Tuna products tend to be less energy-intensive than many aquaculture and livestock-derived sources of protein, but catching tuna uses more energy than fishing some other breeds, according to a report by the International Seafood Sustainability Foundation.
Data in Fuel Consumption and Greenhouse Gas Emissions from Global Tuna Fisheries: A Preliminary Assessment suggests that the global tuna fishing fleet used approximately 3 billion liters of fuel in 2009 and produced 9 million tons of carbon dioxide.
Of these boats, those using “purse seine” gear – a floating net that is closed with a drawstring – accounted for 64 percent of total boat landings but only 37 percent of total fuel use. Purse seine tuna vessels have a fuel use intensity of 368 liters per metric ton of fish caught.
In comparison, a 2008 study into the Norway lobster fleet found that fishing that species resulted in a FUI of 4,119 liters per ton. However, a 2010 study found that Atlantic herring from the northwest Atlantic used only 21 liters of fuel per ton of catch.
As such the ISSF said that tuna fisheries “cannot be considered the most or least energy-efficient of commercial fisheries, but appear to fall somewhere in the middle.”
In other sustainable seafood news, High Liner Foods, a North American seafood company, has announced progress towards its sustainability goals.
The company increased the amount of certified sustainable raw materials it purchases, both wild caught and aquaculture farm-raised, from 27 percent in 2010 to 52 percent at the end of 2011. High Liner has set a goal of sourcing 100 percent of its seafood from sustainable sources by the end of next year.
In December, an ABC affiliate reported that sustainability was driving a comeback in caviar consumption in the U.S.
Caviar derived from wild sturgeon is outlawed in the U.S. as the breed is on the endangered species list. But sturgeon farms, based mainly in and around San Francisco, are producing legal, domestically-made caviar, the station reported.