Many of us experienced our gardens invaded by large flocks of crows, ravens, or similar birds. They tend to dominate bird life in such areas, reducing overall garden biodiversity.
In my case, crows have moved into our neighborhood big time, and they're monopolizing our bird feeders (plus making a mess on my car). Any suggestions for how to discourage the crows without scaring away the other birds (finches, cardinals, nuthatches, the occasional woodpecker or hummingbird). (Though if I can also discourage grackles that's a plus.)
I'm thinking something like a sonic unit that broadcasts a crow distress call, but the units I find online are 1) pretty expensive, for the most part, and 2) poorly documented -- not clear whether they can be set up to broadcast ONLY adult crow distress calls, vs more general calls or juvenile distress calls that are intended to attract prey.
I'd also like something (if it's an "active" scheme of any kind) that I can turn on and off, activating it only when crows are observed.
(I'm not a birder, but, based on the Wikipedia article for "American crow", the birds I'm dealing with match the appearance and call ("caw-caw-caw") of Corvus brachyrhynchos.)
Images from the next town over: