How do starlings drcide how many feed in any particular place...food is not limited at our bird table but only 6 or so feed hrrh each day out of 1,000s that fly past.
I don't think anyone can give a definite answer but I think you want to be thankful, I can get over 100 and they can be noisy and could be a problem for your neighbours.
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I suspect it's just a case of the local starlings visiting your feeders as they're probably used to eating supplementary food, and the continental starlings sticking to what they're used to out in the fields.
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