Louisiana’s crab bans spurred by changes in climate and habitat
27th February 2017 · 0 Comments
By Susan Buchanan
South Louisiana’s blue crab population is on the decline, pummeled by environmental and man-made threats. Increased trapping, less rainfall, no recent hurricanes, wetlands loss, predators, oil spills, closing of the Mississippi River-Gulf Outlet Canal and river-water diversions have taken their tolls. In response, Louisiana’s Wildlife and Fisheries Commission last summer decided to ban crabbing and trap use for thirty days, starting on February 20 of this year.
Over these thirty days, traps must be removed from state waters, including Louisiana’s three-mile territorial seas. Meanwhile, a longer-term restriction on harvesting of immature, female blue crabs began on January 1.
Louisiana harvests about 45 million pounds of blue crabs annually and hauls in more than that in a post-hurricane year, according to the state’s Department of Wildlife and Fisheries. Landings are compiled from trip tickets submitted by commercial fishermen and seafood dealers. Since these tickets were introduced in 1999, landings reached a peak of 54.9 million pounds in 2009, the year after Hurricanes Gustav and Ike. They’ve fallen since then. Louisiana provides a quarter of the nation’s blue crab catch.
“This 30-day ban means you won’t have live, boiled crab to eat for awhile,” Julie Lively, associate professor and fisheries specialist at Louisiana State University AgCenter, said last week. Frozen meat from local crabs caught before the ban and product from neighboring Gulf states will keep restaurants and grocery stores supplied, however. And, though it’s sometimes shunned in Louisiana, imported crab meat from Asia—primarily Indonesia—and from South America is another option.
Because traps catch more crabs faster and with less manpower than nets or trot lines, their usage has grown since the 1960s. Today most of the state’s commercially sold crabs are caught in traps, according to LDWF. Increased use of traps has contributed to excessive fishing. And trappers inadvertently capture immature crabs, preventing their development.
As for other factors hurting blue crabs, Lively and experts at LDWF aren’t entirely sure which of them are the biggest culprits. But something had to be done to support the population.
“The state can’t control weather or wetlands loss, but it can use the management tool of limiting the harvest,” Lively said. The 30-day ban was set for late February to late March because blue crabs are small then, before they reach full size in July and August.
“We’ve had drier years recently, and that’s correlated with declines in crab population,” Lively said. “We don’t want hurricanes and haven’t had a big one since Gustav in 2008, but crab numbers do increase after a storm.” During hurricanes, baby crabs are pushed into bays where they’re protected from Gulf predators. In Lake Pontchartrain, the state’s second-largest, blue-crab habitat after Terrebonne Basin, landings reached a recent high in 2009.
Crabs inhabit the state’s estuarine basins—Terrebonne, Lake Pontchartrain, Barataria, and the Atchafalaya-Vermilion-Teche Rivers.
Conditions in Lake Pontchartrain have changed, however, since the MR-GO shipping lane was shut in late 2009 to prevent storm surge. The lake’s water is fresher or less saline now, Lively said. Crabs harvested there aren’t as large and plentiful as they once were.
And statewide, adult blue crabs were more abundant back in 1970 than they are now, according to the Audubon Nature Institute last year.
As local temperatures and sea levels rise, south Louisiana is losing wetland estuaries that nourish and protect young crabs. In 2010, BP oil spilled off the coast of Plaquemines Parish soiled wetlands.
Studies about the spill’s impact on blue crabs are inconclusive, however, Lively said. “
The state’s diversions of Mississippi River water to fend off oil from the BP spill, and separately as a way to rebuild wetlands, have pushed crab larvae and babies into the sea where predators loom, Lively said.
At this point, it’s unclear which factors are most to blame for a decline in the state’s blue crabs, Jeffrey Marx, LDWF marine biologist and crab program manager, said last week. Less rainfall and ongoing predation on crabs are negatives, he noted. Predators include red and black drum, sea catfish, sheepshead and spotted sea trout.
Asian tiger prawns, an invasive species, may be a threat to Louisiana’s blue crabs, LDWF noted in a 2014 study.
Commercial crabbers set plenty of traps in their work. In a now-dated, LDWF study from ten years ago, a Louisiana crabber’s trip averaged 7.2 hours, and an average 319 traps were laid. Traps soaked in water for an average 63.5 hours. An average 1.34 crabs were caught in each trap. Landings per trip ranged from 340 pounds in Terrebonne basin to 717 pounds in the Mississippi River basin.
Meanwhile, the state is trying to protect undersized blue crabs from fishermen. For now, crab traps must have at least two escape rings of 2-5/16 inches or more in diameter. An exemption for traps set in Lake Pontchartrain ends in mid-November. And starting then, at least three escape rings, including two in a trap’s upper chamber, of 2-3/8 inches or more will be required on traps in all crabbing areas.
The state’s ban on commercial harvesting of immature, female blue crabs, excluding those headed for processing as softshell, began on January 1 and extends through 2019. Immature females, known as maidens, are distinguished by triangular aprons on their abdomens. Grown female crabs have dome-shaped aprons.
During the current, 30-day ban, LDWF is removing crab traps from the water. Similar bans will be imposed in 2018 and 2019, starting on the third Monday in February of both years. “Violating the 30-day trap closure could result in a ‘taking crabs during a closed season’ citation,’ with penalties ranging from a $100 to $350 fine and up to 60 days in jail per offense,” LDWF spokesman Rene LeBreton said last week. And someone caught taking immature, female crabs can be slapped with a fine of $100 to $350 and up to 60 days in jail.
In the water, conflicts occur between the state’s crabbers and shrimpers. Crab traps are sometimes damaged by shrimping activities, and shrimpers are hurt by crab traps caught in their gear. Louisiana’s Blue Crab and Shrimp Task Forces address these inter-industry concerns.
Frozen, blue-crab meat was available last week at the open-air, Westwego market known as the Shrimp Lot in Jefferson Parish. “Because this 30-day ban was coming, we bought lots of fresh, local crab from January 30 to February 16, and froze it right here,” Chad Encalade at Amy’s Seafood said last week.
“People want fresh, but they have to take what can get,” Encalade said. “Our frozen’s selling okay but not quite as well as I expected.” Last week, Amy’s frozen crab was priced at $18 a pound. Before the 30-day ban, the vendor’s fresh, local crabs fetched $21 a pound.
This article originally published in the February 27, 2017 print edition of The Louisiana Weekly newspaper.