Approximately
50 acres of the Hackberry Bay Public Oyster Seed Reservation
in Lafourche and Jefferson Parishes were recently rehabilitated
by the Louisiana Department of Wildlife and Fisheries (LDWF)
Marine Fisheries Division as part of a federally-funded oyster
ground rehabilitation effort.
The process involved
placing cultch material (limestone, crushed concrete, oyster
shell) on the water bottoms to provide a suitable substrate
for larval oyster attachment. This effort is the latest in
a long line of oyster reef building/rehabilitation projects
(also known as cultch planting) performed by LDWF in various
years dating back to the early 1900s. Including this project,
LDWF has placed over 1.5 million cubic yards of cultch material
on nearly 30,000 acres of water bottoms within Louisiana’s
public oyster areas since 1917.
The Hackberry Bay
oyster rehabilitation project took place from May 20 to May
25, 2008. A total of 10,000 cubic yards of cultch material
were placed with approximately 75 percent consisting of size
#57 limestone rock (approximately 1.5 inches across widest
diameter), approximately 15 percent consisting of crushed
concrete, and approximately 10 percent clean oyster shells.
The contractor
utilized high-pressure water spray and a clam bucket to spread
a thin layer of cultch material on water bottoms. This project
is expected to result in harvestable quantities of marketable
size oysters (3 inches) within 24 months post-project. Similar
projects in past years have yielded benefit-cost ratios from
2:1 to as much as 20:1.
The project was
funded through a congressional appropriation of federal hurricane-related
fisheries disaster monies for oyster ground rehabilitation
and was part of $53 million in fisheries resource recovery
funds passed to LDWF by the National Oceanic and Atmospheric
Administration (NOAA) through the Gulf States Marine Fisheries
Commission (GSMFC).
