The American Society for the Prevention of Cruelty to Animals says as many as 150,000 dogs are bitten by venomous snakes each year in the United States. There are also classes from Illinois to Florida to guard animals against eastern diamondbacks, timber rattlers and other venomous snakes. Like Belcher, most trainers insist that the use of the electronic collar is necessary to ensure a dog will avoid poisonous snakes. He acknowledged the growing debate about the use of electronic training collars, a method that the American Humane Society has opposed as cruel. Venomous snakes exist across the U.S., with various rattler species not only in the West but as far east as New York and North Carolina.