MADRID, May 8 (Xinhua) -- The Spanish birdlife charity SEO Birdlife began preparations for World Migratory Bird Day on May 12 by tagging three peregrine falcons, a species which serves as a barometer for an ecosystem's health.

According to the SEO Birdlife, the three falcons have been reared in a nest at Madrid's Hospital Central de la Defensa Gomez Ulla and will wear a ring on one of their legs, which will show all of their movements.

"A peregrine falcon may seem out of place in an urban setting, but it is part of the city's patrimony. If there is no wildlife around, it means we are also in trouble ourselves because these birds are a perfect indicator of an ecosystem's state of health," SEO Birdlife's Juan Carlos del Moral told Xinhua.

Del Moral explained that peregrine falcons are territorial and that when the three youngsters have grown they will have to move elsewhere. "In that way they will go to other provinces to breed and as they have grown up in a city, they will tend to breed in an urban setting," he commented.

He said peregrine falcons are at the top of the food chain and therefore affected by what happens to the birds that serve as their prey.

"If they disappear, it is because there are pesticides and herbicides and that in turn is a threat to humans as it will mean we have more health problems such as cancer," said Del Moral.

SEO Birdlife have created a project named Proyecto Migra aimed at protecting migratory birds, many of whom use Spain as a bridge on their yearly flights between Africa and the north of Europe.

The project will be carried out on a national and international scale, with the aim of tagging hundreds of birds in order to follow their movements and the coordinator of the project, Ana Bermejo, the project's coordinator, explained.

She said the tagged birds can easily be tracked, and blood samples will be taken from them.

"The problem in Spain is the pollution, whereas in the countryside they have predators, and also the danger of colliding with electricity cables or even wind generators," Bermejo said.

"All countries need to work to manage and protect these creatures," she told Xinhua.