Hot pepper added to sunflower seed has barely slowed squirrels from feasting at our birdfeeder. This redtailed hawk will do the trick, but unfortunately, birds are the hawk’s intended prey, so none will come close.
Photos are poor quality taken through kitchen windows. With the feeder only thirty feet from the house, the hawk would flee with even a sudden movement from inside the house. The squirrel understood the danger in approaching the feeder, but was compelled to test the limits. Each time the squirrel moved closer, the hawk jerked its neck and the squirrel fled. 
After several minutes, the hawk realized the futility of hunting from this perch, so it flew off to find higher ground.
Ramblin' through Dave's Garden 
My sweetheart recently put out a ‘squirrel proof’ bird feeder in his garden. Within two days, the small garden seemed full of squirrels, all effortlessly able to get the seeds. I counted five at one time. A stray cat was attracted too and took up position by the bird feeder, waiting for an unwary lunch. Sadly the bird feeder had to go.
Before treating seed with pepper sauce, I figure that squirrels consumed 80% of seed. After treatment, less than half, and of five recognizable squirrels, I think that only two continue to feed. My little research project continues with trialing safflower seed next week.
Do the birds not mind the pepper?
No. Writing about squirrels triggers a wealth of helpful information. Mammals, to varying degrees, will be effected by pepper flakes, seeds, and sauces, but not birds.
And today is “squirrel appreciation day”! How appropriate.
Today, the hawk appreciated that the sunflower fattened squirrel was too large to carry off for dinner.
Great photos!