In London, they do not carry messages like their cousin "travelers" but pigeons are equipped with a small electronic box which records their location and data on quality of air.
Certainly, fixed sensors are already present in the British capital, but pigeons can cover a larger area and go higher in the sky. Survey results are then processed and tweeted on the Twitter account of the "air patrol" of 10 pigeons.
According to a report on the website RT, users can send a tweet with their position and receive in response an indication of the air quality in their area.
Launched last Monday, this new operation will last a total of three days. The pigeons are not however, only tweeting, but an application for smartphones and tablets has been designed, and a website too.
The aim is to sensitize the London air quality because, according to the latest research, the pollution causes 9,400 premature deaths per year.
After pigeons, a beta testing is envisaged with 100 people (cyclists, runners, walkers) who will benefit from the same equipment.