Oda said a humane killing would be any method that caused the least amount of suffering. Shooting is singled out as an acceptable method in his bill, but Oda said other means that would be allowed include using a bow and arrow, clubbing or decapitating some animals.
Feral animals are typically domestic species that are wild, such as cats and pigeons. They can pose threats through infection and predation to other animal populations, Oda said. Killing them quickly is often the best control method, he said.
"I want to protect people from getting in trouble for doing the right thing," Oda said.
No-kill methods, such as relocation or catch, neuter and release, are less efficient and more expensive, Oda said.
The Legislature passed a law that made animal cruelty a felony in 2008, after almost three years of lobbying by advocates.
Anne Davis, the Animal Advocacy Alliance of Utah's executive director, said feral animals were intentionally protected by that law.
Davis said there is no humane way for people to kill feral animals. To control populations, the animals should be fixed so that a feral cat colony will eventually disappear.
"I don't think shooting an animal is ever humane," Davis said.
Rep. John Mathis, R-Naples, the House sponsor of the 2008 law and a veterinarian, said the primary intent of the law was to protect pets from abuse. As for feral animals, he said sometimes they needed to be killed, especially when they can't be caught or they carry disease.
Mathis said the American Veterinary Medical Association provides guidelines for humane euthanasia that he follows.
Those guidelines include shooting, blows to the head and decapitation, but they emphasize the killings should be done by properly trained people using well-maintained equipment. Decapitation is primarily recommended for a research setting.
Gene Baierschmidt, executive director of the Humane Society of Utah, said the change could allow people to kill feral cats indiscriminately.
"It would allow people to go to a feral cat colony and kill all of them," Baierschmidt said. "It's an archaic bill."