[toss1]

>>But ultrasonic animal deterrents are not without controversy.

>>The RSPCA has long-objected to them, stating: "Noise levels produced by such ultrasonic devices are likely to be aversive to some animals, potentially causing them discomfort, fear and/or pain and predicting an individual's response is difficult."

>>Mr Milward said he "recognises the importance of living harmoniously with wildlife" but just wanted a humane way of protecting his two young children from the mess left by foxes and badgers, while also preserving his garden.

Ummm, it seems that a small amount of discomfort, fear, and/or pain, all of which is easily escaped by the animal is exactly the point! It is called operant conditioning by negative reinforcement related to a specific behavior.

What it the alternative, hooking up the device to a water cannot, paintball gun or real gun; are those really better?