A theme park France has established a novel and environmentally-friendly way keeping its grounds free litter. It has selected and trained six "intelligent" rooks to pick rubbish and keep the park clean. Rooks are members the crow family and are to 47cm in length. The clever birds will be put to work the Puy du Fou theme park in the west of France. They have been trained to pick cigarette ends, paper and other things people throw the ground. The birds pick up the litter and deposit it into a special trash can, which then delivers some bird feed as a reward. The more litter the birds put the trash can, the more food they get.
The head the theme park, Nicolas de Villiers, explained the rationale using the crows to the AFP news agency. He said there were several reasons deploying the crows. He said: "The goal is not just to clean , because the visitors are generally careful to keep things clean, but also to demonstrate that nature itself can teach us to take care the environment." Crows are highly sociable and intelligent birds. Some biologists say they are as smart as a seven-year-old child. Mr De Villiers said: " an affectionate, supportive atmosphere, they like to communicate humans and establish a relationship play." The crows are speedy workers and can fill a bucket rubbish less than 45 minutes
