• The Mississippi: A Visual Biography by Quinta Scott

    "Great book and great blog - thanks for the first book I have seen that addresses the contemporary river, headwaters to gulf." Dan McGuiness, Audubon, St. Paul, Minnesota

    Click to order

  • Catagories

  • Archives

  • May 2010
    M T W T F S S
    « Apr   Jun »
  • Meta

  • Advertisements

The Louisiana Year

Bayou Petit Caillou at Sevin Canal

Three years ago this week, I was headed out to Timbalier Island in  a small work boat that belonged to LUMCON, Louisiana Universities Marine Consortium, and captained by Carl Sevin. Wendy Wilson Billiot and her youngest son, Seth, came along for the ride. When Terrebonne Bay got to choppy for the small boat, we turned back to Bayou Petit Caillou and continued on to Lake Boudreaux.

A long time ago, in the days when I took oral histories along Route 66, I learned that if I keep quiet, I might learn something. That morning Carl and Wendy taught me about the Louisiana Year and Carl told me his grandfather’s story.

In the early 1920s Dolephus Sevin, a commercial fisherman, dug a canal in order to go seine shrimp.  He broke through the Bayou Petit Caillou ridge and headed east. When he finished, his canal measured the width of his shovel, wide enough to float his boat across the marsh at high tide to small, closed-in pond.

At the end of the nineteenth century, Louisianans, like Dolephus Sevin, seined for shrimp. Crews in small skiffs played out the nets in a circle. The weighted edge of the net dragged the muddy bottom of a shallow bay or pond, herding shrimp into a wide pouch. Once filled, Sevin pulled the loaded net out of the pond, floated back to his house, unloaded, and started over.

The Louisiana year: The people who live along the Louisiana bayous and draw their livings from the Louisiana coast live by the seasons–brown shrimp in May; white shrimp in August; alligators in September; oysters from December to April; crabs all year long; otter, mink, nutria, and muskrats in the winter; waterfowl in the winter.

That way of life is threatened. In 2000 the price shimpers got for their catch plummeted to fifteen cents a pound as they competed with the import of farm-raised shrimp from Asia and Central America. Pollution fouled oyster beds. They were closed. Alligator harvesting required a permit and was limited to September. People for the Ethical Treatment of Animals put a crimp in the fur industry and ladies stopped buying fur coats. To rid the coast of nutria the State of Louisiana offered five dollars a seven-inch tail for a nutria kill, but it was no match for the value of the lost mink pelts.

Eighty years after Sevin dug his canal, it had eroded, widened, and deepened to three feet at high tide on its own. Anglers, both commercial and recreational, found the canal gave valuable access to the wetlands lying between Bayou Petit Caillou and Bayou Terrebonne, so much so that in 1995 they were able to halt a restoration project that would have plugged Sevin Canal and several others that connected the two bayous.[i]

The Deepwater Horizon oil slick has disrupted and further threatened the Louisiana Year. On April 29 the Louisiana Department of Wildlife and Fisheries opened the shrimp season early to the region between the mouth of the Mississippi at the east to Vermillion Basin on the west to allow Louisiana’s shrimpers to harvest winter white shrimp and some small brown shrimp. By May 3 the shrimpers had gathered the marketable white shrimp and only juvenile brown shrimp remained. The department closed the season.

East Cote Blanche Bay in the Vermillion Basin

Brown shrimp spawn offshore in very deep water in the spring and early summer. The larvae migrate to estuarial nurseries like East and West Cote Blanche Bays in the Vermillion Basin between January and June where they grow into juveniles, protected in the marshes, seagrasses, or mangroves with soft bottoms rich in decaying vegetation. They are not picky about their diets, feeding on detritus, chitin, parts of annelids and gastropods, fish parts, sponges, corals, algal filaments, and the stems and roots of vascular plants. Once they reach about two and a half inches they move to deeper, open water, and at three and a half to four and a half inches, they migrate to the gulf. Tides, lunar cycles, maturation, water temperature govern their migrations. Too much freshwater will hasten their retreat to deep salt water.

The number of shrimp that grow to adulthood depends on the size and water temperature of the estuarine marshes. The larger the marsh, the more shrimp survive. They like an optimum temperature of about seventy-seven degrees. Colder (forty degrees), they die; hotter (ninety degrees), they become stressed, and cannot tolerate too much salinity. Separate the marsh from the estuary by levees and populations decline. They live about a year. The shrimp served in your cocktail are about six months old.[i]

Finally, LaCoastPost has daily updates on the state of the Deepwater Horizon oil slick and what is happening in the Gulf of Mexico.

[i] Turner, R. Eugene, and Brody, Michael S., Habitat Suitability Index Models: Northern Gulf of Mexico Brown and White Shrimp, National Coastal Ecosystems Team, Division of Biological Services, Research and Development U.S. Fish and Wildlife Service,  Washington, D.C., September 1983, 1-11. http://www.nwrc.usgs.gov/wdb/pub/hsi/hsi-054.pdf#search=%22brown%20shrimp%20Gulf%20of%20Mexico%22.

[i] Conversation with Carl Sevin, grandson of Dolephus Sevin, May 2, 2007, LUMCON, Cocodrie, Louisiana; Carl Sevin, Personal Communication, June 5, 2007; Conversation with Carl Sevin and Wendy Wilson Billiot, Cocodrie, Louisiana, May 2, 2007;  Robbins, Rebecca, “Globalization’s catch: Shrimp industry threatens communities and ecosystems worldwide,” AR-News, November 3, 2003, http://lists.envirolink.org/pipermail/ar-news/Week-of-Mon-20031117/010900.html; Stewart, Richard, “Nutria bounty a boon for longtime trappers,” Free Republic, December 15, 2002, Louisiana Department of Natural Resources, “Lower Bayou LaCache Hoydrologic Restoration [DEAUTHORIZAED],” May 31, 2007, http://www.lacoast.gov/reports/managers.asp?projectNumber=TE%2D19.


One Response

  1. Very interesting. I was with a group last night that was trying to sort out the difference between white and brown shrimp. Now I can send them this link and impress them with your knowledge. Amazing, the complexity of the whole process.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: