Friend of mine had something like this to get rid of pigeons, Corvids and squirrels.
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I couldn't agree more. Squirrels are just fury tree rats with good PR, but given the opportunity they will do immense damage. They once got into my (old) shed and stripped about 15in of PVC insulation of a 2+E mains cable without any damage to themselves. They also east birds eggs, young birds in the nest and even small fully grown birds. If you ever catch one in a cage trap and then pick the cage up (by its handle) the squirrel will go mad trying to get at you or out - that's why there's a metal plate around the handle mount to protect you!
The only other bird we find annoying are Starlings. They are intelligent birds but they will come and raid your feeders in gangs!
We are lucky. We get every finch you can think of - including the most beautiful pair of Bullfinches and a group (maybe 6-8 at a time) of Goldfinches - a wide variety of Tits including a family of 6 long-tailed, Nuthatches, Robins, a Wren, a pair of Collar Dives, two pairs of Wood Pigeons, and an occasional visit from a GS Woodpecker and his family. Magpies are around but mainly away from the house, plus the usual Blackbirds and Jackdaws. If it helps steer them away remember that Magpies (which rarely venture more than about 1Km from where they were born) pair for life, as do pigeons, and doevs, so scare one and you will loose a pair.