Telescopes at the Tower being fouled on?

The ravens of the Tower often interrupted the work of John Flamsteed, the first Astronomer Royal of England by fouling his telescopes until he moved to the Greenwich observatory in 1676. The King ordered the ravens killed but he was reminded of the legend that if the ravens left the Tower, the monarchy would fall. Charles wisely allowed some ravens to survive. In July 1676 Flamsteed moved into the Observatory where he lived until 1684. klik2travel clarify just what the Tower has been used for and how many ravens are in residence now http://klik2travel.com/london/k2t.php