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Is the fishing industry leaving enough food for Antarctica’s top predators?
ScienceMag.org ^ | Jan. 15, 2019 | Erik Stokstad

Posted on 01/16/2019 3:02:39 PM PST by ETL

Krill, crustaceans smaller than a cigarette, play an outsize role in the ecology of the ocean around Antarctica: Penguins, whales, and other predators feast on vast swarms of the shrimplike animals.
Now, researchers have launched a broad international survey of krill’s main habitat in the Scotia Sea—the first in nearly 20 years—to learn whether a growing fishing industry is leaving enough for krill’s natural predators.

The effort, led by the Institute of Marine Research (IMR) in Bergen, Norway, began in earnest last week when Norway’s new polar research vessel Kronprins Haakon sailed from Punta Arenas, Chile, for the Scotia Sea. It and five other vessels will spend nearly 2 months mapping krill abundance across an area about the size of Mexico. Beside gauging population, the project will test tools for cheaper, more frequent surveys that could improve oversight of the fishery. “With a more dynamic management system, we can be more certain that the fishery is not negatively affecting the krill populations or the predators,” says Bjørn Krafft, a marine biologist at IMR who is directing the $5 million Norwegian cruise.

Soviet vessels were the first to ply the Southern Ocean for krill, which was ground into fish meal. By the 1980s, scientists began to worry about the effect on krill-feeding predators. The Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR), a treaty organization established in 1982, set tight limits on fishing, now at 620,000 tons per year. Most fishing stopped after the 1991 collapse of the Soviet Union, but it has been slowly growing again. Norway takes about half the current catch, extracting omega-3 fatty acids for nutritional supplements. “We absolutely need to know whether the catch limit is still precautionary,” says Simeon Hill, an ecologist with the British Antarctic Survey in Cambridge, who is not involved in the project.

CCAMLR organized the previous large krill survey, in 2000. The central finding—about 60 million tons of krill in the Scotia Sea—reassured managers that they had been adequately conservative. But much smaller surveys, conducted annually in a few places, have shown that regional krill populations go through boom and bust cycles, making it harder to gauge the health of the overall stock from a single survey. “We have pieces, but we are missing the big picture,” says marine biologist Rodolfo Werner, an adviser to the Pew Charitable Trusts and the Antarctic and Southern Ocean Coalition, who is based in Bariloche, Argentina.

Casting a wide net

To estimate abundance of krill, a keystone species, six ships will use echosounders and focus sampling around fishing hot spots.

During the survey, vessels will retrace the previous transects, measuring krill swarms with echosounders, a kind of sonar, and confirming the identification with sampling trawls. Some ships will measure oceanographic variables as well, such as temperature, currents, and plankton, to see whether they can be used to predict krill abundance.

IMR will also test remote devices that could gather krill data continuously and more cheaply. The Haakon will deploy moored sensors, as well as wave gliders and a sail-propelled buoy, in order to compare their readings with the net and echosounder data. “This is one of the most beneficial parts of the survey,” says Bettina Meyer, a krill ecophysiologist at the Alfred Wegener Institute in Bremerhaven, Germany.

At the same time, land-based teams from IMR and the Norwegian Polar Institute will track seals, whales, and penguins foraging for krill in the Bransfield Strait, an important feeding ground near the Antarctic Peninsula. Matching their feeding behavior with survey results “has big potential to get a better idea of the interactions between the krill fisheries and the predators,” says So Kawaguchi, a marine ecologist with the Australian Antarctic Division in Kingston.

The survey itself won’t be able to reveal how the overall krill population in the Scotia Sea might have changed since the 2000 survey, given the variability of krill populations over space and time. Finding out what drives population changes will require more research on the seasonal movement of krill, for example, and the impact of climate change. Loss of sea ice, which protects young krill from predators, is expected to reduce their abundance, and rising water temperatures and acidification could also pose serious threats—ones that even the best management plan might not avert. 


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To: ETL

21 posted on 01/16/2019 5:11:59 PM PST by RightGeek (FUBO and the donkey you rode in on)
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To: ETL; All

.
EARTH TO COOL DOWN WARNS GEO SCIENTIST

Scientific reports from Canada and Greenland has indicated that the the shrinking arctic ice sheets have begun to replace themselves rapidly. Strongly suggesting the earth instead of warming, is beginning to cool down. It is still not known (or proven) if this is the result because of the reduced rate of sun spot activity.

Canadian geo scientist Professor R. Timothy Patterson of Carelton University is urging a go-slow on the rush for governments to “Play God” with global warming legislative blaming this on CO2 (carbon dioxide) discharges. Legislating corrections attempting to control a natural cyclic occurrence caused by; sun spots, the magnetic solar wind, and cyclic earth magnetic polarity reversal, among other natural occurrences including volcanism, meteors etc. Probably plays a very significant role in climate change. Yet ignorantly blaming man made CO2 emissions for climatic change. which is becoming a rapidly discredited and minuscule cause of global warming in his article published by Canada’s Financial Post. 6/20/07

Patterson was selected by the Canadian government to study the fluctuations in certain types of fish populations.
While doing so the Canadian Geo-Scientist found a correlation when certain species of fish had high population and then drastic drop offs. He discovered these fluctuations corresponded with sun spot activity and solar radiation vs cosmic activity. When earth cooling occurred.

Studying deep fjords along the Western Canadian coast where deep pools of low oxidation water exist. The Patterson study reached deep into the earths recent past of 4000 years of undisturbed sediments. Patterson found that when aquatic activity was highest and lowest in those collected sediments having high aquatic content had matched known solar protection when the magnetic wind was highest, and dropped off when earth magnetic fields activities were lowest.Thus causing cosmic radiation to intensify.

Then because the earth became unprotected by its magnetic fields from galactic cosmic activity. Patterson cites several accepted theories which concludes this then created cloud activity during such periods which increased drastically. Thus cooling earth and bringing in its ice ages.

In his presentation here is a professor urging more scientific study (like Pope Benedict)is needed. That politicians including Al Gore, of The Earth Is Flat Society, don’t know what the hell they’re talking about. Strongly suggesting that the global warming may be caused by exhaling politicos rather than serious scientific examination.

Patterson seems to be saying before Canadians start investing in palm trees they should be considering better parkas because what goes up must come down and the Mexicans better move over for a reverse population flow. The story was featured in The Drudge Report, and World Net Daily, which were linked in The US Mat’s last page. But lost due to source link changes .Posted this in my website 2007 http://www.theusmat.com/index.htm


22 posted on 01/16/2019 5:44:58 PM PST by mosesdapoet (mosesdapoet aka L,J,Keslin posting here for the record)
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To: mosesdapoet; All

I should have added that despite this occurring in the north pole what Patterson findings on solar activity seem to have a direct bearing on what’s going on in Antarctica. Let’s not also not forget that the magnetic poles are moving


23 posted on 01/16/2019 5:56:34 PM PST by mosesdapoet (mosesdapoet aka L,J,Keslin posting here for the record)
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To: mosesdapoet
Magnetic Poles


24 posted on 01/16/2019 6:00:31 PM PST by central_va (I won't be reconstructed and I do not give a damn)
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To: hinckley buzzard
Because we are the top predators.

I recognized that a millisecond after pressing submit.

25 posted on 01/17/2019 1:22:23 AM PST by fso301
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To: dragnet2

Ban drift nets.
They’ve destroyed more than one fishing region.


26 posted on 01/17/2019 1:24:21 AM PST by sparklite2 (Don't mind me. I'm just a contrarian.)
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