How about solar mole repeller?
The Solar Powered Mole and Gopher repellent works in the garden. And it also works on voles, shrews, and other destructive rodents.
The noise of solar mole repeller is silent to human ears, but it will prevent burrowing pests from tunneling your yard to death. The Solar Mole & Gopher Chaser produces a sonic pulse. You can use overlapping stakes to cover a larger area.
This solar gopher repellent repels unwanted burrowing rodents with the strongest and least expensive power available just because it's powered by the solar.
This ingenious device is environmentally friendly and eliminates the use of poisons and traps around your children and pets.
Pets won't be affected by solar mole repeller, but rodents find the noise irritating and eventually move to quieter surroundings