Bioluminescent Bowl Glow?

     Early on in the research cruise, a scientist reported that while he used the head (the restroom) in the middle of the night with the lights off, he observed a bioluminescent glow in the toilet bowl.  This observation was also confirmed by other scientists on following evenings.  While it was not consistently observed every night, it did occur.  What caused this strange phenomena? Bioluminescent plankton is the culprit!  The ship’s toilets run on a salt water system so when water is pumped in, some of the tiny, one celled organisms called dinoflagellates make their way into your toilet.  They can emit a short blue-green flash of light when the water is agitated by such things as flushing the toilet.  If present in enough numbers a faint glow can be observed.

Many marine organisms possess bioluminescence. While it is not as common in the upper portion of the ocean called photic zone which receives sunlight.  It is estimated that approximately 90% of organisms in the deep ocean, between 200 and 1000 meters, use bioluminescence in some form or another.  It may be used for finding a mate, evading predators, or attracting prey.

 Deep sea organisms have special light producing structures called photophores.  Fish may have  rows of these photophores along the bottom (ventral) side of their body and under their eyes. Some types of angler fish have a bioluminescent lure which dangles above or below the fish’s mouth (a barbel) to attract prey.  Although most marine bioluminescence is not bacterial, the bioluminescence in angler fish lures is created by bacteria. 

Teacher At Sea,

Christia Hewlett

Here are a few more pictures taken by me. The previous pictures were taken by Dr. Dante Fenolio.

Photophores near the eye.

Here you can see rows of photophores along the bottom of the fish.