To answer the question in the title I am going to rely on a very substantial survey from the United States conducted in the late 1990s from the Regional Shelter Relinquishment Survey Study. It was a team effort between the National Council on Pet Population Study and Policy and researchers at four American veterinary colleges: Colorado State University, Cornell University, the University of California and the University of Tennessee.
The study
It was conducted by a group of scientists led by Salman and published in 1998 according to my source which is PH Kass in his contribution entitled Cat Overpopulation in the United States as published in The Welfare of Cats, an excellent book, edited by Irene Rochlitz. That is a very lengthy introduction but I wanted to get the referencing absolutely correct.
Spreadsheet listing the reasons for relinquishment to shelters in the USA
The spreadsheet below lists in descending order the reasons given by owners for the relinquishment of their cats to animal shelters. The percentages refer to the number of individual reasons for relinquishment divided by the total number of reasons for relinquishment.
I would like to add some words. PH Kass tells us that “the most common classes of explanations for relinquishment of cats were issues related to human lifestyle” i.e. health and personal issues. These caused 35% of the relinquishments (abandonments). Issues relating to human housing represented 26% of the reasons, cat behavioural problems but not including aggression towards animals or people represented 21% of the reasons, the household animal population (15%), owner preparation for and expectation of pet ownership (50%), request for euthanasia for reasons unrelated to age and illness (12%). There were other classes of explanations but they were less frequently reported.
Type of cat given up
The characteristics of the cats surrendered to shelters were checked out. Only 8% of the cats abandon to shelters were kittens, 40% were in the age range five months to 3 years, 23% were between 3-8 years and 14% were older than eight years (age was unreported on 16% of cats).
Male or female, sterilised or not
A higher percentage of female cats (59%) were relinquished compared to male cats. About half the cats were sterilised and about half were not sterilised (I find that statistic extraordinary). This may explain why cats are relinquished because they are unsterilised.
Purebred or random-bred, indoor cats
Almost 93% were non-purebred cats. About 83% of the cats hardly ever went outdoors or never went outdoors. They were essentially full-time indoor cats.
Adoption sources
The cats were adopted from a variety of sources. The main source of adoption was a friend who previously owned a cat (33%), a stray cat (23%), an animal shelter (14%) and the offspring of the owner’s pet at 9% of occasions.
Length of ownership
The cats were cared for by their owner before they were abandoned to a shelter between 7-12 months (30% of respondents), more than five years (19%), between 2-5 years (15%), 1-2 years (16%). Only 5% owned their cats for less than seven months and in 15% of cases the length of ownership was unreported.
Some Comments
I would just like to make one or two comments about the study’s findings. You will note that “too many cats in the home” as the number one reason. This points to multi-cat homes and hoarding which is a stage beyond multi-cat homes. Obviously, this points to human carelessness and bearing in mind that about 50% of the cats abandoned were unsterilised you can see the connection. Human carelessness leads to not sterilising cats. This leads to procreation which leads to unwanted cats over time.
Being someone cynical, I would suggest that if a person abandons their cat to a shelter, one reason that they may give in order to avoid embarrassment is that they are allergic to cats. “Moving home” is another at least potential excuse and not the real reason.
The story behind all of these reasons is human behaviour. I think that harsh point needs to be made. If you analysed each reason, you would trace the ultimate cause back to human behaviour in every instance.
I expect the reasons that exist in America to be similar to other countries in the developed world.