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Is Only Krill Oil Sustainable?

Over one third (or 3.5 million tonnes) of fish stocks destined for fish oil supplements are ‘poorly managed’, a sustainability report of 24 fisheries has found. The report from NGO Sustainable Fisheries Partnership (SFP) rated 24 ‘reduction fisheries’ – stocks turned into fishmeal and fish oil – according to quality of management and status of the target stock using its public database of
fishery information, FishSource.

For many years I've been arguing that krill oil is far more sustainable than fish oil--providing evidence--and this is just another study that confirms it. In fact, this study went so far as to say the only fishery that received an "A" grade was an MSC-certified krill fishery, meaning the stocks were in ‘very good condition’.

Without going into the boring details of this study, it's important to separate fact from marketing BS. I know some highly respected fish oil brands that have gone on a very misleading anti-krill campaign, which in the end, only puts more negative pressure on fish oil stocks and fisheries, exacerbating the problem. To conclude this post, I'd lik to share with you a rebuttal I put together for the industry that exposes the lies put out by one particular brand, who I won't mention by name...


Dear Retail Partner and Consumers,

For almost a year now, a document disguised as a “Fact Sheet” has been circulating, spreading inaccurate statements about Antarctic krill and its environmental sustainability. In fact, this document is so full of false statements that it really calls into question the credibility and reputation of any brand publishing such biased marketing.

In coordination with various krill oil suppliers, I hope to set the record straight and reaffirm what global environmental organizations, like the World Wildlife Fund, have concluded: that krill is one of the world’s most sustainable sources of marine-based omega-3s.

Let’s dissect the statements in the “Fact Sheet” and see exactly how factual they actually are.

1.       “baleen whale rely on krill to about 50% of their body weight when they are breeding in the Antarctic.”

Human harvesting of krill has a negligible impact on the baleen whales’ food supply. The actual total catch by humans the 2010-2011 harvest season was 180,986 tonnes, or about 0.2% of the whales’ krill consumption.

Further, as whaling up until the 1970s caused the near extinction of baleen whales—krill’s primary predator—krill populations increased dramatically. Since the 1970s, whale populations have recovered, and due to the shear mass of krill they eat, krill populations have seen a corresponding decrease.

CCAMLR. Statistical Bulletin, Volume 24, 2002-2011. CCAMLR-SB/10/24

Trivelpiece WZ, Hinkea JT, Millera AK, Reissa CS, Trivelpiecea SG, Watters GM (2011). Variability in krill biomass links harvesting and climate warming to penguin population changes in Antarctica. PNAS. 108:7625-7628

2.       Results of a 2010 study tracking Adelie and Chinstrap penguin populations over 30 years show an alarming decline of over 50%.”

a)     Implying this is due to human harvesting of krill is a misrepresentation of the study referenced (TRIVELPIECE et al. 2011). First, this study concludes that climate change is the main driver behind variations in krill population, and thus penguin population. Second, penguin populations increased 5-fold from the 1930s to 1970s. This was primarily due to increasing krill population (due to declining whale populations, which was a result of human hunting). Any decline in krill (or penguin) population would seem precipitous if starting at this unnaturally high reference point brought about by human whaling.

b)      Another recent study provides contradictory evidence. Using satellite technology, the researchers revealed that emperor penguin numbers in Antarctica have recently doubled.

FRETWELL et al. 2012. An Emperor penguin population estimate: The First global, synoptic survey of species from space. PLoS ONE, April 2012, Volume 7, Issue 4, 11 pages, e33751

3.       “With krill at already depleted levels, human fishing will result in continued decreases that will ripple through the ecosystem.”

There was no reference to support this claim, simply because krill is not at depleted levels so there cannot be any reliable reference. On the other hand, many fish stocks are depleted. A study in 2011 concluded that: "…at present 28-33% of all [fish] stocks are overexploited and 7-13% of all stocks are collapsed." It’s extremely hypocritical for any company selling fish oil supplements to attack krill based on sustainability. This claim is even more absurd when you consider that based on 2008-2009 data, 99% of the krill catch went to the aquafeed industry (i.e. to feed farmed fish).

It is interesting to note here that the majority of fish oil companies primarily depend on small species of fish, which also play an ecological role equivalent to that of krill in the Antarctic as a “staple species.” Therefore, this argument can be easily redirected towards most—if not all—fish oil companies, which themselves endanger marine pelagic ecosystems.

BRANCH et al. 2011. Contrasting global trends in marine fishery status obtained from catches and from stock assessments. Conservation Biology, Volume 25, No. 4 : 777-786.

4.       “No population survey has ever been completed for krill. The last effort to assess the stocks of krill was in 2000—12 years ago.”

“Krill has declined in in the Antarctic by 38-80% over the last years and along with the animals that depend on if for survival.”

a)      In the referenced publication (ATKINSON et al. 2004), the authors could not have calculated or claimed that krill has declined by 38-80% had they not assessed the stock. Therefore, these two statements contradict themselves, further exposing the biased marketing masquerading as science. Furthermore, that study mostly refers to waters surrounding the Antarctic Peninsula, which is only a portion of the Antarctic continent, and typically not under the same climatic conditions as the rest of the continent.

b)      12 years ago? Two more recent publications, one by the same author from the 2004 study, reassessed the value of krill population in 2009 and another survey was published in 2005, which again reveals the inaccuracies.

ATKINSON A., V. SIEGEL, E.A. PAKHOMOV, M.J. JESSOPP & V. LOEB. 2009. A re-appraisal of the total biomass and annual production of Antarctic krill. Deep-Sea Research I 56: 727-740.

SIEGEL V. 2005. Distribution and population dynamics of Euphausia superba: summary of recent findings. Polar Biology 29: 1-22. (Most recent assessment based on all known smaller survey over the last decades)

5.       “…trawlers that can scoop up swarms entirely – millions of tonnes of krill in one pass.”

It is physically impossible to “scoop up millions of tonnes of krill in one pass.” Catch sizes are in the range of 10-20 tonnes. In fact, the size of last season’s entire catch (globally from all vessels) was 180,986 tonnes—nowhere near millions of tons, and certainly not from a single vessel in one pass.

*CCAMLR. Statistical Bulletin, Volume 24, 2002-2011. CCAMLR-SB/10/24

6.       “Krill – MSC certified? Only one vessel of one company, Aker BioMarine in the krill fishery has applied for and received Marine Stewardship Council certification. The krill fishery as a whole has not been certified and this one certification was strongly opposed by a member coalition of conservation groups and Antarctic Scientists for this reasons stated above.”

Krill oil from Neptune is certified by Friend of the Sea. Both of these organizations also certify sustainable fish, and therefore, an attack by any fish oil supplier on these organizations is an inadvertent attack on themselves.

Krill fishery is relatively new and will take time before all vessels are certified. The vessels that Neptune uses are currently undergoing a similar certification to that of Aker’s and certification will be achieved within the next couple months. Regardless, all krill fishery vessels are from the member countries of the CCAMLR and are subject to CCAMLR rules and regulations.

7.       “With the decrease in sea ice, the fishery can get to places never accessible before.”

There are only certain zones that are allowed for fishing according to CCAMLR regulations. Krill fishing must be done at least 30 km off shore. “Inshore” fishing is strictly forbidden by CCAMLR.

KLEVJER T.A..TARLING & FIELDING 2010. Swarm characteristics of Antarctic krill Euphausia superba relative to the proximity of land during summer in the Scotia Sea. Marne Ecology Progress Series MEPS volume 409 157-170.

8.       “With little understanding of how much krill there really is, being cautious to protect this valuable species is essential, trying to manage a fishery without a population survey and the various key factors that influence it is like driving with a blindfold.”

We agree that it’s crucial that all key factors need to be considered; however, in reality there is quite a bit of research regarding krill’s abundance (as discussed earlier) and it’s hardly “like driving blindfolded.” As mentioned previously, the Antarctic krill biomass harvest is under the management of the CCAMLR, an international organization of 26 countries. The CCAMLR Scientific Committee periodically evaluates the Antarctic krill population (including research publications) and promulgates rules to be enforced by the Commission’s member states.

9.       “A lack of sea ice means less krill, which means less of everything that relies on them.”

It is certainly not as simple as that. An ecosystem has many more complex dependencies and interactions. Krill is not the only staple species in the ecosystem and many small fish species are also considered staple species. Also, ecosystems evolve and predators tend to change or diversify their prey over time. For example, it’s interesting to note that penguins have only recently started feeding on krill. While it’s not known why this shift away from other small prey (mainly small Antarctic fish) has occurred, it could logically be due to krill’s relative abundance, or depleted fish stocks (or a combination of both).

10.    Dr. Graham Hosie has spent 20 years tracking plankton in the Antarctic –krill’s food- and is alarmed at the declines he is seeing in krill, which he blames on climate change and over fishing.”

This statement is false since there have never been any reliable reports of “overfishing of krill.” Any decline in krill population has typically been attributed to climate change, not overfishing.

So while it’s always easier to sell products by attacking the competition, I encourage all brands in the industry to rise above underhanded tactics and sell based on the merits of their own products. At the very least, all brands should avoid fabricating stories, intentionally misrepresenting results of studies. or taking results out of context to fit a deficient position in a debate.

Lee Know, ND

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Source: Reduction Fisheries: SFP Fisheries Sustainability Overview 2015


  1. Best response I have ever seen. Thank you! Will be sharing this info for sure.


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