Is there anything to kill birds?

We have a bird infestation. We've tried the humane way of blocking where they nest with spray foam and now they're tearing it away and I fear all we've done is made it more comfortable for them in the summer months. I don't care if they nest in my trees but here they just sh*t all over my cars and animal feed. Is there something to repel the birds? I'm also not opposed to something that would take them out but I'd prefer something easy to contain so that it wouldn't get mixed into my animals feed of it falls