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Name: Thomas
Status: other
Grade: other
Location: FL
Country: USA
Date: October 2008

I am a doctor and walk the beaches where I live all the time. we saw in the surf a lime green color about half the size of a football field.It was absolutely beautiful. The rest of the surf was it's normal color. we had people coming up to us asking if we see the green color When we returned to the area later it was gone I could not come up with an explanation What causes this?

Hello Thomas,

This phenomenon you observed was most likely caused by "bioluminescent" dinoflagellates, as these microorganisms are known to produce the effect of emitting light when they are disturbed. These are also known as marine plankton or phytoplankton. Examples of these creatures are the species that create "red tide" which is harmful to fish and irritating to people. However, not all dinoflagellates are dangerous, nor do all dinoflagellates exhibit this glowing effect. For the species that do luminesce, when they are in heavy bloom, you can sometimes observe that crashing ocean waves "glow" at night as well. It is thought that this may be a means of communication between the organisms called "quorum sensing"; which may aid in behavior coordination.

Hope this helps,

Joel Jadus

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