Parks in Shanghai are being overrun by alien species, says the Shanghai municipal gardening administration bureau after inspecting 18 parks in the city.

For example, bird observers found Styan's squirrels in Gongqing Forest Park and Zhongshan Park and red-eared sliders in Xuhui Park and Kangjian Park.

Red-eared slider turtles, a species said to originate in Brazil, are an internationally recognized ecological invader. They grow quickly and survive easily, according to Professor Li Yingsen from Shanghai Maritime University.

They also reproduce in large numbers and can snatch food from native turtles thus threatening their existence.

These turtles were widely seen in a scenic spot in suburban Shanghai where visitors are encouraged to buy the animals and free them in the local river.

"Those superstitious people used to buy many turtles and other animals and throw them in public waters, such as the Yanzhong Park," said a turtle seller at Wanshang Flower and Birds' market in downtown Shanghai.

"You see many turtles in the park when the weather is fine," the turtle seller said.

Styan's squirrels, rarely seen in Shanghai, are occasionally now seen in public parks, most of them former pets capable of destroying trees, the report said.

Shanghai also is not home to azure-winged magpies, now found as strays or outdoor pets in the city.

Animal invaders

"Foreign animal invaders may not be a problem yet but foreign plants do pose a more serious threat. You can find growth spree of an American grass (Smooth Cordgrass) in Shanghai's only two natural reservation areas and we are supposed to reserve the areas in their natural state," Zhang Liquan from the Biodiversity Institute of Fudan University told China Daily.

He suspected few of the pet animals would survive or be a threat. There are other furry and slimy aliens in the city.

Rabbits from the Netherlands and Belgium, frogs from the United States and parrots from South America can be found in Shanghai's flower and bird markets.

These animals, often considered odd pets, are sold at lower prices than cats or dogs. Red-eared slider turtles are sold at 10 yuan (US$1.3) a pair.

"The government has regulations on import of foreign animals," Zhang said, "but that doesn't mean all imported animals are safe."

The report urged people who no longer want their pets - either because they're tired of them or the pets got too large to handle - not to abandon them in public.

(China Daily April 10, 2007)