Crab Farming Abroad/At Home

While Callinectes sapidus has yet to be farmed, the past 10 years have seen an explosion of farming with other crab species in Asia, Australia, and to a lesser extent Europe. Asian crab farming is the furthest developed in size and scope as well as the metric tonnage of crabmeat produced each year. Asian farms run the gamut from low-tech, pond-based farming to hi-tech, submersible cage facilities (figure 22). In pond-based farming operations, crab juveniles are caught in local waters (typically mud flats, or mangroves), and transplanted into closely monitored pond systems for rearing to adulthood. A combination of semi tropical temperatures, cheap land and labor make pond rearing an incredibly economical farming operation for much of southwest Asia. Cage systems require a significant amount of capital investment, but they have proven that they are equally viable in producing a large biomass within a small area earning good profit.


Figure 22 – Different types of crab farming currently practiced in Asia. Author illustration.

CRAB FARMING AT HOME

Recently, an experiment conducted in Swansboro, North Carolina has given some hope to Midatlantic crab farming proponents. In the summer of 2008, NCSU professor Dr. David Eggleston partnered with scientists at the University of Maryland who supplied him with a stock of some 30,000 juvenile crabs. Dr. Eggleston mowed the lawn of his dormant 10 acre farm irrigation pond and filled it with North Carolina tap water (3 ppt salinity). Two months after Dr. Eggleston had introduced the juvenile crabs to the pond, they had grown from ¼ inch juveniles to six-inch adults, “larges” on the sizing chart.

Figure 23 - Size Chart. http://www.marylandbluecrabexpress.com/blue-crab-sizing-chart.html

With an attrition rate of 80%, Dr. Eggleston had roughly 6,000 mature crabs at the end of the summer—an $18,000 harvest. Assuming the rapid growth rate measured in Eggleston’s pond could be maintained for more than 1 season, a farmer could raise two to three crops per year. Eggleston is succinct: “There is tremendous economic potential.” Given Dr. Eggleston’s project as a model, it would seem that blue crab farming is an economically viable proposition. What is more, there is so very much regional interest in the fate of the Chesapeake Bay blue crab, that political and capital interests will no doubt align to make crab farming a viable form of agriculture in Maryland very soon.


Figure 24 – Dave Eggleston’s 10-Acre crab pond in Swansboro, NC. Author’s Visualization.

BLUE CRAB FARMING 17 BLUE CRAB FARMING 18
[18] The Scientist, Oct. 2008