Japan Fights Crowds of Crows (2008) | Hacker News Reader

Japan Fights Crowds of Crows (2008)

nytimes.com

I live in Tokyo, and and if I become a billionaire, the second thing I will do (after starting a thrash metal guitar university for girls) will be to commission a Planet Earth II level documentary about the crows here.

They are fucking HUGE, they own the city (especially on trash-collection days), and they can go really high. When I moved back here I stayed a few weeks in a hotel on the 53rd floor. There were no pigeons, or any other birds I could discern, other than the fucking murder of crows who owned the place.

I now live on the top floor of a 9-story apartment building, and I am trying very hard to make friends with the two crows who have apparently successfully acquired the crow territorial rights to it, and live on the roof above me.

Anecdotal evidence suggests they won't shit on your balcony, or try to peck the back of your head, if you do so.

Also, as a child I lived in Bodega, California, and my house was featured in Hitchcock's The Birds. So I might be like, overcompensating a little...

When a coworker and I were in Ginza we spent an hour or so wandering around Hamarikyu Gardens there. That was the first time I saw one of the Japanese crows. At first, I thought it was a raven, but it was brazen enough to land less than 6 feet away from me, and I got to see how big it actually was.

It was taller than my knees.

Crows in the Pacific Northwest have this delicate little "caw caw" that they make. It's sort of endearing to me because of the association with home. When this thing opened its beak it was no little bit unnerving to me. No small "caw" passed from its beak, but rather a sound proportional to the size of the thing.

We backed away slowly.

>It was taller than my knees.

How tall in inches or centimeters?

Probably 28 inches or so.

That seems very large. I went looking for photos of crows in Tokyo, this NPR article[1] has several. They do seem to have more impressive beaks than N. American crows...

1: https://www.npr.org/templates/story/story.php?storyId=122291...

I could be overestimating. Regardless, it's an intimidating bird.

Wow, that's big - 2 and 1/3rd feet. The crows I see in cities in India seem to be not more than a foot or so in body length, and I've seen some from a few few away. But they can be aggressive when in groups (as in the sense of cawing more and flying around the person), if someone seems to threaten them by throwing or waving something at them. Never actually heard of a case of them pecking someone, but it could have happened.

Just googled for such info and saw this:

https://www.quora.com/Can-crows-attack-people

Yeah here in Australia, the neighbourhood magpie is the meanest bird you'd ever seen. But we have been feeding it for years, and it hasn't bombed us in a long time... except sometimes it swoops over my shoulder hitting my head with its wing tip. I'm still on alert during bombing season.

Also it still bombs my mum, it hates Asians.

Not to mention the ibises (waste high scavengers with long curved black beaks and no fear of humans) or the giant bats that swoop by your head at night.

You might be interested in a film called “Tokyo Waka”. The filmmakers call it a visual poem but it’s essentially a glimpse of Tokyo through people’s experience with the crowd.

Oops, crowd -> crows. It's about the crows.

The University of Washington in conjunction with PBS did a documentary on the crows of Seattle. UW does quite a bit of research on the local (and quite abundant) subspecies of crow, so it's rather interesting.

http://www.pbs.org/wnet/nature/a-murder-of-crows-full-episod...

>> They are fucking HUGE

Then you wouldn't like the "crows" near my house:

http://3.bp.blogspot.com/-C8cVvmw3vGI/VYdRFu0_VSI/AAAAAAAADf...

> Anecdotal evidence suggests they won't shit on your balcony, or try to peck the back of your head, if you do so.

Haha, this sounds like quite the protection racket. "Sure would be a shame if... someone pooped on your balcony!"

I was able to train the wild city-crows to stand on a certain part of my fence to receive unsalted mixed nuts. Cashews are like crack to them.

When I was a kid I went on a vacation with my family to a cabin by a lake. A man living in nearby had a pet crow. The crow would get cosy around our dining table outside trying to grab some food, so my mother chased it away once. After that for the next 2 weeks we stayed there whenever my mother would hang laundry to dry outside the crow would fly over and take a shit on my mother's clothes. There were 5 people in the family, but the crow would somehow always pick my mother's clothes. It was fascinating for me, that the bird was as intelligent as it was vengeful. This is a true story.

Corvidae are smart, and seem to have good memory.

I've heard that a good way to keep them away is to kill one, and hang up the corpse on display. Others will stay away.

They are smart indeed. Apparently they can remember faces (https://www.nytimes.com/2008/08/26/science/26crow.html) and colors (https://phys.org/news/2011-12-crows-colours-year-japanese.ht...) which is how I'm guessing the crow I've encountered knew which clothes specifically to take a dump on. Really fascinating stuff.

A large murder of crows had become a problem near where I live. The group seemed to get larger by the year. They'd turn clusters of trees black, and were incredibly loud. During a certain time of year when they showed up, they'd terrorize areas with vast amounts of shit. The local government poisoned a bunch of them (took several years to get approval). The crows got the hint and never came back again.

I was in Hokkaido, for a while. They have huge crows (I believe significantly larger than the ones that are found in Honshu) who are very clever and can be quite aggressive. I remember experiencing them taking a snack I had not even opened out of a bicycle basket to open and eat it. Another time, I went with my wife (my girlfriend at the time) to the zoo and she bought a meat bun and walked outside. The employees began screaming at her to go inside right away and no sooner had they said it than crows descended on her like something out of a horror movie. At the entrance to the zoo I saw them pecking the head of a crying boy trying to eat something. They get more aggressive around the zoo for whatever reason.

Anyway it's really something else.

In New Zealand I used to get attacked regularly by magpies, a large and aggressive crow-like bird, while riding my bike near trees where they were presumably nesting. They'd come at you from behind and swoop at your head, either passing very close to scare you, or even clawing at my helmet as they passed. Very frightening if you're not expecting it!

Apparently on some occasions people would get attacked seriously enough to draw blood. The weird thing is that as soon as you got off your bike and pushed it, they'd be scared off and wouldn't come near you. But something about bike riding seemed to drive them insane...

Fascinating, the first time I heard about this phenomenon is when this amusing video [1] was doing the rounds. Apparently it's a seasonal issue largely linked to them being particularly aggressive in their defence of newly-hatched broods. What's weird though is that in certain magpie-swooping zones, the swooping is selective [2]. It seems quite accepted that corvids can recognise faces and otherwise identify individual humans, but what makes it single out people that haven't attacked it is a real mystery.

[1] https://www.youtube.com/watch?v=YGGTcYfrEZU [2] https://www.theguardian.com/environment/2017/jun/28/when-mag...

Crows in Japan are definitely quite intelligent. They'll use traffic to crack open nuts by dropping them in front of traffic lights. After a car runs over them, they'll wait for the red light and then retrieve the now cracked open nut[1].

[1] https://www.youtube.com/watch?v=BGPGknpq3e0

> Mr. Ishihara angrily ordered the city into action after a crow buzzed his head while he was playing golf, city officials said.

So the mayor only acted when he was personaly bothered by the issue, apparently.

Golf is a frustrating game. I can easily see ordering the murder of all birds in Tokyo if a Crow messed up my birdie.

I've never played golf, so I can't say. I was more commenting on an example of a politician acting only when he's experiencing the problem first-hand.

Hardly an uncommon phenomenon, I must say.

keep the puns on reddit

>>> The crow explosion has created a moral quandary for Japan, a nation that prides itself on nonviolence and harmony with nature, because culling programs are the only truly effective method of population control.

No. Culling something like city crows is insanely difficult without resorting to poisons, a very dangerous option in a city. Crows are a problem all over the planet. Get some hawks, or whatever species of raptor is native to japan. A few pairs of nesting peregrines will keep the population in check. More importantly, the presence of raptures in an area changes the behavior of prey species. The crows will be far less bold.

Except eagles. Eagles are wimps. I see them harassed and chassed away by crows almost daily.

I'm in San Diego and I regularly watch crows fight hawks in midair, which defiantly ignore them.

Hawks dive on prey from altitude, at speeds higher than anything can achieve in level flight. They dive with their wings partially retracted. It's hard to see. The attack is over in a second or two. So if you see crows fighting back then the hawk is moving slowly, probably working its way back to altitude and unable to respond.

The idea that the Japanese are uniquely in harmony with nature is questionable too, when you think about their love of covering every square inch of places in concrete and asphalt.

Nevermind their propensity for hunting all manner of life in the sea, especially whales, even after being told multiple times from multiple committees worldwide to not kill every last pregnant female.

I am not sure "killing every last pregnant female whale" is a fair characterization of Japanese whaling practices.

There actually are initiatives using hawks (鷹).

The city of Portland, OR hired falconers and their birds to keep the crows from hanging out on certain streets downtown:

https://www.instagram.com/p/BdDP_xwhg62/

http://www.oregonlive.com/portland/index.ssf/2018/02/latest_...

A good start would be to use trash cans. At night people put out bags of trash on the street to be picked up in the morning.

Newer buildings have a "trash room" of course, but mountains of garbage in the street in busier areas are still the norm in some places, on collection days.

I just came back from Japan, crows all over Tokyo, but they are pretty much disappear after 9 AM, if you're an early riser you will see them everywhere!

Interesting, I only saw a few over a period of a couple of weeks in Tokyo.

We have lots of crows here in Norway where I live but not the problem that Japan has. I suspect that part of the reason is that we do not leave rubbish in plastic bags on the street. Food waste goes into a solid plastic wheelie bin with a substantial lid.

> solid plastic wheelie

The local squirrels drill right through that "solid plastic" in moments to get at the goodies inside. I put my garbage in an old fashioned galvanized can, and transfer it to the company toter only on pickup day.

I love the bit about crows making decoy nests. :-)

Isn't it called a murder? A murder of crows.

I'm guessing the title would have sounded like the crows are being murdered:

> Japan Fights Murders of Crows

it is. English is really rich in this aspect. My favourites are: - A Conspiracy of Ravens - A Vortex of Vultures

It’s only murder if it’s unlawful. It’s a killing, a slaughter though.

Edit: never mind, you tought me a new definition.

So Japan has a high murder rate?

I was reading Kafka on the Shore and thinking that the frequent mention of crows must have some symbolic value. Then I visited Japan and I understood: Murakami was just being realistic. Crows are everywhere. It is quite ominous to walk through a quiet Japanese park (and I mean dead quiet) and suddenly see a huge flock of crows appear.

Is there a reason why this could this not be brought under control naturally by providing habitat for predator species, like hawks or eagles? Apparently Peregrine falcons have done quite well in urban environments [1]

[1] https://www.telegraph.co.uk/news/earth/earthnews/3324408/Per...

Crows are very underrated in terms of intelligence.

Well naturalists rate them very highly at least [0]. In my own experience as a driver crows are some of the few animals that understand cars. Horses, deer and dogs will happily run in front of an approaching car while crows on roadkill fly away as a car approaches and return as soon as it has passed.

[0] https://en.wikipedia.org/wiki/Corvidae

Not really. The Corvidae family of birds are widely known as some of the most intelligent animals.

> Tokyo says the number of crows it has counted in large parks rose to 36,400 in 2001 from 7,000 in the late 1980s, prompting a trapping plan that cut the numbers to 18,200 last year. However, ornithologists say that the actual number in Tokyo is closer to 150,000 birds, and that some crows may have moved to different areas to avoid the traps.

Dealing with these crows seems like it would be a good computer-vision/ML/AI/data/drone/"weapons" problem. Killing baby crows in the nest in Tokyo a la [1] would necessarily remain human work, but open-air operations could be done with drones.

Would there be a non-lethal approach to harassing crows that would drive them away? If a program chooses the lethal approach, what weapons and disposal methods? How much would a program cost, and would that cost be offset by savings on the extra garbage-collection efforts that crows cause in [1], and other factors? How would crows adapt their strategies? Could similar approaches be used for rats in NYC, for example? Would there be downsides to a NYC without rats, a Tokyo without crows?

How long till technology would make a program like that viable? If Google is working on automated drone human targeting, the crows-in-Tokyo seems like a much more constrained problem.

[1] https://www.youtube.com/watch?v=lWw_87A1t-o

EDIT: technological viability.

I'd suggest that non-lethal intimidation wouldn't necessarily work on crows. Crows routinely mob other threat birds (e.g. buzzards, in my experience) and even a single crow will chase a buzzard off.

Firing bullets or similar from a drone might not be a good idea in a crowded urban environment (damage to people and / or property).

Drones deploying nets to catch them (or at least make them fall out of the sky)? Perhaps, until the crows cotton on, to the extent of swarming the drones.

Self-detonating proximity drones? Have the same issues as firing bullets (falling debris) and not very economic.

Lasers. Might incapacitate, kill, or blind crows, would need to avoid collateral damage. Maybe with remote human intervention on the kill switch, one person per bank of 50 drones.

Nathan Myhrvold supposedly displayed a mosquito-killing laser photonic fence some years ago [1]. A laser to deal with crows would need to be much more powerful.

[1] https://www.fastcompany.com/3059127/what-happened-to-the-mos...

Firing drone-lasers powerful enough to burn or blind might not be a good idea, especially where beams could bounce off reflective surfaces.

A ground-based laser would pack a lot more power.

I know of some towns in upstate NY that employ "crow hazing" techniques to harass and eventually drive away large flocks. Typically these groups tend to use nonlethal (and as non physically damaging as possible) methods like air rifles and lasers, and sometimes just bright lights.

http://www.wwnytv.com/story/37317955/crow-hazing-in-watertow...

No, we're not going to go around maiming animals just to satisfy your thirst for drones and lasers.

Clean kill or nothing.

Could drones be used to fire nets at the birds? The birds could be encapsulated so they can't fly away and then either left to starve to death or be picked up for execution later.

Surely it can't be easy to design a reliable system for storing, firing and reloading the nets? How about designing an extra sticky type of silly string? It could be prayed on the crows until they are unable to fly. All in the form of an aerosol can.

Armed drones flying around killing crows using machine learning seems like an idea with a huge potential for unintended consequences.

Google may be interested in the problem.

Good idea. Though, I suspect the crows would beat the drones. I think it would be an arms-race of sorts. Crows constantly adapting to the drones changing tactics. I would love to see this play out.

Here in the States we have Coyotes. The governments of this country have tried in vain over a century to kill off the coyotes but their intelligence and other traits have kept their numbers growing.

They could subsidize the effort with a TV show(someone call amazon), I know I would definitely watch an arms race between drones and crows.

There are much easier and much more natural solutions. Chief among these is employing Falcons, which are like drones except they're alive, much faster than crows or drones, and incentivized (by food).

Sometimes you don't need a technological solution, sometimes what we already have is good enough and it doesn't get much better than simply using the existing circle of life.

I want to see 'Crow Patrol' the anime.

2008, still very interesting.

I always wonder why aren’t there “ten years gone” follow up articles. Like what has happened with crows in Japan since 2008? Media should do more of that as a matter of routine.

Sensationalism has thoroughly overwhelmed journalism.

Agreed so much. Can't even count the number of times I thought 'what would have happened to ... after all these years?'. From time to time I do see for example documentaries going back to places years after a disaster (Fukushima, BP Gulf, ...) but that's from actively looking for them. Hardly ever this pops up in the news. Well, it's maybe not literally 'news' but if I see the amount of rather trivial events which do make it to the news I really think some money in media/journalism could be better spent. They spend weeks and weeks of reporting the same thing again and again when some major event is fresh but then it all dies out.

The media seems to only rehash an event if it contains political talking points they can use. The only follow ups you'll find is in journals/Google scholar.

Wikipedia can sometimes be good for this. But I agree, if they report about something they should report on what happens later.

Totally agree with this idea of long-term follow-up articles, I wish there was more of that.

That's the main reason I went to the comments, to see if anyone here had an update.

murders, pl

Around here it's Pigeons, but they seem to occupy the same niche as these Crows. Part of the problem is that not only are they good scavengers, but some people actively feed them causing not only a huge mess (piles of rotting bread dumped on the pavements), but it encourages the birds to congregate and multiply.

Can't we just make pigeons and crows kill each other somehow?

Let them run for office?

Pigeons aren't even native to North America, but they're so well suited to urban environments it's doubtful they're going anywhere.

A week or two ago I guess it was mating season because I saw a bunch of them doing courtship dances.

North America once had a native pigeon, with an estimated population of 3-5 billion. They were driven to extinction due to hunting and habitat loss.

https://en.wikipedia.org/wiki/Passenger_pigeon

Right. But usually pigeon means rock dove.

Not sure why I was voted down here. Do we have some closet pigeon feeders on hacker news?

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