By 1973, The Humane Society of the Pikes Peak Region, like so many animal shelters across the country, had become quite alarmed at the numbers of animals being euthanized each day. The fact that an agency chartered in 1949 to provide animal relief and rescue had become a humane slaughterhouse, killing upwards of 50 animals each day, was appalling to the organization's directors, staff, members, and to the public at large. It was becoming apparent that the Society’s humane officers had become urban game wardens, routinely killing thousands of pets each year so that the rest could survive on limited resources. This is similar to the wild animal population control device called hunting. Though euthanasia is an effective population control measure, emotionally it left much to be desired, and it went against the grain of the Society's original purpose.
Arkow, Phil, "Animal Control, Birth Control, and Community Education: Impacts on the Colorado Springs Pet Population, 1970-1984" (1985). Management and Control of Companion Animal Populations. 10.