Science in Society: Exploring Change in the Bayou

Science in Society: Exploring Change in the Bayou

Mississippi deltaSatellite images of the Southeastern Louisiana coast are mostly dark with green capillaries blossoming into lace strands that branch again and again into the surrounding blackness. Water is dark blue or black on satellite images because it absorbs most of the sunlight. The green is  ribbons of saltgrass separating narrow fingers of fresh water from a surrounding salt water.

The satellite images hint at the history of the land, its slow sinking, which used to be offset by the deposit of fresh silt from upstream.  That was before the Mississippi moved west, and left behind only narrow tendrils of river (the bayous) that don’t bring enough silt to offset the sinking.  In the last 100 years, this natural loss of land has been accelerated. The cypress trees, whose roots held the soil, have been logged always. Canals dug for oil cris-cross the bayou and grow from 3-food wide paths to broad avenues as they erode.  An with the introduction of the nutria, an invasive rat that consumes saltgrass, the shoreline's last line of defense is disappearing too. 

Before I went to the bayou, I imagined shoreline as a permanent and sharp division between ocean and land. In Louisiana the shore is a tentative, multi-pronged incursion of land into saltwater; but ultimately, when the river moves,  saltwater wins. Human activity aceelerates the lands loss. As the climate warms and sea level rises, Louisiana won’t be the only place were salt-water battles land.

Shrimp boat in bayouThe view from the back of Donald’s shrimp boat, spotlessly clean and swimming pool blue, slowly motoring down the bayou on an unseasonably warm day in January, is more encouraging. Donald and his wife Theresa are our hosts, and they are introdcuing our small group of scientists and students to the bayou. Both sides of the bayou are lined by fishing boats that have been parallel parked so that their sides are even with the bank  - only 2 feet above the water. Beyond the banks: a ten-foot wide strip of grass, a one-lane road, houses perched on a 16-foot high lattice of pressure-treated lumber, a larger stretch of land, and five-foot high ridge, the dike that separates the bayou from the marsh.  As we motor slowly, so as not to cause a wake in the narrow bayou, a few men are hosing down their open-air shacks for cleaning fish.

Ghost treesTheresa is in the back of the boat along with the rest of our group: we are coming to the bayou to see if our science can be of any use to Donald, Theresa and their neighbors.  Theresa tells us that the marsh behind the dike is changing to open water and certain vegetables don’t grow as well on this side of the dike anymore.  She points out the ghost trees, trunks and few large, blunt-ended branches - all that remain of the cypress trees that were once ubiquitous here. 

She has been to the United Nations to talk about the changes she’s seen, and she speaks to our small group of scientists with passion and ease. She is the shortest person on the boat and the obvious expert.  Her T-shirt shows a crying Indian woman, above the words “Columbus discovered America – I have my doubts.” Later, when Donald cuts the engine and comes out to tell us about the area, she’ll do a lot of his talking, occasionally offering him the opportunity to concur. He always does, adding a bit of detail, sometimes in French and always with a mumbled smile.

Most of their stories of change in the bayou don’t match the beauty of the place. Donald and Theresa tell of families leaving, oysters dying, shrimp that are too sickly to eat, oil-spill cleanup in the middle of the night.  The stories are told with shrugs and the words often trail off. It is a litany of change, but the changes are less important than the will to remain.

The scientists ask questions and construct theories and scenarios about the scientific basis underlying the stories that Donald and Theresa share. Eager to understand and explain, our group even interrupts Donald or Theresa on occasion. They are patient, though, and refocus the conversation on the knowledge that comes from living locally. 

For those of us scientitists who are guests in that blue boat, the goal of this expedition is to understand the bayou landscape and the changes from the point of view of the people who live there, and, hopefully, add our scientific approaches to the set of strategies they are already using to adapt.  If we are successful, some of the students on the trip will spend the summer working in the bayou, side-by-side residents like Donald and Theresa, and supported by more scientists back home in Boulder, Colorado.

My own hope for this trip is to see if the college science students are interested, if the our research is relevant to this place, and, most importantly, if the local community is interested in working with us.

After the conversation from the back of the boat, we motor faster on a wider strip of water. Three dolphins jump in the boat’s wake.  Theresa has already cooked a dinner of shrimp, salad, rice and pork, and two king-cakes. We eat and she gets ready for a church function.  Our group leaves a little awkwardly. No one is quite sure how to properly say thanks for the intimate glimpse inside their lives and livelihood. While we want a next step, one isn’t readily apparent.

I worry, while driving the van back to New Orleans, about what I might be doing to these students.   It seems like a fool's errand to send them into a community equipped with only atmospheric science. How can our narrow expertise in weather and climate be any match for this complex struggle between land and sea?  Maybe the whole idea of building a research project around community needs is suspect. Can the complexity of the real world be translated into the ordered thinking of the laboratory?  Maybe it was only my hubris that brought us all here, and our science isn’t equal to the challenges this community faces.

Only later does it occur to me that science doesn’t need to be equal to the challenge.  Small steps matter.  In the same way that scientists have always worked one small experiment at a time, accumulating facts and data until a tipping point is reached and the tiny pieces come together in a new understanding, this community is partnering with any number of scientists from any number of disciplines, slowly adding up the pieces into a strategy that works. We aren’t the first scientists, we won’t be the last, but we seem to be welcome.  Perhaps there is no one unwelcome when it comes to this ongoing struggle between land and sea.