Because of the short pregnancies and large litters of dogs and cats, one individual female with all her female offspring reproducing similarly can be the source of over 4,000 new lives within seven years. Some of these animals will find homes complete with laps to sit on and fireplaces to enjoy, but millions of other perfectly healthy dogs and cats won't be so lucky. The overabundance of these potential pets tends to cheapen the intrinsic value of each individual animal in the eyes of the general public. The swelling problem causes some people to use cruel methods of disposing of unwanted pets, such as abandoning them along highways, or drowning them, regardless of the availability of an animal shelter.
"Solving the Pet Overpopulation Problem" (1983). CUP. 27.