The Dutch were the absolutely best at it; the English romantics, next best. Apparently in those days they actually saw a lot of raptors circling above because their birds look real. They look real, for one thing, because there is perspective, that is all the birds are not the same size. They are actually in space , near and far, not looking like they were painted on a sheet in the background. There is usually more than one bird and they are not all in the same place. You see one or two at tree level and then some high in the sky. If there’s a grouping, they extend in space by some getting smaller.
The worst cliche is the single, dark, thick V in the sky. Birds have bodies and heads that can’t be that prominent at far distances, but the Dutch knew how to at least indicate them. Also birds at the usual distance from us in the sky are not deep black. They are gray. If there are more than one V, they are usually too close together or in some very geometric form like a line.
These birds (vulture, hawks, buteo, etc.) in the sky are using updrafts to soar effortlessly. An example of an updraft is a wind that is being deflected by a hill so that it is blowing upward. Updrafts can also occur when the ground is being heated by the sun. The birds have to stay in the updraft, so they are soaring in fairly tight circles and therefore tilt their wings like an airplane banking. Some are at the bottom of the updraft and some are near the top. When a bird reaches the top of an updraft, he or she can glide down to the next one sometimes miles away. This means that birds are more likely to have some vertical arrangements rather than linear, and there can be two vertical arrangements separated by quite a lot of space.
I guess this problem with depicting birds in the sky illustrates John Ruskin’s wonderful remark that the first rule of art is that you must only paint what you see. He went on to say, thinking of Blake, that, if you see angels, you can paint them, but, if you don’t see angels, don’t try to make them up. (Blake, since he was a child, claimed to see angels). So, if you haven’t really looked at birds (or angels, I guess) in the sky, do that first before putting them in your paintings.
In this fragment of a little colored drawing by John Sell Cotman, the birds are nicely arranged in two group, one obviously nearer. The second group has got an updraft which keeps them together, but even then there seem to be two smaller birds that are on the far side of the updraft.
Here’s a Dutch sky with birds by Hercules Seger (that’s how he spelled his name) or Seghers. That’s how to do it.
Of course, the bird we see today is the pigeon, or more official the Rock Dove. It doesn’t really live in the sky in the same way that the birds, for example, in the Seger above do. It flies from place to place as fast as it can, and it is, in fact, a fast bird. One bird will zoom by at 40 miles an hour. A flock that is somehow flushed off a building would be really difficult to paint and compositionally distracting. It is more a bird to put on the ground than in the air.
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