Live rats are being trucked from central China, suffering a plague of a reported 2 billion rodents displaced by a flooded lake, to the south to end up in restaurant dishes, Chinese media reported.
Rats had been doing a roaring trade thanks to strong supply over the last two weeks, the China News Service quoted vendors as saying.
"Recently there have been a lot of rats... Guangzhou people are rich and like to eat exotic things, so business is very good," it quoted a vendor as saying, referring to the capital of Guangdong province, where people are reputed to eat anything that moves.
Some vendors, who declined to reveal their names, had asked people from a village in Hunan province, near Dongting Lake, to sell them live rats, the Beijing News reported.
"The buyers offered 6 yuan for a kg, but as to where they will sell the rats, they would not say," the newspaper quoted a local resident, adding that villagers had to catch the rats alive.
"If we want to do that, there is no problem. We could catch 150 kg of rats in one night... but we will not do this against our conscience," the villager was quoted as saying.
Some Guangdong restaurants were promoting "rat banquets," charging 136 yuan ($18) for one kg of rat meat, the newspaper said.
But the restaurants denied their rats came from Hunan.
Local governments in Hunan have been grappling with the rats, which had already destroyed 1.6 million hectares (6,200 sq miles) of crops.
A lack of snakes, also a popular dish in the south, and owls, a traditional Chinese medicine, was held partly responsible.
Chinese media reported last week that some Internet users from Guangdong had offered rat recipes as a way to deal with the problem.
Scientists have also blamed China's massive Three Gorges Dam project and climate change for the Hunan rodents' flight to dry land.