PETER THEOBALD says: Obviously, the more accurate the colouring of artificial decoys, the better, but painting it a different colour is unlikely to make a major difference. Even real pigeons look different in various light conditions.
What IS important is creating movement within the pattern, and as you say, whirlies go a long way to achieving this. In winter, when food is likely to be scarce, pigeons rely heavily on keeping in flocks to locate the field where their pals may be congregating.
The flash of white as a woody lands is what signals all is well to following birds. Rotaries and flappers replicate this movement perfectly ? and it can be seen from a long way off by other pigeons.
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