Deep in the Seaweeds

Maine author Susan Hand Shetterly takes readers on a captivating trip through the world of underwater flora.

Deep in the Seaweeds
shutterstock | Kichigin (seaweed)
By Will Grunewald
From our September 2018 issue

Beachgoers, boaters, fishermen — for many a recreationalist, seaweed is mostly just a nuisance. But in Seaweed Chronicles: A World at the Water’s Edge (Algonquin), seaweed gets its due as the fascinating, vital — and, unfortunately, threatened — lifeform it is. Here, five of the most mind-blowing facts from the pages of Shetterly’s ode to those slimy sea veggies.

1.  Migratory birds use drifting patches of seaweeds as “rest stops” on the open ocean, picking small, edible creature out of the tangle for a quick snack.

2. Young eels swimming to Maine, one of only two states with an elver fishery, were all spawned in Sargasso Sea, an area of the North Atlantic with an ecosystem defined by dense Sargassum seaweed.

3. In 2016, 17,367,229 pounds of Ascophyllum nodosum — more commonly called rockweed, often used in fertilizers and feeds — were harvested in Maine.

4. Photosynthesis from seaweed generates at least half of the oxygen in Earth’s atmosphere.

5. FMC Corporation, with its Rockland processing plant, is the only company to manufacture food-grade carrageenan — a seaweed extract found in almond milk, tofu, shampoo, and toothpaste — in the U.S.

April 2025 cover of Down East magazine: A bouquet of poppies and beets.

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