The drive from Atlanta to the Georgia coast is a relatively long one, at just around four hours. Thankfully, it's also a relatively easy one, because the journey is mostly via I-16 and I-75. That's a contrast to the laborious trek east from Athens, which snakes around on state highways, passing through one-horse towns where the speed limit plummets to 25 mph. Either way, the route takes me through Savannah before dropping south along the coastline to Midway, where I catch my boat to the island. It's right about the time I hit Savannah that I can sense a change in the air.
Even from inside my air-conditioned Hyundai, windows rolled up, I can smell a hint of salt in the breeze. Despite the briny overtones, this air is somehow fresher, cooler (at least, more fresh than what I've been breathing off the highway for two hundred miles). The scent reminds me of vacation. I think I've mentioned growing up landlocked; as a kid, I only ever saw a beach when we visited family. As an adult, I've restricted my escapades to tropical beaches when they didn't involve school (and sometimes when they did). Still, three and a half months along my internship, the tingle of salt and seaweed in my nostrils conjures nostalgia for exotic locales. If I ate seafood, that tingle would likely make my mouth water too. It smells like oysters on the half shell, pulled straight out of the water.
Once I'm parked and have been delivered by boat to the St. Catherines Island west dock, there's another aroma that drifts my way. It comes in from the marsh and has quite a different character. Maybe "aroma" isn't the right word. Yes, I think "stench" is a bit more adequate. I can sense the same saltiness, but there's a strong element of rot. Instead of far-off locations, this odor brings to mind the collard greens that routinely go bad in the commissary refrigerator. Despite the myriad of products we store in our industrial-sized coolers - things like dead mice, eggs, wet dog food, brown bananas, and the pink stuff I suspect is made from horse meat - hands down the most offensive stench comes from the lettuce and collards that have turned. There's a similarity in the scents probably because both emanations are the result of decaying plant matter. But, what's decaying out in the marsh is probably one of the most valuable plants we have.
Its scientific name is Spartina alterniflora (two words I can inexplicably still recall although it's been a nearly year since we discussed this organism in my field ecology course last May). S. alterniflora is more commonly known as smooth cordgrass, saltmarsh cordgrass, oystergrass, or saltwater cordgrass. It makes up at least fifty percent of the island itself, primarily along the southern and eastern shores. It also covers most of the territory between here and the mainland (check out the satellite version of the map on my home page). The plant is what ecologists like myself call an "ecosystem engineer," meaning that it creates or alters its own habitat, which in turn affects the organisms around it a great deal. This grass greatly affects my own habitat, aside from its rotten ambiance. The marsh is the main reason why St. Catherines isn't just a tiny sliver of land; it buffers erosion. It filters out toxic materials and traps sediment. In fact, the grass has been transplanted to other parts of the country as a remedy for these problems. However, it's become invasive on the Pacific coast because it thrives so well in brackish - read salty-but-not-that-salty - water that it outcompetes the natives. Unlike most of the plants on the island that prefer fresh water, the cordgrass has a remarkable adaptation that allows it to extract the salt from the brine. It takes in the saltwater, compartmentalizes the salt molecules, and spits them out through pores on its leaves.
An assortment of critters use the grass both for food and shelter, including alligators (I can't wait to write about those guys), marsh raccoons, fiddler crabs, snails, algae, grasshoppers, and even wild horses. St. Catherines does not harbor wild horses, although our neigh-bor several islands south does. The periwinkle snail uses S. alterniflora to farm the fungus it eats. The aforementioned oysters wouldn't be here without the marshgrass. As it decomposes, creating its wonderful stink, it releases nutrients into the water. Shrimp, plankton, clams, and tiny fish use the nutrients and they in turn feed the bigger animals here. Despite not being a fish eater myself, I can appreciate that the oyster and shrimp industries provide a lot of jobs in the area. There are a lot of fish-eating birds who rely on the marsh as a place to nest and feed and a lot of bird-watching folks who rely on the birds. In fact, while I was out taking photos for this article, I saw one of my favorite birds - the red winged blackbird - balancing effortlessly on a stem.
As Georgia DNR puts it:
"Georgia's coastal marshlands encompass approximately 378,000 acres in a four to six mile wide band behind the barrier islands. Thriving in the waters of the estuaries, these marshes have been identified as one of the most extensive and productive marshland systems in the United States. It is production almost beyond comprehension, producing nearly twenty tons to the acre; it is four times more productive than the most carefully cultivated corn. Georgia's salt marshes produce more food energy than any estuarine zone on the eastern seaboard."
So, when I step out of the intern house on the odd morning and gag on the enveloping stench wafting in from the west, I try and remind myself that I'm glad the marsh is there. Its undulating patterns of emerald, ruby, and peridot makes for lovely photos, even if I have to plug my nose to take them.