The coming census, which will involve municipal employees knocking on doors and asking residents about their pets, has some of them angry or anxious, The Detroit News reported.
"They definitely have ulterior motives," Phil Brooks, 22, said. "I think they're just doing it to see what's where and to be Big Brother. But it violates our right to privacy.
Brooks, who owns a dog, said the city appears to be taking no interest in counting cats. He believes the census is aimed at tracking pit bulls.
City officials said 32 people were bitten by dogs in 2012 and half the animals did not have licenses.
"It's about one, making sure they're vaccinated; two, it's a means to return lost dogs, and three, it's putting the city in compliance with state law," Don Johnson, the city manager, said of the census.
The census begins July 1. Owners of unlicensed dogs will be fined $20 and face much stiffer penalties of up to $500 if they fail to obtain a license within two weeks.