Saturday, 21 March 2015

Antarctic krill: keystone species menaced by acidification and overfishing

Krill photo: Stephen Brookes
Nature Climate Change reported two years ago that krill were in danger from CO2 ocean acidification. The entire ecosystem could collapse within 200 years, says biologist Dr So Kawaguchi. It is already under stress from climate change: temperature rise, productivity change and ice melt. Another NCC article reported the dangers to other species. Vast areas of the ocean will become uninhabitable for reproduction of the krill, a keystone species on which whales, seals, penguins and seabirds depend. The British Antarctic Survey points to an 80% decline of krill since the 1970s, possibly due to loss of  food: algae under shrinking sea ice.

BioMarine's Krill Fishing and Processing Factory Ship Photo: Erwin Vermeulen / Sea Shepherd
Meanwhile another threat has emerged: industrial overfishing. Huge factory ships suck up tons of krill to turn them into "organic" fertilizeromega-3 pills and fishmeal for farmed fish. In effect, corporations are becoming the primary predator. Krill still constitute the largest biomass on the planet, outweighing the human population. In 2013, Sea Shepherd reported ships from Norway (shown), China, Korea, and Poland. Ironically, some  receive Marine Stewardship Council "sustainability" certification -- which leads to questions whether big conservation NGOs like WWF are greenwashing. 

Following the fishmeal trail raises more questions:  is this yet another case of factory farming, dangerous to ecosystems as well as human health? Sea Shepherd states: 
Fish farming has many well-documented problems: pollution of the fish farm locations, spreading of diseases and parasites to wild populations, higher contaminant levels than wild-caught fish... predators, like seals and sea lions [are] killed for being attracted to the fish farms and especially the wastefulness of catching fish (and in this case Krill), to feed other fish, to feed people...and dog food. Will there come a time when our pets consume more Krill than the world’s whales, like our factory farmed animals consume more fish than the world’s sharks?

Industrial competition for protein "is becoming more and more acute," Denzil Miller of the Commission for the Conservation of Antarctic Marine Living Resources told the New York Times. Though scientific estimates of the actual stock are still guesswork, NYT predicted the krill-killing industry, with new pumping and evaporator technology, could "jump from just more than 100,000 tons to several million tons" a year. Another fisheries collapse is in the making.

Further reading
Encyclopedia of Earth, the "Antarctica Large Marine System" (2012).
SOS Antarctic Krill, list of recent scientific studies. "Vacuuming the Antarctic for krill" (petition 2014).

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