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The orca wars escalate, with special reference to the economics of fisheries

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The orcas will wait all day for a fisher to accumulate a catch of halibut, and then deftly rob them blind. They will relentlessly stalk individual fishing boats, sometimes forcing them back into port.

Most chilling of all, this is new: After decades of relatively peaceful coexistence with cod and halibut fishers off the coast of Alaska, the region’s orcas appear to be turning on them in greater numbers.

“We’ve been chased out of the Bering Sea,” said Paul Clampitt, Washington State-based co-owner of the F/V Augustine.

Like many boats, the Augustine has tried electronic noisemakers to ward off the animals, but the orcas simply got used to them.

“It became a dinner bell,” said Clampitt.

John McHenry, owner of the F/V Seymour, described orca pods near Alaska’s Aleutian Islands as being like a “motorcycle gang.”

“You’d see two of them show up, and that’s the end of the trip. Pretty soon all 40 of them would be around you,” he said.

A report this week in the Alaska Dispatch News outlined instances of aggressive orcas harassing boats relentlessly — even refusing to leave after a desperate skipper cut the engine and drifted silently for 18 hours.

These are not Coasean orcas, or are they?  And sperm whales are now in on the act:

Fishing lines are also being pillaged by sperm whales, the large square-headed whale best known as the white whale in Moby Dick.

“Since 1997, reports of depredation have increased dramatically,” noted a report by the Southeast Alaska Sperm Whale Avoidance Project.

A remarkable 2006 video by the Avoidance Project captured one of the 50,000 kg whales delicately shaking fish loose from a line. After a particularly heavy assault by sperm whales, fishers are known to pull up lines in which up to 90 per cent of the catch has disappeared or been mangled.

Here is the full story, with video, and further points of interest.  For the pointer I thank the excellent Mark Thorson.

The post The orca wars escalate, with special reference to the economics of fisheries appeared first on Marginal REVOLUTION.

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denubis
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freeAgent
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Hmmm
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How I really feel when I hear someone say that images should be...

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How I really feel when I hear someone say that images should be stored in the database.

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denubis
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Schlock Mercenary: June 22, 2017

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denubis
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A Critical Problem

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This photo gives me the creeps.

When you work with dangerous stuff, you have to condition yourself to respond at the level of emotion. You have to think things out too, but having a sense of what you can and can’t do that operates immediately is important. Children learn that hot stoves and automobile traffic are dangerous. We automatically stop at the street. It’s tourist season in Santa Fe, though, and I have observed that some lack that automatic response.

I’ve dealt with dangerous stuff since I was a child. I had a real chemistry set, not the baking-powder-and-vinegar wimp boxes that are the only things sold now. My parents walked with me a lot in the outdoors and made it clear that wild strawberries were good to eat and deadly nightshade was not.

I loved my lab courses in high school and college. Working at a national laboratory added more precautions I needed to learn. I worked with high-voltage lasers. I did a little bit of plutonium chemistry in a glovebox. And then I managed people who were developing cans for storing plutonium.

We expected the plutonium to be in the form of flat cylindrical ingots, like the enriched uranium in this photo. 400px-HEUraniumCIt had to be protected from the air, from unauthorized removal, and from criticality incidents. The criticality safety group played an important part in designing those cans. The cans were about a foot high. The ingots were about an inch thick. The extra space was for criticality safety.

Probably before I came to Los Alamos, I read about Louis Slotin and Harry Daghlian, who were killed by criticality incidents. They were doing experiments to determine criticality properties for nuclear weapons design. They died horribly. Don’t read about them unless you have a strong stomach.

The metal rods in the top photo are plutonium. Rods can roll. These rods could roll closer to each other and perhaps produce the kind of runaway neutron reaction that killed Slotin and Daghlian. Putting a hand in to separate them could make the reaction worse because the water in a human body reflects the neutrons.

I had formal safety training, informal discussions with more experienced people, and made it a point to internalize rules of thumb. Keep pieces of plutonium separate. Abide by glovebox limitations; every glovebox has a sign with the limits of plutonium allowed in it. For solutions, keep them dilute and in flat containers. Flat/thin is safer; the closer a shape is to spherical, the less material is needed to go critical. IIRC, there were racks to put rods in if you were working with that shape of metal, so that they didn’t accidentally roll together.

That photo is at the center of two articles from the Center for Public Integrity (NMPolitics.net, Washington Post). They are based on an investigation reported here. According to those articles, a technician ignored glovebox limits and arranged the plutonium to take that photo for management. A Los Alamos manager is also quoted in the articles as saying that the criticality safety group was an unnecessary expense. A number of the senior people in the criticality safety group were of my vintage and were expected to retire about when I did. According to the articles, management’s signal was heard loud and clear, and the rest left.

It took the criticality safety group two months to work out the criticality aspects of our can design. I found that frustrating, too. They had to consider the way the cans might be stacked, how they might fall together and how the ingots inside might move if a stack of cans fell. What if they were in a flooded area? If people decided to rescue them from that flooded area? Water, by itself and in human bodies, enhances the neutron reactions that lead to criticality.

The criticality safety group develops those criticality limits posted on gloveboxes. They take into account the kinds of operations in the glovebox, the equipment inside, and the effects of operators’ hands and bodies nearby.

I learned from people who recalled personally what happened to Slotin and Daghlian. Today’s managers at Los Alamos are rotated through, I’ve heard, every two years. There are not many other places where one learns criticality safety. If Los Alamos is to manufacture nuclear weapons pits, criticality safety evaluation is essential.

A criticality accident affects people who are close to it. It is not a nuclear explosion; the neutron reactions are the same but occur much more slowly. The closest people die horribly, but some tens of feet distance and walls between will shield others. Raemer Schrieber was present at the Slotin accident and lived into his eighties.

It is unconscionable not to educate workers to the dangers involved with handling plutonium. It is worse to encourage poor practice. Did the manager for whom that photo was made understand criticality safety? Or the manager who said to just keep working?

One of the reasons for adding industrial partners to the management of Los Alamos along with the University of California was to improve safety practices. That was done without considering the standard industrial management practice of rotating managers rapidly and the ever-present profit motive. Industry does things better, period. But perhaps not for a singular enterprise like designing and building nuclear weapons.

Coda: I am usually highly critical of articles on nuclear issues coming from the Center for Public Integrity. They often get the science wrong and display an excessive fear of radioactivity. They did a much better job with this investigation. There are a number of small errors and infelicities of word use in these articles, but nothing like the bloopers they have produced before.

Update: The National Nuclear Security Administration says that the issues of criticality safety have been cleared up.

This is plausible because the photo is said to have been made in 2011. That would allow time to reassert the importance of criticality safety and rebuild the group responsible for it. And, as I said above, the Center for Public Integrity has been sensationalistic in the past. But I’d like to hear more from NNSA. The fact that that incident occurred at all is disturbing.

Cross-posted to Balloon Juice.








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Ad Hoc (Daily Nous Philosophy Comics)

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Ad Hoc
by Rachel Katler



Other Daily Nous Comics / More Info about DN Comics / Rachel Katler on Twitter

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The post Ad Hoc (Daily Nous Philosophy Comics) appeared first on Daily Nous.

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When IntelliSense tries to help me by autocompleting all the...

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When IntelliSense tries to help me by autocompleting all the wrong stuff

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