[Editor's note: Jude Isabella will file Hook items as she attends the American Association for the Advancement of Science annual meeting being held in Vancouver.]
Wonder no more what is the carbon footprint of a shrimp cocktail -- for every 551 grams of aquaculture shrimp produced, a ton of carbon is released into the atmosphere.
Boone Kauffman, an Oregon State University researcher, presented his analysis of the shrimp aquaculture industry for a symposium on Blue Carbon, Green Opportunities at the American Association for the Advancement of Science Annual Meeting in Vancouver today. Blue carbon is the carbon stored in mangroves, seagrasses, and tidal salt marshes and it's about to be unleashed as a tool to save coastal ecosystems around the world.
Kauffman focused on what happens when mangroves are cleared to make way for shrimp farms in Southeast Asia. Farming shrimp is one of the fastest growing forms of aquaculture in the world, increasing ninefold during the 1990s. Today, it accounts for a third of the shrimp produced globally.
What is the jumbo carbon footprint of a shrimp? If you and four friends go for dinner and drinks and each have a farmed-shrimp cocktail, that releases 990 kilograms of carbon into the atmosphere. That equals burning 424 litres of gasoline. And apparently, compared with the shrimp eaters, you can drive from Vancouver to New York City in a Prius and claim the moral high ground when it comes to calculating your carbon footprint.
Coastal ecosystems are widespread globally, though rapidly being lost. About two per cent of seagrass habitat is lost annually. In the last couple of decades that loss has been calculated as a total loss of 29 per cent. Total loss of salt marshes has been about 50 per cent of salt marshes, and 35 per cent of mangroves. Not only do these ecosystems provide habitat for 75 per cent of marine fish (at least in the tropics), but they are valuable as carbon sinks.
Following speakers talked about the use of Blue Carbon sinks as a tool to save the estuaries, bays, salt flats, and other areas that teem with locally adapted life above ground and contain a global problem below ground. While the public and policy makers might know places like the Fraser River estuary are valuable for biodiversity, water quality, flood control, and fisheries, when fretting about carbon containment, forests have gotten all the attention.
Yet coastal habitats like mangroves release more carbon when destroyed than a tropical rainforest converted to cattle pasture -- the release is estimated at about two times greater. The reason lies below ground. Over 80 per cent of a mangrove's entire ecosystem carbon stock could be stored below ground. And seagrass and salt marsh carbon sinks are thought to extend six metres below ground, Kauffman says.
By leveraging a forest's contributions to capturing carbon and reducing emissions, policymakers have improved management and conservation, and have increased the importance of forests globally. The result has been a growth of financial incentives to reduce greenhouse gas emissions from deforestation and degradation.
Organizations like Restoring America's Estuaries, Conservation International and others are rallying behind the The Blue Carbon Initiative to try and do the same for coastal carbon sinks. Blue carbon promises to be the buried treasure for communities trying to restore and save coastal ecosystem.
Jude Isabella writes about marine biology and sustainability for The Tyee and others.
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peetey
13 weeks ago
head scratch
I'm a little unsure about the size of the cocktail for fours footprint if it does not entail :) taking down a mangrove swamp. What if the shrimp farm is in an otherwise barren environ? I've always thought farmed shrimp were getting near lab meat and tofu for ethical eating. ( My apologies to crustacean posters)
snert
13 weeks ago
Ummmm
So what would the carbon footprint of a replacement food be. Methinks the numbers are being stacked for effect.
These practices will become more and more popular as the world population grows. People need food for some silly reason.
wiley
13 weeks ago
Yum Yum
Most shrimp farms in Asia function as profitable sewage lagoons for recycling the waste of a seriously overpopulated upland. No wonder they want to export the little buggers.
deweaver
13 weeks ago
Shrimp farming
Too bad their assumption that shrimp farming is using mangrove land hasn't been valid for decades. Mangrove land is very poor for shrimp farms because it is anaerobic and contains a lot of metal sulfide compounds. When converted to fish/shrimp farms, the surface of these soils becomes aerobic and the metal sulfides are converted micro-biologically into "acid mine drainage", which harms the shrimp. Shrimp farmers found this out decades ago and quit using mangrove land out of self interest.
The preferred sites are some of the saltflats behind the mangroves where the soils are aerobic, low carbon and low in metal sulfides and above most high tides (for drain harvesting). These areas that only get flooded with saltwater on high high tides, which prevents agricultural usage or carbon buildup in the soils.
However, keeping shrimp pond bottom soils aerobic is difficult and a major problem area and I expect that most farms experience an increase in soil carbon over time. Farmers often have to dry and plow the bottom to slow the carbon buildup.
I didn't attend the AAAS meetings this time, but the authors probably didn't have any real shrimp farm knowledge or data, just old myths pushed by environmental activists combined with good data on mangrove carbon to produce misleading politically correct results. I guess this is what happens when a scientist moves out of his area of knowledge and into politics.
Van Isle
13 weeks ago
Shrimp, lobsters, prawns,
Shrimp, lobsters, prawns, crabs are all bottom feeders; it's now a term used on some human beings.
BarbaraAnn
13 weeks ago
Farmed Shrimp
It was about 10 years ago that my husband and I stopped on the highway at the sign " 100 Large Shrimp: $10.00. I asked my husband to check where they were from, of course he did not , they came from South East Asia, I will not eat any fish food from there, the water they are grown in is usually Stagnant. I want fresh West Coast real Fish not any thing farmed ever.
EWe threw out the bag of Shrimp.