We should all know by now that corvids (ravens, crows, etc.) are amazingly smart animals. But this is a new one on me. Amusing Planet gives a brief report and some nice photos of how crows in Tokyo make their nests using anthropogenic material. Indented prose is from the article:
Food isn’t the only motivation factor that drive crows to adaptability. Crows also demonstrate intelligence when building nests, using whatever materials that are available to construct them. A typical nest is composed of interlocking twigs, often recycled from the old nest, and pieces of wires of various lengths and thickness, gathered from the surrounding, to strengthen the nest structure. Tokyo residents have observed that crows in the city have learned to use coat hangers instead.
Photo from Goetz Kluge:
In such a large city, there are few trees, so the natural materials that crows need to make their nests are scarce. As a result, the crows will often steal hangers from the people who live in apartments nearby, and carefully assemble them into intricate nests. The completed nests almost look like works of art.
Photo by Badaunt:
Nests built from hangers were also discovered in other Japanese cities. In Fukuoka City, the Jungle Crow would often make nests atop power lines during the breeding season that could cause large blackouts due to short circuiting. The Kyushu Electric power company actually has “crow patrols” that search out and destroy hanger nests on their power grid.
Photo by Brian G. Kennedy:
I seem to recall that my friend Amy, our erstwhile Japanese Correspondent who has vanished, told me that in Yokohama that crows would rip open garbage bags to steal the hangers.