Russian museum has a team of cats to protect artwork from rats

A museum in Russia has employed a team of cats to protect the art work from the near by rats.
This ides is truly innovative read the story:  

There is a secret pack of security cats prowling the attic and basement of the State Hermitage Museum in St. Petersburg, Russia.

The museum administration has been hiring these expert rodent exterminators ever since the museum was founded in 1764. These cats have made it so that rodents cannot damage the museum’s artwork.

At the time of the siege of Leningrad (now St.Petersburg) during the Great Patriotic War of 1941-1945, many of the starving citizens ate all the cats and as a result, the city was infested by rats and the museum suffered greatly. As soon as the blockage was over, two cat-carrying carriages arrived in the city.

Now, each of these cats carry around a passport with a photo certifying that he/she is qualified to take on the task of eating rats and not an intruder. The cats are fed proper, attended to if ill, and have become a part of the museum’s heritage.