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Comment by lloeki | Hacker News Reader

> Cooper’s hawk is on a rather short list of bird of prey species that have successfully adapted to life in cities. A city is a difficult and very dangerous habitat for any bird, but particularly for a large raptor specializing in live prey: you have to avoid windows, cars, utility wires, and countless other dangers while catching something to eat every day.

Peregrine falcons adapted quite well, and they're much more sizeable. That said, their size make them very apt to hunt pigeons, so this could be a less risky niche to hunt for; I mean, pigeons usually fly higher up than sparrows.

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The Black Redstart evolved to live in holes in cliffs and the like, and never used to be widespread in the UK. After the second world war, cities all over the south were bombed out, and they moved into the deserted, derelict bombed areas in great numbers. As the bomb sites were cleared and the cities redeveloped, their habitat was eroded. But at the same time, Britain was de-industrialising, and they moved into the abandoned factories in the North. As those now get redeveloped, they are losing their habitat again.

There's a couple of peregrine falcons with a live streaming webcam on top of Cathédrale Sainte-Cécile in Albi, south of France

https://albi.fr/environnement/les-faucons-pelerins

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

The City Hall of San Jose, CA, currently has a couple peregrine falcon young in a nest on its roof i believe. It’s relatively high up for the area.

You have the story of Flacco the owl who lasted 1 year in Manhattan after having spent his entire life in captivity.

https://en.m.wikipedia.org/wiki/Flaco_(owl)

Even his death (due to a collision with a building) was likely less because of his ability to survive, since he managed to learn all the skills necessary, and more due to the fact that his primary food source, rats in and around the city, were laden with rat poison.

We have consistently and regularly underestimated non human animals cognitive abilities which is frankly strange if you understand evolution since it would be strange for only humans to have a certain evolutionary feature such as intelligence and every other species to not have it at all.

> underestimated non human animals cognitive abilities

I think humans have done precisely what humans do: misunderstand. Unlike other animals, humans don't have the ability to understand creatures they have not studied for long periods of time.

We know animals are intelligent. But we don't know what intelligence means. Is it something we can use? no? then it is something we ignore. And it is most likely something we disrespect.

Live stream of Peregrine Falcon nest at the top of Sagrada Familia in Barcelona:

https://www.youtube.com/watch?app=desktop&v=TMRRsBh5GDI

I spend too much time on this...

In big Swiss cities, I believe its a red kite thats a common sight. I mean really common, always some of them up in skies in central Zurich, Lausanne or Geneva.

It feels surreal in best way possible, I come from eastern Europe and cities back home are always a mix of crows, pigeons and little birds, mostly sprigs and sparrows. Birds of prey - thats stuff for wilderness only.

One more thing to adapt to, not complaining at all though. To be clear - these are not megacities, but still sizeable enough to expect wilderness was driven away to mountains which are never too far here, especially for birds.

There are Peregrine falcons in my city. I remember walking downtown one time and seeing one on the sidewalk with a pigeon in its talons. All the commuters and I just walked around it. Really weird somehow.

Interesting, around here raptors hunt high, and if prey falls to the ground they abandon it; too dangerous to go down in the streets.

I almost ran one over turning in a car park in Edmonton. Backed up and it was still standing on the pigeon glaring at me. I drove around.

That's a hawk vs falcon hunting difference, not a city vs countryside one.

Quail won't take off if a falcon's shadow passes over them; they'll burst if a hawk's does.

London apparently has a high density of them (but high density still only means something like 40 breeding pairs), and some people are all excited about the prospect that they can do something about the rapidly rising wild parakeet population...

I'm having a hard time squaring away the image of grey gloomy London also being overrun with colourful tropical looking birds, I had to google it and see.

They’re surprisingly well adapted to a large range of temperatures because of the species found in temperate rainforests at higher altitudes. They frequently enough escape from pet stores and zoos that there are many sizable populations spread out around the world. The one nearest me is the infamous Pasadena parrots [1] which is made up of thousands of birds likely built up over decades of escapes. There are populations in Chicago, New York, Rome, Tokyo, and plenty of other cities in the world.

[1] https://www.lafieldguide.com/p/the-pasadena-parrots

Here are some pictures taken out of my home office window too:

https://m.galaxybound.com/@vidar/114256153547342202

And a short walk from mine:

https://m.galaxybound.com/@vidar/114582595390607406

They're everywhere at this point.

Those are fantastic photos!

Melbourne, Australia has a family of falcons living on the roof of 367 Collins St in the CBD. You can find some of the falcon cam footage on YouTube.

The other day when visited local city park (in South London) I spotted a Buzzard just chilling on the tree among pigeons.

Small, but majestic nonetheless.

Obligatory note that if you're from the US you are probably picturing a different bird than parent saw.

would you care to expound on that?

In the US, buzzard is pretty much always slang for a turkey vulture. The common buzzard in Europe/Asia is a different bird entirely.

> The common buzzard in Europe/Asia is a different bird entirely

Funnily enough in France:

- buzzard is "buse" (mostly - although not limited to - Buteo[1])

- there's an unrelated yet identically pronounced "busard" (Circus[2]).

- EDIT: oh, and "balbuzard" (Pandion[3] a.k.a ospreys)

[1] https://en.wikipedia.org/wiki/Buteo

[2] https://en.wikipedia.org/wiki/Circus_(bird)

[3] https://en.wikipedia.org/wiki/Pandion_(bird)

> Peregrine falcons adapted quite well, and they're much more sizeable.

I'm not sure what you mean. As far as I am aware -- and according to every source I've looked at in the last few minutes -- Peregrine falcons and Cooper's hawks are about the same size (length and wingspan are within 1-2 inches).

Peregrines are somewhat smaller and much more lightly built. I live in a nesting pair's territory which often sees transitory Cooper's; they're easy to distinguish both in flight and at rest. Male Cooper's are more peregrine-sized and hard to tell from sharp-shinned hawks sometimes, but that is an ordinary enough sexual dimorphism in birds.

Interestingly, while peregrines and accipiters like Cooper's share a habit of taking passerines in flight, the response of potential prey seems to differ. I frequently see songbirds mob a Cooper's; I can't think offhand of a time I've seen them respond to a peregrine other than by crypsis.

Sadly we don't have Cooper's around here so I have no experience with them, hence why I looked them up (see nearby comment) and according to that source found out they were on the smaller size and much smaller weight.

Around here the only ones who would dare mob a peregrine would be crows.

Sure. I'm just talking about the impression they give in life. But I suppose in that sense the other birds must find a peregrine much more striking, and it very belatedly occurs to me that peregrines no doubt look smaller and more gracile to me for the higher altitudes their stooping hunting habit would require. When I do occasionally see them on approach to their nearby nest, I'm struck by their relative size. So yeah, between that and reviewing my Sibley's the error here is mine, though - for that matter, likely also because - I do find all falcons rather streamlined and compact in impression compared with accipiters or buteos.

> according to every source I've looked at in the last few minutes

I may be mistaken but that's what I found:

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

> The peregrine falcon has a body length of 34 to 58 cm (13–23 in) and a wingspan from 74 to 120 cm (29–47 in)

> Males weigh 330 to 1,000 g (12–35 oz) and the noticeably larger females weigh 700 to 1,500 g (25–53 oz)

https://en.wikipedia.org/wiki/Cooper%27s_hawk

> Total length of full-grown birds can vary from 35 to 46 cm (14 to 18 in) in males and 42 to 50 cm (17 to 20 in) in females. Wingspan may range from 62 to 99 cm (24 to 39 in), with an average of around 84 cm (33 in)

> In northern Florida, males averaged 288 g (10.2 oz) and females averaged 523 g (1.153 lb). In general, males may weigh anywhere from 215 to 390 g (7.6 to 13.8 oz) and females anywhere from 305.8 to 701 g (0.674 to 1.545 lb), the lightest hawks generally being juveniles recorded from the Goshutes of Nevada, the heaviest known being adults from Wisconsin

(not putting the full regional rundown, just the biggest entry)

In my neighborhood in the East Valley in Phoenix, I’ve seen Cooper’s hawks, kestrels, peregrine falcons, zone tailed hawks, merlins, and one immature bald eagle. Along with the numerous turkey vultures and the occasional black vulture.

Plus pigeons are not exactly known for being incredibly smart or agile, so if you're big enough to take one down, you probably won't struggle too much for food.

Pigeons are actually known for being very agile, and are able to do vertical takeoffs and evasive maneuvers like a backflip loop immediately after takeoff, which is precisely to evade predators like falcons.

City pigeons just tend to become fat, lazy and used to suppressing their flee response around traffic and people.

Pigeons fly surprisingly fast and can outfly smaller raptors in a straight line. A stooping (diving) Peregrine will usually win. Its strike may decapitate the pigeon which tends to minimise the struggling

Except for the part where pigeon racing is an entire sport that relies on both their speed and intelligence

Except that it's not clear whether the intelligence† that underlies their homing ability is equally effective in helping them evade predators.

†Is "intelligence" even the right word here? I don't know. Much depends on how you define it, I guess, combined with the unknowability of the pigeon's own mental processes.

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