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Pioneering study finds more than 200,000 rats in Barcelona’s sewers

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Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#31

Post by lostlogin »

joecool1029 wrote: post #30
crispyambulance wrote: post #28

Earlier quoted context omitted.

> can we release a rat specific poison or is that impossible without harming the entire ecosystem? Many cities, like Baltimore, have an entire department devoted to "rat eradication" ( https://publicworks.baltimorecity.gov/Rat-Eradication ). Some have a "rat czar" "Eradication" is a bit of a misnomer because it is not possible to actually eliminate rats from a city. The goal is to keep them from getting out of contro…

>"Eradication" is a bit of a misnomer because it is not possible to actually eliminate rats from a city. It’s been done before: https://www.thecanadianencyclopedia.ca/en/article/rat-contro...

And it’s not a long way off being tried in New Zealand, which has (distant) goals of being predator free. Presumably this excludes humans.

Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#32

Post by lostlogin »

pc86 wrote: post #23
onetimemanytime wrote: post #2

I lost count after 200,003 rats :) Do rats serve a useful (for us) purpose there? If not, can we release a rat specific poison or is that impossible without harming the entire ecosystem?

Why do we need to remove them if they're not useful to humans? Ecologically I think it's hard to estimate the impact of removing an entire species from a given area.

Yes. When they are not native they can be very harmful - for example they badly damage bird life in New Zealand.

Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#33

Post by lostlogin »

adrianN wrote: post #13
zimablue wrote: post #5

Earlier quoted context omitted.

https://www.theverge.com/2015/5/13/8592817/rat-patrol-new-yo... The guys who do this professionally/successfully in a sparsely populated place with everyone helping and the advantage that rats can't survive outdoors don't think it's possible in cities. Big problems with poison: Rats are harder than you think to poison, they're both sceptical of new food and adapted to survive lots of poisons Evolution will work again…

AI gun turrets in the sewers.

Not quite there, but this thing is successful. It’s a self resetting trap, with its kill attracting more target species. Refilling if after ~25 kills is more expensive that resetting a manual trap, but the labour cost is ~25x cheaper. https://goodnature.co.nz

Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#34

Post by tetrep »

interfixus wrote: post #22
majos wrote: post #19

Earlier quoted context omitted.

> I have been lied to by a rat ...elaborate?

Rat teaches me to feed her when she tattles her tray. But I won't do it until everything's been eaten, also the boring bits. Then suddenly for weeks no trouble whatsoever - when she rattles her tray, it's empty, everything gone. Until one night, hidden behind a doorpost, I watch her methodically clean out the boring bits and bury them under floor pellets. As soon as the tray is empty - rattle rattle rattle. This was…

How do you know it's deceit? It seems like you could get similar behavior if you filled two trays, one with food and the other with trash, and never provided food unless the trash tray was empty. You're training the rat to empty the tray.

Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#35

Post by RobertoG »

nandshab wrote: post #14
charlysl wrote: post #8

Earlier quoted context omitted.

Do they wear yellow ribbons?

Yes. They also run away and escape the place like rats when the law rightly comes after them.

I think that, as you are so fond of the letter of the law, in the future you should try to make an effort and remember this:

From: https://news.ycombinator.com/newsguidelines.html

-"Be civil. Don't say things you wouldn't say face-to-face. Don't be snarky. Comments should get more civil and substantive, not less, as a topic gets more divisive. "

-"Eschew flamebait. Don't introduce flamewar topics unless you have something genuinely new to say. Avoid unrelated controversies and generic tangents."

-"Please don't use Hacker News primarily for political or ideological battle. This destroys intellectual curiosity, so we ban accounts that do it."

Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#36

Post by qubax »

Tharkun wrote: post #21

200k doesn't seem like that much. Rats aren't very big, and Barcelona is a pretty large city, with a population of about 1.5M humans. I would have expected more, having grown up in a rural area where there's a lot more mice, rats and other critters than one per 7 humans.

Yeah, that number seemed low to me as well. I always assumed there would be more rodents in a city than humans. Odd to see that there are a million more humans than rodents in barcelona.

Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#37

Post by ByThyGrace »

interfixus wrote: post #22
majos wrote: post #19

Earlier quoted context omitted.

> I have been lied to by a rat ...elaborate?

Rat teaches me to feed her when she tattles her tray. But I won't do it until everything's been eaten, also the boring bits. Then suddenly for weeks no trouble whatsoever - when she rattles her tray, it's empty, everything gone. Until one night, hidden behind a doorpost, I watch her methodically clean out the boring bits and bury them under floor pellets. As soon as the tray is empty - rattle rattle rattle. This was…

> Others picked up on that habit, and yes, it spanned generations.

It's memes (in the evolutionary sense) all the way down.

Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#39

Post by toast0 »

onetimemanytime wrote: post #2

I lost count after 200,003 rats :) Do rats serve a useful (for us) purpose there? If not, can we release a rat specific poison or is that impossible without harming the entire ecosystem?

Barcelona has very old sewers, which means there are many places for rats to gain entrance to the sewers, as well as places to live and hide. It's not a battle that's easily won.

Modern sewer systems separate storm runoff from sanitary sewers, and try to keep the sanitary sewers sealed off from animals. It's hard to change the infrastructure under a bustling city though, so most major cities tend to have the sewers they were built with, or whatever was retrofitted when it became apparent that sewage in the streets was worse than the expense of building a sewer system. However, rats are clever and do occasionally find their way in and around modern sewers as well.

Re: Pioneering study finds more than 200,000 rats in Barcelona’s sewers

#40

Post by Idontagree »

adrianN wrote: post #13
zimablue wrote: post #5

Earlier quoted context omitted.

https://www.theverge.com/2015/5/13/8592817/rat-patrol-new-yo... The guys who do this professionally/successfully in a sparsely populated place with everyone helping and the advantage that rats can't survive outdoors don't think it's possible in cities. Big problems with poison: Rats are harder than you think to poison, they're both sceptical of new food and adapted to survive lots of poisons Evolution will work again…

AI gun turrets in the sewers.

Off topic, but you really think there arnt automatic turrets, seems very feasible today, especially in a situation like a sewer where you really dont have to worry about shooting the wrong (moving) thing.
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