For about 4-5 weeks now, my Blue Jay and squirrel population has dwindled to barely anything, when it used to be I couldn't count the number of each. I've also just lately noticed that there are hardly any cardinals either. The only two things I can attribute this to (and the first is very iffy) is No. 1) I moved 1 bird feeder pole to another area (due to soft, sinking earth) with the flat plank on the stump remaining there, from which the blue jays, cardinals, and squirrels ate nuts and seed; or No. 2), we have had visits from a hawk (I'm pretty sure a Cooper's), who has killed and taken two mourning doves. Now, what's strange is we have had a hawk in and out of our yard for the past several years - it has never relocated our bird or squirrel populations. And I did think that maybe there is an over-abundance of naturally occurring food right now, but again, this can't be the only year that there is, as I've fed birds and squirrels here for the past 12 years, with this current mystery never happening. It has gotten so weird, that come the next morning, I am still seeing peanuts at feeding places, untouched, as well as SHELLED peanuts! Some of the bird feeders are often untouched as well come morning. The peanut brand I buy is the same (unsalted, of course), and the bird seed brand is the same few we've always used. The sparrow and goldfinch population, chickadees, nuthatches, woodpeckers and titmice, are all looking about the same, population-wise. But this eerie, "no flock of blue jays dive-bombing for the peanuts" and "no squirrels playing on the tree trunks" mystery is disheartening. I can hear blue jays sometimes calling, and I'll see one in the yard grabbing a peanut, sometimes catching a drink at the birdbath (clean water always), but the flock is gone. Any ideas, anyone? I miss my jays and squirrels terribly. They used to come running/flying to the sound of me tossing peanuts! It was my daily morning routine, before filling the feeders. Can one Cooper's Hawk cause this disappearance?