Submerged Aquatic Vegetation
Scientific name: Zostera marina
Common name: eelgrass
Observed: July 1986
Location: the Chesapeake Bay
The sun is high when we reach the Baltimore harbor, but the camp counselor won’t let us swim. We aren’t even allowed to dangle our fingers in the water. She sends a collection device into the water, brings up the device, and tests the water for chromium, a contaminant dumped into the harbor for years by an old metal processing plant. We’re wowed by the high levels detected. They’re off the chart that comes with the test kit.
The counselor turns the boat around. We head back to our campsite, nestled in a wooded spot upriver. As we leave, I notice the big Domino Sugar sign, hovering above industrial buildings that form the harbor shoreline. The sign will light up in the evening, after we’re gone, in a bright neon red.
Closer to the campsite, the counselor points to a patch of eelgrass waving under the water near the shore. “Submerged aquatic vegetation is important,” she tells us. “It’s a source of food and shelter, and it detoxifies.” The plants absorb the toxins, build them into their fibrous stems and leaves. The harbor is a cauldron of toxins but the eelgrass—the eelgrass cleans.
Scientific name: Halophila hawaiiana
Common name: Hawaii seagrass
Observed: December 2008
Location: A-Bay on the Big Island
I almost don’t notice the seagrass as I swim by. I glimpse a few lettuce-like leaves of it rooted in light-colored sand near the shore. As I move farther from shore, I pass a sea turtle. The soft flesh under its shell has turned green from a diet of aquatic vegetation and algae.
I reach the reef and peer through my mask at the painted city the coral has built, the fishes moving among its mid-rises and along its avenues. After the trip, I’ll learn that some compounds in the sunscreen I’ve applied to protect myself from the sun are toxic to this ecosystem. The compounds can disrupt photosynthesis, preventing algae embedded in the coral from using sunlight to make sugar. Under stress, the algae jettison themselves from the coral, taking their colorful chloroplasts with them. A ghost town remains, skeletal and pale.
Scientific name: Macrocystis pyrifera
Common name: Giant kelp
Observed: September 2017
Location: A marine research station in Monterey, California
I’m guided through a maze of lab spaces crowded with glassware, holding tanks, and centrifuges. I take a seat and stare through a microscope at a kelp embryo. This is what I do—I peer, prod, and experiment. Usually with other life forms, today with kelp.
Kelp in this form looks like a tiny, translucent corn cob. I try to reconcile the speck I see in the microscope with a yards-long rope of kelp I saw on a nearby beach the same morning. As kelp grows, gas-filled buoys form at the base of each leaf. These spheres keep the kelp growing upright, towards the water’s surface, and, therefore, towards the sun. Light is turned to sugar, and sugar becomes both building block and fuel.
Later, driving the Pacific shoreline road, I look down and see kelp fronds waving with the tides in blue-green water. These waters are under threat. But here, holding on, is a forest. It provides food and shelter, and detoxifies.
I want the forest to endure. How sweet. If the kelp forest endures.
Stephanie Mohr is a Massachusetts-based scientist and writer. She is the author of the non-fiction book First in Fly, named one of Smithsonian Magazine's best science books of the year in 2018. She has studied creative writing with Grub Street Center for Creative Writing and was a past participant in Orion Magazine's Environmental Writers’ Workshop. Her creative nonfiction work has appeared online at Black Fork Review, Willows Wept Review, Orion Magazine, and elsewhere.