Thursday, August 5, 2010

Red Lobster Faring Just Fine in the Post-Spill World



It remains unclear exactly how much damage BP's oil spill will do to the aquatic life in the Gulf of Mexico, but if you're worried about one of the worst environmental disasters in decades cutting into your $11.99 "festival of shrimp," you can rest easy. It turns out some of the country's most popular seafood restaurants have placed more emphasis on the second syllable of "seafood" rather than the first.

According to Rich Jeffers, a spokesman for Red Lobster, the casual-dining seafood chain gets very little of its shrimp from the gulf—or any ocean for that matter. Instead, it grows "farm-raised" shrimp in ponds throughout South America and Asia (Jeffers mentioned Thailand specifically), and at any given moment, the company has enough shrimp to meet the demand of all 700-plus of its locations worldwide for at least six months.

Of course, maintaining such a large shrimp supply isn't easy. In order to keep so many crustaceans alive in the densely populated farms—there can be up to 170,000 shrimp larvae in a single pond an acre wide and a couple meters deep—antibiotics are pumped into the water. Environmentalists have decried such practices, arguing that they can be harmful to the local ecosystems, but Jeffers says all their farms are closely inspected and certified by the Aquaculture Certification Council.

"What I would point out to you is the benefit of seafood sustainability," he says. "We're able to provide shrimp year-round, not relying on harvesting them from the ocean, which can only meet a certain demand."

Long John Silver's, the national fast-food chain, was not so forthcoming about the source of its shrimp, but it did tell NEWSWEEK in a short e-mail that is "not affected" by the oil spill.

So breathe a sigh of relief, cheap-fish lovers! Just as there is no end in sight to the consequences for the gulf, your endless shrimp platters will indeed remain endless.

A circulation model to investigate the movement of wastes from an Open ocean aquaculture site



David W. Fredriksson*, James D. Irish, Dale A. Kiefer, Jack Rensel, and Frank OBrien

Department of Naval Architecture and Ocean Engineering,
United States Naval Academy
590 Holloway Road 11D, Annapolis, MD 21402
USA
fredriks@usna.edu A numerical circulation study of the western Gulf of Maine was conducted to investigate the movement of wastes from an open ocean aquaculture site. To examine the hydrodynamics of the region, a domain was built with the ADvance CIRCulation model with Gulf of Maine bathymetry, shoreline, island and open ocean boundary conditions. At the open boundaries, the model was forced with dominant tidal elevation components, including the M2, S2, N2, K1, O1 constituents, representing possible low flow conditions. These conditions are with no weather forced or geostrophic currents to further diffuse and advect material from the site, but just the regular tidal motions. Model predictions were compared with surface elevation and Acoustic Doppler Current Profiler (ADCP) measurements from a moored instrumentation platform at the aquaculture site. At the site, the ADCP collected velocity data sets oriented in the east-west, north-south and vertical directions at nineteen, 2 meter depth bins. The data sets were processed to obtain the velocity tidal components and reconstructed to form a time series. The reconstructed time series was then compared with the model results. Differences between the model and measured results were on the order of cm s-1

The numerical flow values from the large model domain were then used as input to the program AquaModel. AquaModel is a GIS tool that provides three-dimensional simulation of growth and metabolic activity of penned fish as well as the associated flow and transformation of nutrients, oxygen and particulate wastes in adjacent waters and sediments. AquaModel can be used to examine both the near and far field affects of individual or clusters of fish cages. The information can then be used to effectively site new farms, evaluate operation techniques, and plan monitoring programs.