[São Paulo Pasteur Institute Technique for estimating a canine population]

This paper describes a technique developed by the Pasteur Institute in São Paulo, Brazil, for counting and classifying a canine population according to levels of dependency and confinement. First, a household survey was performed to identify dogs with owners and their degree of restriction. Different-colored collars were given to totally and partially restricted dogs. Dogs cared for by individuals who did not consider themselves the owners received collars of a third color. After the survey, surveyors counted and recorded dogs on the streets according to the color of their collars. Absence of collars identified dogs without owners. Surveyors were positioned at predetermined sites, an average of 50 meters apart. Counting time lasted 30 seconds and was repeated every 10 to 15 minutes for one hour, with starting and finishing times signaled by blasts on a whistle. The technique was used in the city of Serra Azul, São Paulo, Brazil, by 13- to 17-year-olds after a one-day training program. A total of 498 dogs were recorded in two census tracts, 5% of which were classified as without owners and unrestricted.