Death on the Steppes: Mystery Disease Kills Saigas | Hacker News Reader

Death on the Steppes: Mystery Disease Kills Saigas

nytimes.com

38 pointsigonvalue11 comments

And there is a perfectly reasonable explanation for the sudden death of 10.000 herbivorous mammals that nobody seems to see: Chernobyl fire forests in 30-april-2015 releasing clouds of radioactive dust only 10 days before this event. Dust travelling by air normally settle down after a raining episode.

Animals died in few hours with synthoms totally compatible with radioactive poisoning in the chain food. Strange inmunosupresion, diarrhoea, pain in the mouths and guts and problems with breathing. Saigas are animals with a interesting nose that filters dust and those tissues are connect with a net of blood capillaires so poisoning by dust could be quicker in this species.

If someone here have friends or know some scientists working in Kazakhstan, please warn them that have extra care with saiga corpses and also with goats and cattle and try to protect native people. Somebody should start looking for radioactivity as soon as possible to discard or confirm this hypothese. I think is the most logical solution to this mystery.

https://www.youtube.com/watch?v=9a96nEk-f6Y

Looking at the radiation patterns from the Chernobyl accident itself:

http://users.owt.com/smsrpm/Chernobyl/glbrad.html

I doubt that radiation from a fire in the area around Chernobyl would be significant, especially in Kazakhstan.

The animals and people who died from the Chernobyl accident were exposed to thousands of times as much radiation as had landed anywhere outside of the Ukraine and Belarus.

The spread of radioactivity depends on wind and weather patterns, which aren't constant.

The article even mentions recent heavy rainfall in the steppe which could have washed radioactive particles out of the upper atmosphere.

It's not that hard to disprove this theory with a Geiger counter, so it seems worth checking.

Chernobyl melted down on April 26, 1986. So, most of the worst radioactive elements are long gone with large numbers of large mammals living in the area with minimal issue. That said, it may have indirectly contributed to a large die-off in combination with something else.

PS: A good example of a disease + enviermental issue is trench warfare. WWI trench warfare created a breeding ground for disease by both compromizing immune systems and packing large numbers of people together. The resulting pandemic is estimated to have caused significantly more death than the actual fighting.

>> So, most of the worst radioactive elements are long gone

You're wrong. Just facts:

Cesium-137 half-life 30 years

Strontium-90 half-life 28 years

1986 + 28 = 2014, 1986 + 30 = 2016

Less than half of strontium 90 is left, and vary close to half of Cesium-137 is gone, but together they make up a small fraction of overall radiation released.

Iodine 131 for example is one of the most dangrious isotopes after an event, but it's half life is 8 days.

Mmh... half of a bullet in the heart can kill you also...

But we need also to take in mind that when some of those compounds vanish in fact they aren't gone, they convert in other subproducts. Uranium creates Cesium (and Iodine I think, i'm not expert on this) when decays, so the real cesium should be now 50% plus X (where X is the cesium constantly created since the accident). And Thorium, Polonium, Radium...

What happens whith uranium in the subsoil when is burned in a fire?. Is its decay increased?

The half-life of uranium-238 is about 4.47 billion years and that of uranium-235 is 704 million years. So, they add meaningless amounts of Cesium.

Anyway, the dust is something like 95% less radioactive now than it was right after the event and you get far less dust from a contaminated forest fire than you would from the initial fire.

PS: Inside the reactor there is new stuff being generated from fission, but that's contained right now.

An article from the BBC [0] suggests that the animals' immune systems were compromised to the point that they were killed by two endemic bacteria. The suggestion is that they were in a weakened state due to this year's very cold winter and very wet spring. Also they observe that this species has frequent die-offs and repopulations. I suspect that would be more sustainable over the species' original range, which apparently stretched from Britain to China rather than just over one Kazakh national park.

[0] http://www.bbc.com/news/science-environment-32958032

Regardless of the actual cause of this mass-dying, what steps (if any) are being taken to secure the species? Are any saigas being kept in quarantine anywhere?

If one third of the total population can be wiped out within two weeks without prior notice, it would make sense to me to keep a small subpopulation in safety somewhere else.

Saiga is a little like the tasman tiger in that almost all zoos had some in the last 60 years but lost its animals gradually. Is a gregarious animal that needs a lot of space to be itself and is very fragile also, living short lives in zoos (less than 5 years). In the reproductive season males seem prone to forget all except sex, stop to eat and die easily (bassically sacrifice itselves for giving a better survival probability to pregnant females). Females have only one or very few babies in its entire live when in zoos.

ISIS (the International Species Information System) is a software/database used to trace all rare animals captive in zoos all around the world.

http://www2.isis.org/

After ISIS this species could be very rare in zoos currently with an entire world zoo population of maybe 2-4 specimens only: A couple of females in Moscow at least. Dallas, Cologne, Seoul, New Jersey, Beijing, Berlin and San Diego had saigas in the past but it seems that no one survived until today.

The species does much better in semi-captive environments. At least a place in Ukraine (and maybe other in Roskow and Palmyra) have small herds of 50-250 animals running free in big enclosures. The problem is that we know that those herds can be entirely wipped in the blink of an eye.

Illegal poachers also killed in 2014 the equivalent to many times the entire captive world population.

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