Can you borrow a neighbor's dog for a few afternoons? We had a similar challenge until we got our Golden Retriever. He never chased them but his smell/presence & marking his territory was enough to help them move on...to our neighbor's.

I can relate and what has worked for me is the live trap Have-A- Hart (2 door style) and using a small bit of peanut butter inside the trap. I tend to put the trap where I see them running back and forth from or where they hang out (like under the bird feeder- yeah, I know I'm attracting them!). Release at least 2 miles from your home as any closer they have a knack of finding their way back- so I've been told! Clean the cage after each use. I use 2 traps at the same time in different areas. This is my 3rd yr of using them and I'm finally down to seeing one or two now and then.

My greyhound took care of the chipmunks in my gardens.

A cat or dog.

Doh. A Greyhound is a dog.