After last year's record red tide in New England, the research ships were out early this spring. I got to go along on a sampling trip in early April. We took Woods Hole's R/V Tioga and spent the day in Massachusetts Bay hauling water on board and sampling it for tiny Alexandrium cells.
Red tides (more appropriately called harmful algal blooms because they're not always red) happen when some particular phytoplankton (including Alexandrium) multiply into great numbers. Each cell produces a very tiny amount of toxin as a byproduct of its daily routine. The output is so little that they're not harmful as long as they stay in the water; the trouble starts when filter feeders like clams and oysters concentrate the cells into even greater numbers. Eventually, you eat a clam, you get paralytic shellfish poisoning, and you suffocate. Yikes.
Fortunately for all you chowderheads, newly developed models indicate we probably won't have nearly so bad a red tide season this year. On our sampling trip in early April there were very few Alexandrium in evidence. This picture is the tops of the Niskin bottles we used to sample water. We snap those lids shut at precise depths to capture a discrete sample of water. Then someone with a strong stomach, like Bruce Keafer, hunches over a microscope belowdecks and picks through the algae soup looking for Alexandrium. The rest of us look at the sun going down behind Cape Ann.
And, okay, here's one more. Just before quitting New England for the shores of Monterey Bay, I got a classic low-tide harbor shot. This one is at dawn in Rockport, Mass. File under "quaint."