LDWF to Construct New Oyster Reef in Calcasieu Lake


oysters spilling out of a sack

The Louisiana Department of Wildlife and Fisheries (LDWF) will construct a new oyster reef in Calcasieu Lake soon for the purposes of increasing oyster habitat and fisheries production. The construction process, known as cultch planting, is a proven habitat improvement technique in use by LDWF since 1917.

The project will consist of spreading approximately 12,500 cubic yards of crushed limestone on the lake bottom to create approximately 100 acres of artificial oyster reef near Long Point on the east side of Calcasieu Lake. Project construction is tentatively set to begin construction Nov. 27 and should be completed in approximately two weeks.

The contractor, Quality First Marine, will utilize high-pressure water cannons to spray the cultch material (crushed limestone) off the barges and into the water. Boaters should use caution while the operations are underway to avoid potentially dangerous flying cultch material. Light-loaded barges will ferry the material from a staging area in the Calcasieu ship channel near 9-mile cut to the project site to avoid excessive disturbance to the lake bottom while in transit.

The cultch planting method involves spreading clean cultch materials on the bottom of the lake as a base for small oyster larvae to settle.  Oyster cultch can include any hard, clean material, but LDWF traditionally uses old oyster shells, crushed concrete, or crushed limestone.  Cultch plants have been successfully utilized to establish or enhance oyster reefs state-wide, including Calcasieu Lake, as well as for mitigation for damages incurred to the Calcasieu Lake public oyster area.

LDWF has overseen the construction of several cultch plants within the area.  The earliest documented artificial reefs constructed in Calcasieu Lake go back to 1963 and 1969.  Respectively, these artificial reefs were 59 and 24 acres in size; oyster shell was the material used in the creation of the 1963 reef, while clam shell was used to construct the 1969 reef near Commissary Point.

Since 2007, there have been several small cultch plants constructed in Calcasieu Lake.  The most recent cultch plants constructed consisted of three reefs in 2015.  Two of the three 2015 cultch plants constructed in Calcasieu Lake were designed to serve as commercially harvestable reefs, while one was constructed outside of the harvest area.

One reef was constructed in West Cove and was the largest of the three reefs (25 acres).  Another reef was constructed in the southern end of the east side of Calcasieu Lake and was 20 acres in size.  The artificial reef located just north of the harvest area totaled 18 acres.  All three reefs were constructed using crushed limestone.

Other efforts utilized by LDWF to enhance oyster populations in the lake have consisted of deploying hatchery reared oysters (over 788 million larvae from 2012 through 2015 and over 34 million oyster spat in 2013), increasing the amount of biological sampling of the resource, reducing daily sack limits, reducing season lengths as well as total closures of some areas to harvest.  Additionally, the Louisiana Legislature recently restricted the method of harvest to hand tongs only.

The Louisiana Department of Wildlife and Fisheries is charged with managing and protecting Louisiana’s abundant natural resources. For more information, visit us at www.wlf.la.gov. To receive LDWF email alerts, signup at http://www.wlf.la.gov/signup.