Magpies and crows are using “anti-bird spikes” to make nests (2023)
78 comments
·March 10, 2025baerrie
mmooss
In the OP:
But for the magpies, there was an additional layer of intrigue; not only were the birds using the spikes to build nests, but it’s possible they were also employing the devices for their intended purpose—to ward off other birds. “It’s a very natural behavior,” Hiemstra says. “We think these spikes are for nest defense."
TheSpiceIsLife
That’s exactly what they are, it says as much on the box.
lupusreal
Crows going for a Mad Max aesthetic for defense and deterrence seems both incredible and simultaneously unsurprisingly.
CTDOCodebases
“The impediment to action advances action. What stands in the way becomes the way.” ― Marcus Aurelius
BSOhealth
Researchers are doing all kinds of cognitive studies on how birds (and other animals) use tools. Has anyone looked into the potential impacts (good and bad) for wide scale introduction of proven tools for use by other animals?
Off the top of my head, if a tool is made of plastic for example, we’d be littering our environments with questionable trash.
But conceptually, what’s the downside to leave a huge pile of defensive materials like bird spikes in the forest to help promote nest health?
Stopping short of given them weapons of course. (Shout out to the other comment about training animals to dismantle barbed wire.)
mmooss
> Has anyone looked into the potential impacts (good and bad) for wide scale introduction of proven tools for use by other animals?
That is interesting. What if we designed tools for use by corvids?
> conceptually, what’s the downside to leave a huge pile of defensive materials like bird spikes in the forest to help promote nest health?
We'd be supporting one species, the prey, over the other, the predator. Why? Do we mean to apply vegan principles to animals? What happens to the predators? How do animal rights apply? Conceptually, it's really a difficult question.
gtirloni
Unless there's an imbalance caused by human activity, I'd say we are better off leaving the birds and their ecosystems alone.
aradox66
The "leaving ecosystems alone" ship sailed almost everywhere on Earth tens of thousands of years ago. Humans have always been a part of, and had impacts upon, the ecosystems we've lived in. Certainly moreso in recent centuries.
Not to say that further interventions will be helpful in "reestablishing balance".
Even the concept of "balance" or homeostasis has long been recognized to not really exist in any ecosystem.
__MatrixMan__
I agree, but I would be curious about cases where nature could reclaim habitat faster if we give it some tools for the job. I can't really think of what those tools might be off hand though--apart from some kind of weapon/disease that better keeps humans away at marginal detriment to the user/host.
Suppafly
>I agree, but I would be curious about cases where nature could reclaim habitat faster if we give it some tools for the job. I can't really think of what those tools might be off hand though--apart from some kind of weapon/disease that better keeps humans away at marginal detriment to the user/host.
That's an interesting line of thought. The only thing that comes to mind is something like giving them fancy hats or paintjobs to encourage more reproductive success in declining species.
mulmen
Don’t we already do this with artificial reefs?
crooked-v
For a lot of animals like crows, their ecosystems are "human activity" now.
fullstop
Last summer I made an attempt at befriending a crow. It actually went pretty well, but the treasures that he brought me blew my mind:
* French fries
* Cooked pasta, maybe baked ziti?
* BBQ ribs, but just the bone with some sauce on it
* Chicken nuggets
* One dead bird, conveniently opened for me
* Several whole dead baby chicks
* One baby chick's head
I would shake my car keys when I put the food out, and it would show up a few minutes later, but I never figured out if it just saw me or heard the keys.
Here's some video clips of my buddy:
https://i.imgur.com/4ZQb7L3.mp4 https://i.imgur.com/B4DBLxg.mp4
edit: make the links clickable
al_borland
They could become dependent on those tools and then if humans stop, the animals will die the tool supply drops.
FredPret
I'm impressed by this crow's beak-work: all the spikes are oriented inward and covered in leaves, making that nest very strong and not spiky at all.
pelagic_sky
Cockatoos just rip them out for fun. https://www.reddit.com/r/australia/comments/rga3pf/cockatoo_...
porphyra
Interesting but I have a hard time imagining how a nest made of anti-bird spikes could be comfortable. Do they actually find it to be nice? I guess corvids are super smart and wouldn't accidentally get tricked into making an uncomfortable nest due to man made materials...
throwanem
I saw an osprey pull a three-foot fragment of steel wire out of a wire rope on a tramp steamer one time. Damndest thing you ever saw, he kept circling and grabbing at this cable with his talons and I thought he was attacking or something, but I got my camera up in time to see him fly off with this twist of wire as long as his wingspan, pulled up under him like a fish. They love human detritus as structural material in their nests, which can be six feet across and four deep.
pixelbath
TFA addresses this directly:
> For the crows, the spikes seem purely structural, a material used to fashion a solid foundation. In both crow nests, the wires were incorporated into the base–interwoven with the points facing inward, below where a softer nest cup would sit. But for the magpies, there was an additional layer of intrigue; not only were the birds using the spikes to build nests, but it’s possible they were also employing the devices for their intended purpose—to ward off other birds.
nicoty
The article says the birds make different nest configurations, with one incorporating a softer cup layer on top of the spiky layer made with the spikes and another configuration using the spikes as part of a dome on top of the nest.
pbalau
Spikes are only uncomfortable if you sit on the spiky end.
mechanicum
Relative to their traditional construction material, twigs, it’s probably no worse.
NobleLie
My take is its less so about being physically comfortable, but there is a different type of comfort by the protection of the nest from predators. It's like being uncomfortable to have peace of bird mind, in other words.
xattt
It would be interesting to determine whether the serum cortisol differs between those living in spoke nests versus those without.
My assumption is that it is indeed elevated, as the “residents” are constantly mindful of their movements (and therefore more stressed) to avoid being poked.
SunkBellySamuel
It's more about sending a message than the comfort. Up the tweet!
fullstop
And then there are the doves, birds notorious for making the most lackluster of nests. They will lay eggs right on top of the spikes.
When you see the nests, it is amazing that doves / pigeons exist at all. They must survive out of spite and numbers.
Check out /r/stupiddovenests on reddit for some good examples.
maeln
It is because most pigeons we see in cities are rock pigeon and were usually making their nest in cliff, crevases and rock formation[1]. Not in tree. Therefore, they never needed to make such artfully crafted nest since the rock was already providing enough shelter. This is also why they are very adapted to live in cities, because our concrete jungles are actually closer (in their verticality, materials, and relative lack of trees) to mountainous terrain than to a jungle.
[1] https://en.wikipedia.org/wiki/Rock_dove#Distribution_and_hab...
alnwlsn
I've heard it said that the terrible nests are more to stop the eggs from rolling away. Apparently it was easier to evolve the ability to go get a stick than make square eggs.
fullstop
Wombats were so close
fullstop
Ah, interesting, that makes sense. I will still laugh at their "nests", though. :-)
harimau777
However, some pigeons are a little extra:
https://www.boredpanda.com/pigeon-poppies-nest-remembrance-d...
zdragnar
We don't have too many rock pigeons out in the country where I live, but we do have plenty of robins (American Robin / Turdus migratorius, to be precise), and those have to be in contention for world's dumbest nest builders.
Suppafly
>When you see the nests, it is amazing that doves / pigeons exist at all. They must survive out of spite and numbers.
They've basically evolved past the point of needing nests but still have some basic instinct to create them.
bell-cot
Could birds be trained to tear down military barbed wire & razor wire defenses?
(Or are the birds here AWOL from their training camp?)
lexicality
While corvids can use tools, I think they'd probably struggle with a pair of wire cutters
lores
To the laboratory!
sambull
obviously lasers, corvidae with lasers
marcosdumay
And that was how everybody on the North hemisphere went blind...
pelagic_sky
Cockies would gladly do the job for free. https://www.reddit.com/r/australia/comments/rga3pf/cockatoo_...
nonrandomstring
Well we've used pigeons fr missile guidance before [0], and for messaging [1], so birds have a firm place in the military including having their own special units [2]
More generally, the history of warfare is all about taking the enemy's resources and using them as weapons against the foe. This will be a defining feature of future cyberwar and AI - everything we build to "protect ourselves" will at some point be repurposed to advantage an enemy.
[0] https://en.wikipedia.org/wiki/Project_Pigeon
[1] https://en.wikipedia.org/wiki/War_pigeon
[2] https://warfarehistorynetwork.com/article/warfares-unsung-pi...
mr_toad
Geese have also been employed for security including by military forces.
codedokode
Sadly Wikipedia doesn't describe a specific mechanism that helps pigeons to navigate. I wonder do pigeons simply fly high enough that they can see hundred miles around?
nonrandomstring
They use magnetism AFAIK
webdoodle
Dolphin's were trained to bypass enemy underwater defenses to plant explosives on enemy ships while they were in there home port. They were also used to find mines and other underwater devices to be disarmed.
Most birds just aren't big enough to do real damage to barbed wire or razor wire defenses. Now if you could somehow train the birds to harass a herd of cattle into running down the fence, that might work. Sort of like the Hitchcock movie The Birds.
internet_points
reminds me of the BE UNGOVERNABLE dog https://www.reddit.com/r/blursedimages/comments/u8o03f/blurs...
Are there other good examples of animals subverting restrictions?
harimau777
Checkout the image at the top of this page! (I don't know if the blog itself is any good. I'm just posting it for the image!)
Suppafly
That's such a great pic. I wonder what the sign is supposed to be for, it's not like birds respect signs. What is it telling humans to do?
marcosdumay
Oh, if the sign is real, it's certainly a joke.
People do create those a lot more than one would expect.
fragmede
It's so the police arrest and cite the bird for breaking the law.
internet_points
haha great :-D
_kst_
Reminds me of the rats we used to have in our garage, that had built nests from our dryer lint.
Our dryer lint was largely cat hair.
vittore
I find it unfair that there is no Audubon location in Audubon, NJ :p
Saved the link for more bird news.
btown
Both were independently named for https://en.wikipedia.org/wiki/John_James_Audubon !
Tesas
They work like springs in the mattress and they add the fluff to the top. Additional benefits are that the spikes don't get chewed by rodents and remain there for the following year
It seems likely to me that the birds have suffered by these spikes and repurpose them as much for the message they send to avian predators as their structural merits. It is like humans wearing the head of a wolf or other things to communicate they are a threat to would be interlopers.