Five creatures take to both the salt water and fresh water: bull sharks, La Plata dolphins, salmon, humans and dinoflagellates.

While bull sharks and La Plata dolphins live in both saltwater and freshwater, salmon are born in freshwater, migrate to the ocean and then return to freshwater to reproduce.

But human swimmers and dinoflagellates interact in an interesting manner that may not be readily apparent.

Ocean swimmers who swim through red tide sometimes feel like they are swimming through a massive can of spilled tomato soup in the ocean.

When the red tide blooms, caused by dinoflagellates or small one cell marine organisms, swimmers usually feel the slime of these organisms on the surface of the water. Andy Seretan recalls, “When we wash out our swimsuits after swimming in the red tide, the red color turns to green as the bioluminescence glow in the dark.”

But when these same ocean swimmers head to a pool, they encounter the dinoflagellates once again in an indirect way. When the dinoflagellate die, their fossilized matter becomes diatomaceous earth. This matter is mined and is used to coat swimming pool filters, serving as minute sieves to remove debris as small as 5 microns.

From red tide to pool side…the circle of life in the open water world is always interesting.

Copyright © 2012 by Open Water Source