SHANGHAI -- Raccoon dogs are ballooning in number and expanding their habitats in the eastern metropolis of Shanghai, a new survey on the crafty urban dwellers has shown.

Shanghai is home to about 25 million people and thousands of wild raccoon dogs, a state-protected mammal that roams the city's streets and residential complexes like weasels in Beijing and foxes in London.

The latest study, conducted in the Songjiang district, found the animal in 22 out of 50 residential complexes, with the number ranging from 1 to 50. The average number stands at 10.82 for a raccoon dog-inhabited compound.

Their population in the city is estimated to be between 3,000 and 5,000, said Wang Fang, a researcher with Fudan University, which conducted the study with the Shanghai Forestry Station and the Shan Shui Conservation Center.

The density of raccoon dogs is related to neighborhood management. Improper feeding of stray cats and random disposal of kitchen waste, for instance, will double the number of raccoon dogs in the residential area, according to the study.

The financial hub in east China was once the native home to many mammals like leopard cats, badgers, and Siberian weasels, many of which have lost their natural habitats amid rapid urbanization.

Raccoon dogs, however, have adapted to the urban environment and are rapidly increasing in population, Wang said, adding that their number also benefited from the city's expanding green space, including wetlands and parks.

In recent years, the critters have been more frequently spotted by local residents, sometimes gripping local news by engaging in fights with pet dogs.

The study will inform local authorities in finding ways of harmonious co-existence between city dwellers and their wildlife neighbors, said Zheng Yunxiang with the Shanghai Forestry Station.

"Reducing feeding behaviors and proper disposal of kitchen garbage are important to controlling the raccoon dog population in residential areas and avoiding conflicts between residents and raccoon dogs," Zheng said.