Canine population dynamics: a study of the Manhattan, Kansas, canine population.

Analysis of the age distribution in the pet population of dogs in the community of Manhattan, Kansas from 1968 to 1979 revealed that the distribution was stationary and the rate of population change (lambda1) was close to 1, which means, that if present conditions do not change, the population probably would remain stable in size in the future. The number of females spayed in the Manhattan population reached a frequency of 66% in 1979. Considering only present age-dependent birth and survival rates, the population could not maintain itself and would decrease rapidly in size. It was found, however, that the population is maintained by a high net rate of immigration, with about 75% of all dogs under 6 months old coming from outside the Manhattan population. The ratio of people to dogs in Manhattan was estimated to be 4.14:1; about 41% of all dogs under 6 months of age were acquired through breeders. Roaming animals in 1 year represented about 12% of the canine population in Manhattan; of those, 36% were stray (not claimed by owner) and the rest were owned and redeemed. The data represented only a portion of the population (dogs with responsible owners) and for a complete understanding of the dynamics of the entire population, one should analyze roaming dogs in a similar way. The methods described in this study should be useful for collecting data to be used by veterinarians and municipal authorities confronted with proposals for regulation dealing with reproduction and pet population.