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How to tell a raven from a crow (2012)

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Re: How to tell a raven from a crow (2012)

#72
post #65

Wish I'd known this when I was randomly attacked by raven or crow in BC, then I'd only dislike one of them.

Just because you don't understand its reasons doesn't make it a random occurance. I'm guessing you were near a nest or a fledgling, but that's just my non-educated guess.

Another possibility is that you looked like a former 'enemy' of crows. Crows can remember people who mess with them for up to two years and seem to be able to communicate that information among their peers. There is an excellent documentary about that behavior and it may have even been about scientists in the BC area.

They wore masks to test whether the information could be passed down from generation to generation. They found one crow offspring that still recognized the mask its parents had been trained on.

I believe it was called "The Intelligent World of Crows". It was excellent.

Re: How to tell a raven from a crow (2012)

#73
post #54

In Northern Europe, the subspecies Corvus cornix, hooded crow, is easy to tell apart from the raven due to its grey body parts. For this reason there is never any doubt what you see, but this also has imprinted the other body differences in my mind. I don't think it is hard to tell the black Corvus corone from raven due to this.

They are beautiful and it almost looks like silver. I loved seeing them when I was in Finland.

Re: How to tell a raven from a crow (2012)

#74

A bigger challenge is to differentiate a Northwestern Crow from an American Crow. > It is smaller than the American Crow and has a more nasal call, but it is so similar that the two may in fact be the same species. https://www.allaboutbirds.org/guide/Northwestern_Crow/overvi... I didn't even realize that my area had an apparently different crow than everywhere until I bought a birding book.

Actually, recent research indicates that these two species began differentiating themselves a long time ago, but their lineages have since converged: they now interbreed freely and there's no reliable way to tell the two species apart: https://twitter.com/dlslager/status/1072353359041085440

It's been really interesting to talk to birders I trust about this. The rough consensus is, most people think they're the same species and will get merged back together soon, but some are very attached to the distinction between the two, haha.

Birds are so cool! I think it's fascinating that we're still learning new things about this stuff all the time.

Re: How to tell a raven from a crow (2012)

#75
post #43

Here's a very cool Google Creative Labs experiment that used tSNE to organize thousands of bird chirps/songs/calls. The result is an interactive map that groups similar bird sounds (click/tap to play any of the sounds): https://experiments.withgoogle.com/ai/bird-sounds/view/ source code: https://github.com/googlecreativelab/aiexperiments-bird-soun...

I feel like these kind of cool tech demos paired with a highly motivated and technically savvy phd student would lead to some interesting models in research papers with accompanying demos.

On a related note, there's an app that will identify bird species based on photos that you upload (http://merlin.allaboutbirds.org/photo-id/), and it's powered by "Visipedia", a collaboration between a Caltech and Cornell research group (https://vision.cornell.edu/se3/projects/visipedia/?__hstc=75...).

I remember how nascent the tech was when they first started releasing it in 2011ish and it's incredible how good it is now. Really awesome stuff.

Re: How to tell a raven from a crow (2012)

#76

Earlier quoted context omitted.

For me, it was watching them play for hours outside the office. Sometimes a pair would fly together for awhile, then one would dive at the other, who would flip over at the last instant. There was no reason for them to do this; they just had enough free time to screw around.

That's a sure sign you are watching ravens, not crows. Ravens can play together in the air in ways crows never do.

Ravens are apparently one of the smartest animals.[1]

[1] https://news.nationalgeographic.com/2017/07/ravens-problem-s...

Re: How to tell a raven from a crow (2012)

#77
post #59

Crazy to see this posted today. Last night my wife and I were on a reservation in Arizona and watching the birds. She googled this very topic. Then when I looked at HN today, here it is! I showed it to her and the first thing out of her mouth was, “Is Facebook listening to me?” Then I had to explain that HN is human-powered and the chances of Big G and Facebook and HN sharing data is pretty close to zero.

Similar spooky things happen to me with online adverts. I happened to mention to a friend that I want to adopt a dog. Lo and behold, for the next 5 days, all I see is dog adoption/dog food adverts. It's happened twice to me, and both times, the ads have been so out of the ordinary from my usual ads, that I actually took time to notice them! I'm fairly certain Google is listening in to conversations for ad targeting.…

So you adopted a dog. How did you go about buying all the things you need when you suddenly have a dog? Stores? Online? Amazon? Did you use a credit card? Did you research dog food? Post on Facebook or Twitter about how you were getting a dog?

Re: How to tell a raven from a crow (2012)

#78
post #59

Earlier quoted context omitted.

Similar spooky things happen to me with online adverts. I happened to mention to a friend that I want to adopt a dog. Lo and behold, for the next 5 days, all I see is dog adoption/dog food adverts. It's happened twice to me, and both times, the ads have been so out of the ordinary from my usual ads, that I actually took time to notice them! I'm fairly certain Google is listening in to conversations for ad targeting.…

So you adopted a dog. How did you go about buying all the things you need when you suddenly have a dog? Stores? Online? Amazon? Did you use a credit card? Did you research dog food? Post on Facebook or Twitter about how you were getting a dog?

I didn't actually adopt a dog. I merely spoke about the idea of doing so to a friend.

Re: How to tell a raven from a crow (2012)

#79

Earlier quoted context omitted.

For me, it was watching them play for hours outside the office. Sometimes a pair would fly together for awhile, then one would dive at the other, who would flip over at the last instant. There was no reason for them to do this; they just had enough free time to screw around.

This video of a crow repeatedly "skiing" down a roof changed my view of how animals play - I thought it was all "practice-fighting" but this crow seems to be playing "just for the fun of it". https://www.youtube.com/watch?v=1WupH8oyrAo

This is a hooded crow hammering / trying to kill what probably thinks is a prey. Seems more frustrated than happy. The easiest crow to identify in Europe, being gray and black.
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