I was thinking of how to incorporate bird skull stencils into my window bird-strike preventers, and this is the happy result! Instead of crossbones, I added crossed feathers right below each bird skull. Latin phrases in a stencillized pirate font spell out the danger and allow air flow.
The reason we hang feathers to deter birds is that the presence of feathers signals danger to a bird, and they tend to veer away from such feathery places.
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