Why does the ocean stink?

Several people in the past few days have asked me why the ocean stinks. The answer is simple. The red tide that I documented a month ago is back, and worse than ever. The culprit is the same, but now it is present in even higher numbers. I can’t show you how it smells, but this is how it looks:

The brown discoloration is due to the high concentration of the dinoflagellate Akashiwo sanguinea. Since the marine lab brings water directly from right about where the waves are starting to crest, our water is also full of the cells. Water coming straight from the taps is tinged with brown, and filters clog like crazy. Animal care has been redefined as “flush, brush, and refill,” as in flush tables, brush or spray globs of brown slime off the animals, and refill the tanks. Only with the water coming in brown, the Akashiwo cells start settling out almost immediately.

This latest bloom of A. sanguinea coincides with the first storm of the rainy season, which could be either good or bad. The first rain causes a big influx of nutrients from land into the ocean–this is good for the blooming dinoflagellates because nutrients are fertilizers. But rain storms come from clouds, and the reduction of sunlight would be bad for photosynthetic critters such as Akashiwo. So what’s it going to be?

Akashiwo sanguinea isn’t a toxin-forming species. However, it does form surfactants when the water is agitated, and the surfactant can be irritating.

Bloom of the dinoflagellate Akashiwo sanguinea at the mouth of Younger Lagoon. 15 October 2016 © Allison J. Gong

Bloom of the dinoflagellate Akashiwo sanguinea at the mouth of Younger Lagoon.
15 October 2016
© Allison J. Gong

See all that foam? When a strong breeze picks up the foam you can smell it. Imagine the smell of rotting kelp, perhaps not quite that pungent, combined with a vague hint of sewer. That doesn’t look quite right but it’s the best I can do. Since I can’t share it with you here, you’ll have to go to the beach and smell it for yourself.

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