Territorial Mockingbirds

A pair of mockingbirds have a nest somewhere near our house, and for the past week they've been terrorizing our dog Sheila and cat Pearl. It's gotten to the point that Pearl won't even go outside during the daytime. The mockingbirds divebomb her, and taunt her by hopping up and down on the ground right in front of her face, while chirping their alarm call all the while. Even Sheila, who is considerably larger than Pearl, is intimidated. If this is what it takes for them to defend their nest, so be it. I keep telling Sheila and Pearl that it won't last too much longer.