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" fertilizer, omega-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.
Someofus.org: "Vacuuming the Antarctic for krill" (petition 2014).

Ocean sinks failing - acidification crisis in N. America's shellfish industry

islandscallops.com

A collapse of West Coast scallop hatcheries is reported in Desmogblog (20 June 2014, excerpt): 

In 2013, 25 years of smooth sea scallop farming at Island Sea Scallops suddenly came to an end. Years of dealing with a 10 per cent mortality rate, suddenly hit 90 to 95 per cent,CEO Rob Saunders told DeSmog Canada from his office in Qualicum Beach, B.C.

Over 10 million scallops died from the 2010, 2011 and 2012 batches. It was an unprecedented die-off and Saunders attributes their deaths to an increasingly acidic ocean. Saunders’ tests reveal the pH balance of the water used in his nursery dropped from the average of 8.2 to 7.2.

Some uncertainty still remains as to the cause of the die-off, but scientists have shown the growing amount of carbon dioxide in the atmosphere is increasing the acidity of the oceans and inhibiting “the development and survival of larval shellfish.”

The Vancouver Aquarium’s records show the pH level in the Vancouver harbour has dropped from 8.1 in the 1970s to a low of 7.3 in 2001. And shellfish farmers up the Pacific Coast have been reporting massive die-offs for almost a decade.

“A lot of people criticize me, saying you can’t prove it and of course I can’t, but the correlation is pretty strong,” says Saunders.

Islands Scallops along with the federal Department of Fisheries and Oceans are undertaking a research project to determine the root cause of the massive scallop die off.

This year, Island Scallops introduced a new heartier species of scallop and quickened harvest rates, “because we don’t expect the animals to live for two years,” said Saunders. The pH level is up a bit to 7.6, but Saunders is still seeing a 40 to 50 per cent mortality rate.

“Am I feeling desperate – absolutely,” said Saunders “If you want to maintain a coastal industry, then we are going to need some help – we are going to need some help now, not two years from now.”

The Boston Globe's title "Rising acid levels in oceans imperil region’s shellfish: changes from surge in carbon dioxide take toll" (7 Mar 2015) is somewhat misleading; the acid levels it reports in Maine rivers come from precipitation. But the "canary in the mine" role of hatcheries as a monitor is significant. The article also notes a "shellfish crash" in the Pacific Northwest. According to an (over-optimistic?) NOAA report, that crash was reversed. It doesn't say exactly how, but presumably the hatcheries dam off acid waters, or time the hatchling release.

None of this will help the poor and vulnerable of the world who cannot afford fancy tech fixes. For instance, the Seattle Times' Seachange: food for millions at risk (21 Dec 2014).