This is Lingulodinium Polyedrum, also known as the little dinoflagellate that is responsible for Red Tides and mollusk death during these periods of “red” tides, is not poisonous to humans, according to biological oceanographer Peter Franks.  Dr. Franks teaches at the University of Southern California at San Diego, and is a pretty intelligent dude.  I came across an article that was a back-and-forth email exchange between Dr. Franks and Miriam Goldstein of Deep Sea News.  On the subject of Red Tides making you sick and WHY they are bioluminescent:

Frequently asked question number 2: Why do the dinoflagellates bioluminescence?

As far as we know (which is surprisingly not very far) the bioluminescence both deters grazers of the dinoflagellates (who likes eating food that flashes in your mouth?), and also attracts the predators of the grazers which are mostly visually oriented organisms such as fish (the so-called “burglar hypothesis”).

Frequently asked question number 3: When I surf in a red tide I get sick (ear aches, sinus infections, etc.). Why?

My usual answer is that you should bathe more. Or at least check to see whether you get sick when there isn’t a red tide.

However … a student of mine (Meg Rippy – please give her a postdoc) has some evidence that red tides can decrease the mortality of human pathogenic bacteria that get into the nearshore waters. These bacteria normally die pretty quickly; they may die slower during a red tide, perhaps due to the increased amounts of organic material in the water. So perhaps your ear infection is because of other bacteria that are present in higher concentrations in a red tide than they would normally be. (Please give us funding to pursue this.)

It seems as though this is something that will have more explanation in the future as we discover more about the dinoflagellates and how they chemically interact.  Stay tuned!

Dr. Franks had a cool experiment to try – get a clear bottle and fill it with knee-deep tide water.  Take the bottle home and stick in the dark for a few hours, and then shake it in the dark.  The Lingulodinium Polyedrum will release some bioluminescent material into the water!  If you add ammonia, says Dr. Franks, all of the Lingulodinium Polyedrum will dump ALL of their bioluminescent material all at once, like a little fireworks show in a bottle!  This is, however, terminal to the dinoflagellates.  If this kills your conscience, don’t do it.  I, however, cannot wait to have some blue fireworks in a bottle!

Thanksa, Species Identification!