With its vibration similar to the feeling of an upcoming earthquake, ultrasonic mole repeller always creates a “false alarm” for the mole. Besides, the signals emitted by the mole vibration devices are not distinguishable to the human ear and are only captured by the more sensitive ears of animals living underground, causing them a sense of discomfort, which is why the animals leave the site. However, it won’t harm or affect your dogs or cats as the sensitivity levels of moles and your pets are different.