Most krill is harvested for feeding fish in fish farms, such as salmon
The vast majority of krill harvested today (around 98 percent) is turned into meal for fish farming. Only about two percent is used for krill oil in dietary supplements.
Krill is rich in nutrients (they sustain huge whales, after all) and they contain the carotenoid and anti-oxidant astaxanthin. Astaxanthin is what gives farm-raised salmon its pinkish color. If it were not for krill meal, most of your store-bought salmon would yield a pale gray meat.
Thus when Whole Foods Markets removed krill oil supplements from its shelves because someone there was misinformed about krill oil's sustainability – that is, Antarctic krill's ability to reproduce in sufficient volume to allow for harvesting for human use – it made little sense Whole Foods Market banned krill oil supplements for human use but continued to sell farm-raised salmon, which is responsible for far more krill harvesting than are krill oil supplements. Even so, the amount of krill harvested by humans for any reason – human or other consumption – is only the tiniest fraction of krill in the Antarctic Ocean.
Krill oil is sustainable
There is a lot of misinformation and rumor on the Internet about this topic.
Often times, if someone has heard of krill oil at all, he might say “Isn’t that what whales eat?” followed by “Aren’t you taking the food out of the mouths of whales?” Whales do migrate to the Antarctic to feed on krill. It is their main source of protein and other nutrients, and they can consume up to seven tons a day, scientists estimate. However, there is more than enough krill to go around.
Krill is said to be the largest biomass in the world, which means there are more of them by far, weightwise, than any other species. Many millions of tons of krill swim in the Antarctic. The Antarctic Ocean is monitored very closely by some of the world’s top ecology scientists who advise CCAMLR, the Convention on the Conservation of Antarctic Marine Living Resources. This is a 25-nation treaty organization formed to protect the species in Antarctica, especially krill. They have set strict catch limits on krill that are meant to ensure the species remains viable for the future.
CCAMLR scientists have set the sustainable harvesting limit at about 4 million tons. However, just to be extra safe, they have set what they call a “trigger limit” at 620,000 tons, a precautionary limit which would trigger a halt in krill harvesting, especially in any one area.
The nine vessels that fish for krill now have scientific observers aboard who make sure that the limits are not exceeded in any way.
One of CCAMLR’s top scientists is Dr. Simeon Hill, a senior scientific officer of at the British Antarctic Survey (BAS) at Cambridge, England. BAS is one of the world's leading environmental research centers and is responsible for the UK's national scientific activities in Antarctica. Dr. Hill unequivocally told WellWise.org “I would argue that sustainability is a far greater issue in many other fisheries than in the krill fishery.”