The Minke whale and Antarctic Krill paradox.

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Rate It! Donovan. Senior Member

Login/Join Posted 02-11-09 07:12 AM

I just want to say thankyou first to Animal Planet for Whale Wars, and to Mod_Kelly for this very interesting forum. I have certainly learnt a lot posting here, and I have had a good time doing it. Lots of laughs. I have noticed a lot of people have posted interesting links to, but they are all very spread out. So would be great if we could get them in one sweet post. Some people come for the conversation, some for the sources and information! I am going to post some I think are cool, if you don't think they are.... please counter with your own links. I would love to read your point of view. I am going to add a few quotes to put the links in context, I hope it doesn't make it look epic and put people off. Posts: 662 | Location: Byron Bay Australia | Registered: 12-16-08

Donovan. Senior Member

Posted 02-11-09 07:41 AM

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You know.... if you say the Southern Minke is endangered, then perhaps you are right. If you say the Southern Minke is not endangered then perhaps you are right. The point is that we do not know if the population is crashing, stable or increasing. Most of the data seems to point towards a very dramatic decline. Unfortunately the scientists have been sidelined by the politicians . But the situation as it stands is that Southern Minke are Data deficient! Japanese whalers killing every whale they see is not going to improve this situation either. We need population trend data, not a butchers list of protected animals that have been served up in Japanese diners. If we look at the authority on endangered animals we find the Minkes future is far from sure. Here is a picture of Minke population estimates.


quote: Red List Category & Criteria: Data Deficient The data analyzed by standard methods suggest a reduction of approximately 60% between the 1978–91 period and the 1991–2004 period. However, alternative hypotheses to explain the apparent decline are still under investigation. If the decline is real, its extent and causes are currently unknown, and it may still be continuing. The corresponding population reduction thresholds (criterion A2) are 30% for Vulnerable and 50% for Endangered, measured over a 3-generation time window, which in this case is estimated to be approximately 66 years (22 years per generation). If the decline proves to be largely or mainly an artifact, or proves to have been transient in the light of analyses of more recent data, the species would qualify as Least Concern. If it were real, the species would qualify as Endangered. Pending resolution of the uncertainties relating to the apparent decline, however, the species is listed as Data Deficient (DD).

The IWC discussed this in 2007. The decline was specific to minke whales; estimates for other species (blue, fin, killer, humpback) increased over the period; an explanation for the decline would need to account for this.

I'd like to add that ~ comparing declines caused by harvest followed by recovery from harvest controls to declines from loss of habitat and climate warming are apples and oranges. I will try explain about whales surviving past threats being different to the future ones they face. While genetics has revealed a stable Minke population for the last million years or so, the threats that now face Minke are going to be the largest they have ever faced before. Both of these threats revolve around the krill . So.... lets talk krill! Here is a picture of a krill if you have not seen one up close! quote: While in the Antarctic, minke whales feed almost exclusively on krill, primarily Euphausia superba, but also E. crystallorophias (ice krill), E. frigida, and Thysanoessa macrura (Tamura and Konishi 2006). Observed densities of minkes are highest near the edge of the pack ice, but these whales also occur within the pack ice (Shimada and Kato 2006). It is not known whether Antarctic minke whales also feed to any significant extent while outside the Antarctic on their wintering grounds or migration routes. Best (1982) found a very low level of feeding, almost entirely on euphausiids, by Antarctic minke whales taken in winter off Durban, South Africa. Antarctic minke whales may themselves be an important prey for type-A killer whales Orcinus orca (Pitman and Ensor 2003).


Firstly the melting sea ice in Antarctica threatens to starve the krill ~ this is because the krill feed on the algae that grows on the underside of the sea ice. Here is a picture of krill feeding.

If that was not bad enough the CO2 threatens to disolve them, by making the ocean so acidic their shells cannot form properly

We are looking at the potential extinction of what may be the most common animal on earth Euphausia superba in a mere 50 years.

The last thing we should be doing is expanding the krill fisheries now. Pictures of where the krill fishery is and who catches what.

It needs to be kept in mind though that even with a stable QUOTA for krill catches....

If the krill decides to not play your game ... then the quota's really do need rethinking.

quote: Estimates in the 1960's of krill "freed up" by the removal of the Baleen whales suggested that a fishery of 150 million tonnes may now be possible, because of the so called "krill surplus" (Ichii)

Of course the exact opposite happened to the predictions and the krill instead crashed. This has led even the IWC to concede that whales do seem to play a large role in maintaining the high krill populations. With whale waste fertilizing krills food source. After all there were so many whales, and so MANY have been killed! Theres no doubt the absence of the great whales has impacted the food web. The question is how much? If CCAMLR stuffs this [URL=""]krill harvesting[/URL] up it will be kicking the entire food web in the guts! Here is a video of lots of animals eating krill. The Southern Sea could very well for all intensive purposes die. We need to keep a close eye on this situation. If it goes to hell it will impact on all of our lives. quote: "research has found that these amazing little critters are also allies in combating global warming. In daylight, they feed on phytoplankton near the ocean surface.


When darkness falls they sink down, sending waste - which includes large amounts of carbon dioxide from the Earth's atmosphere - toward the sea floor and thereby removing the equivalent annual carbon dioxide emissions of 35 million cars."

It is our duty to protect the Antarctic ecosystem . Just like with the fish, there is absolutely no way of knowing if they will ever recover from our destruction of most of their population. Recent history has shown that whalers cannot be trusted to not poach anything they can find. Sources 1, 2, 3, 4, 5, 6, quote: # ^ Angier, Natalie (1994-09-13). "DNA Tests Find Meat of Endangered Whales for Sale in Japan". New York Times. # ^ Hearst, David (1994-02-12). "Soviet Files Hid Systematic Slaughter of World Whale Herds". Gazette (Montreal). # ^ Williams, David (1994-02-23). "We Didn't Know About the Whale Slaughter". Agence Fr. Presse.

Just a quick bit about whales eating all the fish! quote: In a paper written for the IWC meeting, Dr Pauly argues that whales cannot be a significant cause of fisheries decline because in the past, numbers of both whales and fish were much higher than they are now. He also cites evidence assembled in the 1990s showing that only about 1% of the food eaten by any group of marine mammals was taken in areas home to important fisheries for human consumption. “Making whales into scapegoats serves only to benefit wealthy whaling nations while harming developing nations by distracting any debate on the real causes of the declines of their fisheries.�

source 1, source 2, source 3. Bonus links! High Seas Task Force. cetacean (whale and dolphin) scientists What they think about Japans "scientific research" Posts: 662 | Location: Byron Bay Australia | Registered: 12-16-08

WatsonIsaBigFatLiar Senior Member

Posted 02-11-09 08:12 AM

photobucket isn't a source Posts: 61 | Registered: 12-20-08

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Donovan. Senior Member

Posted 02-11-09 08:31 AM

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All the photobucket hosted images come from links on this page.

difficult to know what you mean but I imagine its this -> http://www.iucnredlist.org/documents/attach/2480_v1223422179.pdf Which is found on the official Minke status page http://www.iucnredlist.org/details/2480 at the base of the area about Minke population and titled For further information about this species, see 2480.pdf. In future perhaps try to post a link to challenge what you doubt in my post. As I said I am curious to read your sources to understand your opinion.

Posts: 662 | Location: Byron Bay Australia | Registered: 12-16-08

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