I learned from the book "How to Hide an Empire" that an initial motivation for US imperialism in the Caribbean was to harvest bird droppings for fertilizer, even to the point of conflicts with Britain and Venezuela: https://www.vox.com/2014/7/31/5951731/bird-shit-imperialism
This law is how the US originally got possession of Midway, which became very well-known during WWII (I always wondered how the US got it originally):
https://en.wikipedia.org/wiki/Midway_Atoll
You need only nitrogen for explosives, but nitrogen, phosphorus, and potassium for fertilizer. Therefore guano (which contains all three) is overkill for explosives but great as a fertilizer, while synthetic nitrogen compounds are insufficient as a "complete" fertilizer and have to be supplemented with the two other elements from other sources.
"As a manure, guano is a highly effective fertilizer . . . Guano was also, to a lesser extent, sought for the production of gunpowder and other explosive materials. The 19th-century guano trade played a pivotal role in the development of modern input-intensive farming."
Chicago should build new designs of these around Millennium Park, and maybe reduce their strife with what is both native wildlife and a productive resource. They really can't stand pigeons.
I doubt it. "guano" comes from an Andean language [0], while "iguana" comes from thousands of miles away, from the Caribbean [1]. Both are pre-Columbian words that entered English via Spanish.
(I'm not an expert; I just looked up the "etymology" links on Wiktionary).
I do not know. I never owned pigeons. But yeah: Eating them. Eating their eggs. Using them as mail pigeons. Selling them to BF Skinner... Or some other use I might have never heard of entirely. I mean, the idea the people kept pigeons for their droppings was completely new to me as well.
I remember seeing a modern experimental structure that invites pigeons to nest, but due to its design, the nests are not stable and the eggs fall down, thereby reducing the pigeon population. The structure itself was similar to these in size and shape, maybe inspired from these.
On our small farm, we use ducks for fertilizing our fruit trees. We put a temporary fence for them around a tree.The ducks are out during the day, at night inside the fence. After a week or so we move the fence to another tree.
Profits? The Green Revolution[1] is credited with widespread reduction of poverty and hunger. The Haber Process provided the fertilizer which was one of the keys to the revolution.
The green revolution is also responsible for turning farming in to an industrialized process that destroys soil and farmer well-being. Not everyone thinks it was a good thing for the world.
Actually, the government banned synthetic fertilizers with a view to improving the country's highly negative trade balance. It was an extreme measure improvised in a rush by a country on borrowed time. Sri Lanka isn't even being supplied in oil now, nothing to do with the ban.
I think they nest in pairs, so there would likely be plenty of room.
I understand that they are defensively territorial, and unpleasant when nesting near people.
"The young will double in size in a day and a half. Making them one of the fastest growing vertebrate in the world...
"In another study, Pigeons were able to recognize themselves in a mirror. This makes them one of six species and the only non-mammal to be able to do so...
I find this hard to believe. There has to be a lot more to attracting the pigeons?
Reminds me of a recent trend, at least in Sweden - Bee hotels. Small bird house like things that are said to attract bees. Everyone started selling them for a while. I bought a few of them to friends. But I don't think they got used.
Putting up a structure and expecting it to just work seems a bit optimistic. Is there more to the secret sauce?
Considering that keeping pigeons from nesting in buildings and structures is an industry in itself in many cities, I find it very easy to believe a tower made for the purpose will attract then!
If they're the ones I'm thinking about, with the pieces of bamboo, holes drilled in wooden blocks, etc. I've seen those in Germany, Switzerland, and the US. Can confirm that they work in Western Washington, but they're for solitary "digger bees", not your standard honey bee.
> It’s no surprise that the region that gave birth to agriculture has also refined innovative sustainable agriculture methods for thousands of years. Pigeon towers were one such innovation—and they helped Persian farmers cultivate all kinds of crops on previously arid, thin-soil land.
Didn't ancient Persia originally have much more fertile soil, but unsustainable practices (like the introduction of goats) destroy the soil quality? I guess both can be true, initial poor practices necessitated the introduction of more sustainable techniques.
So? The N still has to come from somewhere. The natural sources of N (nitrogen fixing plants, NOx from lightning or natural combustion), filtered through the birds, will not come anywhere close to what synthetic fertilizers can supply.
As many as 80% of the N atoms in your body were fixed artificially by the Haber-Bosch process. Natural sources, using pigeons or not, are not up to the task.
Nitrogen fixation occurs naturally in the soil by bacteria. As the nitrogen is consumed by different species up from one trophic level to another, from plants to insects to bird, the nitrogen gets more and more concentrated.
Birds are fairly high up the food chain, and their excrements are very rich in various nutrients, including nitrogen, phosphorus and potassium.
The Haber Process is faster but requires a lot of energy, and provides no phosphorus or potassium, so you have to source it elsewhere. Also it requires no technology and can be installed pretty much anywhere.
I suspect that this can work for low intensity farming, like fruits and vegetables, but if you want to feed the cattle of the earth, you'll end up running out of pigeon food.
One of the best solutions to out fossil fuel problems is to simply have less people. We need to dramatically reduce the number of humans. Perhaps then the pigeons can help.
ps: I recommend we let current humans die of old age, and make less new ones. Not attempt to get rid of humans already here.
I'd phrase it as "reduce the number of mouths to feed". That way it could be achieved by reducing the amount of cattle grown for meat and we could eat more grains etc... ourselves instead of feeding those intermediaries.
Yes, nitrogen fixation occurs naturally. But the amount fixed is insufficient to achieve the yields of modern industrial agriculture on a global scale.
"Natural sources, using pigeons or not, are not up to the task."
Sure they are. Just not on the current scale (for the current processes and preferences). It raises an interesting question about how many people the earth can sustainably support though.
The article said that this has historically been used for nitrogen-demanding crops, so it must have some value.
"Pigeon towers became a crucial part of the agricultural economy, providing much-needed fertilizer for melons, cucumbers, and other nitrogen-demanding crops—cornerstones of Persian cuisine."
It’s bioaccumulation. There is some potential for them to be extracting phosphorous from the rocks in their gizzards, but that will mostly be bioaccumulation too.
They do most of the work... The N comes from Urea. When mixed with the soil and the rest of the bacteria-rich bird litter, it's exposed to various ureases to create NH3, which combines with water for NH4 which plants can use.
As for economical in the "traditional" sense, maybe not. I don't know how much success they're (still/actually) having but if you want a little glimpse into what should be possible in easily digestible docu-film format, look up "The Biggest Little Farm" (it's on Netflix for example).
One thing I took away from that is that it's maybe not economical in a "have a one crop pigeon poop farm" (i.e. you sell pigeon poop from feeding pigeons), you can have a farm that sells a lot of things that uses a lot of different animals and crops in combination in order to not have to buy in things from the outside that "traditional" farms have to.
I would be interested in seeing if that stays true in an increased number of niches, especially with fertilizer shortages and prices likely to play into the near future.
And that source gets it from? As I said, the natural nitrogen fixing processes are insufficient to supply agriculture for nearly 8 billion people. And that N is more efficiently used by exploiting the nitrogen fixing sources directly rather than by filtering it through pigeons. In no way are pigeons a substitute for artificial nitrogen fixation.
I largely agree with your sentiment: articles should educate, so it's important that the average reader ends up learning say in this case the dependency tree, i.e. knowledge that some species of organisms have the genetically coded skills to say fix nitrogen while others don't.
The problem is that for those who don't already know this, these article are typically not that educational, and that for those who already do, any potential advantage of these pigeon tower is not explicitly elucidated either.
For example I can come up with self-concocted explanations why this is senseless in the sense you describe: i.e. fundamentally the bird is not a nitrogen fixer, so it ate the fixed nitrogen compounds from which the compounds in its faeces derived.
On the other hand I can come up with explanations despite its not being a nitrogen fixer why it still might be a net positive decision: perhaps the land has some insect pests anyway (pigeon towers or not), so that having the pigeons around results in them eating predators of your crop, while recycling those predators into useful nitrogen compounds...
The problem is that I know its just a wild guess I make.
Ideally we would read an article and understand under which conditions the pigeon towers make a net positive versus a net negative.
I am not trying to take a dump on the article: I'd rather know such structures existed and know I don't fully understand when they make sense than to know nothing about it at all... understanding must start somewhere.
Something that stands out to me is that these structures look very time consuming to produce by hand, but the designs are well suited to 3D printing from concrete or similar materials. Though I don’t know if 3D printed concrete can accomplish “bridging” as is done with plastic 3D printing.
There was a 1856 law that encouraged US citizens to claim land for the country if there was bird poo on it: https://en.wikipedia.org/wiki/Guano_Islands_Act
This law is how the US originally got possession of Midway, which became very well-known during WWII (I always wondered how the US got it originally): https://en.wikipedia.org/wiki/Midway_Atoll