I am in the P.N.W. where we are blessed with a ton of different types of birds. The downfall to that is they love attacking new plantings and my fruits. What I've been using are recycled disco bulbs I picked up at the local Goodwill for $1.99 and $1.50 each. I split them each in two which gave me 4 halves, then I just put them where needed, on the ground or hanging on the fence.
The reflections on all of the little mirrors keep every bird, except my hummingbirds (there on a different mission) out of my gardens. It creates the neatest spots of light all over, like dancing crystals. It's been more than a bird repellent, it's a great eye catching display of beautiful rainbowed lights!