This of course brings them into conflict with us, because we want the garbage to stay in the bags. In Tokyo I have noticed several methods to try to deter the crows. "Scarecrows" are not new and crows are smart birds, probably the smartest, they know what we're up to. Bits of shiny plastic, human shapes with arms akimbo, noisemakers, the crows have seen them all before and worked out that they pose no threat. A small boy walking up and down the field throwing stones and shouting will certainly get their attention but, 'stone the crows!' is that the best you do?
So someone has tried a little crow psychology. Remembering that crows are the smartest birds in the world, a smart Japanese man has used his intelligence against them. His I scarecrow' is a dead looking plastic crow, wings half sticking out, hanging upside down inside a square net bag. This is then hung above the garbage bags. The crows stay away. And why? Because the crows see one of their own dead in a net bag and they don't like it, so they stay away from that place of potential danger. Meanwhile the dumb pigeons are quite happily picking at crumbs right under the hanging crow.
We human beings are very intolerant of other living things invading our space. We will not share our homes, cities or fields with other species unless they have been specifically invited. Invaders are trapped, poisoned, stamped on, dug up, or scared away. But crows have been living with us (and on us) for thousands of years and no amount of scarecrows will ever scare them away.
Crows are tough, resourceful survivors. Their range covers almost the entire globe. Only South America and Antarctica lie outside their natural domain. They occupy every conceivable environment from the garbage dumps of Reykjavik to those of Timbuktu in the Sahara. They can be found at the bottom of the Dead Sea valley and up over 6,000m in the Himalayas, while their close cousin, the Alpine chough, has followed mountaineers for scraps at 8,000m. I saw these birds myself while trekking in Nepal in 1998. Up at nearly 6,000m, with no vegetation or any signs of food, they were swooping and diving in the cold, clear air, or watching us from a safe distance, waiting for some dinner.
The key to their success is their adaptability and their ability to exploit human resources, from eating refuse to preying on livestock and crops. But they can also catch fish by plunging head-first. They knock holes in trees like woodpeckers. In the high Arctic after watching human fishermen pull fish through holes in the ice, a group of crows started doing the same when the fishermen retreated to their shack for coffee. The crows actually pulled up the lines leading down the holes, then devoured the fish or bait they found on the hooks.
We persecute them because they steal our livestock and crops, but we hate and fear them more because they Pick clean our own remains. Crows have cast their shadow on human bones since the origins of human kind, 4 million years of intimacy that has made them the most mythologised of the world's birds.