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  • Writer's pictureSusan Houser

The Historical Role of Spay-Neuter in No Kill

Back in the 1970s it was not common for people to have their dogs and cats sterilized, and it was common for people to allow their dogs and cats to roam as they pleased. This resulted in a lot of dogs and cats. Shelter intakes back then were about 5 times higher than they are today. Shelter statistics from those days are sketchy, but our best guess from the available evidence is that the situation for homeless pets reached a crisis point around 1970 due to their massive numbers.

Killing was the default solution that shelters used for the overwhelming number of animals they received. The Lane County shelter in Eugene, Oregon, was receiving 100 animals a day, for example, even though animal control officers did not take in cats. Shelter intake in Lane County today is a tenth of that number or less. Shelter intake relative to human population back in the 1970s was about 110 per 1000 people, if not more. By comparison, average shelter intake today is estimated to be about 22 per 1000 people.

But the number of animals coming into shelters was not the only problem. An even bigger problem was the number of animals that were in the streets, that shelters did not impound. For example, James Child did a study on cats in the early 1980s and found 725 to 1813 free-roaming cats per square mile in one northeastern city. If you wanted a cat or dog in the 1970s all you had to do was wait, and before long you would hear of a friend, neighbor, or relative who had a litter of puppies or kittens to give away. Or you would see someone on the street hawking free or very cheap puppies and kittens. Or you might find a litter of feral kittens in your backyard, or be adopted yourself by a homeless stray. There was no need to buy a dog or cat unless you wanted a particular type of purebred, and there was no need to go to the shelter to adopt because animals needing homes were in your neighborhood.

Could shelters have saved all of their animals in the 1970s? Of the No Kill shelters I’ve studied, the ones that have intake per 1000 people of 40 or 50 or more generally seem to use transports a lot, or adopt animals to people outside of their own jurisdiction, in order to get to a 90% or better live release rate. In the 1970s all the jurisdictions were full of animals, so transports and out-of-area adoptions would just take homes from other homeless animals. Shelter workers in the 1970s were not enthusiastic about adoptions generally, because with so many animals needing homes, finding a home for a shelter puppy meant only that another puppy was left out. Adoptions in the 1970s were like a giant game of musical chairs, with not nearly enough chairs. A shelter adoption just meant that a different animal was left standing.

In order to save all animals who were admitted to shelters in 1970, one out of every three people who currently owned a pet at that time would have had to adopt another one from a shelter. Then in 1971 another one out of three would have had to adopt, and so on. And with shelters putting intact animals into the environment (because back then shelters did not have the veterinary support to spay and neuter all of their animals), the pet overpopulation situation might well have gotten even worse. In a world where most dogs and cats were intact and a high percentage of them were free-roaming, shelter killing was about the only means that communities had to contain pet population.

Shelter killing did not keep homeless dog and cat populations from growing, but it probably did make them grow more slowly than they otherwise would have.

Could shelters have simply left animals on the street rather than taking them in only to kill them? In the 1970s, many shelters, perhaps most of them, did leave cats in the street. Cats were typically considered free-roaming and were not impounded except in cities where residents considered them to be nuisances, or public health officials considered them to be health threats. As to leaving dogs in the street, or leaving cats in the street in the cities where they were considered to be nuisances, it is doubtful that citizens in the 1970s would have tolerated that approach. A survey that was done in 1973 of city mayors found that animal nuisance complaints were the number-one complaint that mayors received on any issue. In 1970 there were very few spay-neuter programs and veterinarians did not routinely recommend that people spay and neuter their pets. At that time veterinarians were just getting adjusted to new technologies in anesthesia that made spay surgeries safer than they had been in earlier decades. Very few if any veterinarians were doing pediatric spay-neuter in the 1970s, and even people who did get their dogs and cats spayed often did not do so until after their pet had had a litter or two.

That is a very depressing picture. Shelter workers who loved animals and did not want them killed faced options in the 1970s that ranged from bad to worse. So what did they do? They started a gigantic spay-neuter campaign. Today we tend to be bored with spay-neuter. We hear about it all the time, and sometimes it seems as though the “spay-neuter” mantra is just being used as an excuse not to put programs in place to get animals out of the shelter alive. But in the 1970s, the spay-neuter campaign changed the culture, and changed the world for homeless pets. We went from a country where only a minority of people sterilized their pets to a country where more than 80% did.

And at the same time people began to value their pets more. That probably was not a coincidence, because the spay-neuter movement included an educational component to encourage the idea that the lives of cats and dogs had value.

By the year 2000, shelter intake had plummeted by close to 70%, at the same time that the number of owned pets had more than doubled. If you look at shelter intake in 2000 relative to the number of owned pets, it had declined almost 90% since 1970. It was not the spay-neuter clinics themselves that did all those spay-neuter surgeries – what happened was that the free and low-cost clinics that were popping up all over in the 1970s inspired the veterinary profession to start to recommend spay-neuter as a routine part of health care.

Even more important than the startling decline in shelter intake was the decline in homeless, free-roaming dogs in the environment. By the year 2000 feral and homeless dogs (as opposed to dogs who had homes and had strayed) were down to a miniscule number in most places, and continued to be a problem only in a few large urban areas and a few very rural areas. The number of homeless cats stayed high, possibly due to migration back and forth between the domestic and feral cat populations. But in the 1990s TNR became common and it offered a way to control community cats and reduce their nuisance behaviors.

The decline in shelter intake, the decline in the number of dogs in the environment, and the growing acceptance of TNR were the factors that made No Kill theoretically possible. The growth of the internet, particularly Petfinder, and the groundbreaking work of shelters like the San Francisco SPCA made it possible to implement No Kill as a practical matter. The first No Kill communities appeared toward the end of the 1990s in San Francisco, New England, and the Denver metro area, plus many small communities in Colorado and one in Michigan. In order for shelters to increase their live releases, they had to have a “market” for their animals. The disappearance of homeless dogs from the environment allowed shelters to adopt out dogs to people who otherwise would have acquired their dog from an unwanted litter in the neighborhood or by adopting a stray. TNR provided an alternative living arrangement for cats where they would be tolerated and even supported in the environment, thus increasing their market as well. The number of adoptions from shelters and rescues went up from about 5% or so of intake in 1970 to over 40% today. This appears to have been largely due to the disappearance of “competing” animals from the environment.

It is no accident that the No Kill movement started in the early 1990s, because it was at about that time that the pet overpopulation crisis had abated in the most progressive communities. In less progressive communities – those where spay-neuter rates lagged, and TNR was not in use – No Kill has taken a little longer to get a foothold.

In thinking about this history, what stands out to me is the massive effort on the part of thousands, if not tens of thousands, of people who devoted a great deal of their time and effort to change the tragic situation for homeless pets. In the 1970s this army of people worked on spay-neuter efforts. Beginning in the early 1990s, with the pet overpopulation problem having been greatly reduced in many places, the army began to work on increasing live releases. No Kill, more than most movements, is made up of lots of individual heroes. It is a true grass roots movement. As Rich Avanzino would say, the founders of No Kill were the American people.


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