Evidence that birds can read

Crow experts over in Japan have figured out a way to stop crows from ripping old insulation material off of pipes (the birds use the insulation for their nests). The researchers simply hung signs that read (in Japanese), "Crows do not enter." The crows seem to be obeying the signs. At least, they abruptly stopped attacking the pipes. This has now been working for three years.

Professor Katsufumi Sato thinks the signs work because people see the signs then look up into the sky for the birds, and when the crows realize they're being observed they fly away. More info: asahi.com

Or maybe the birds can read. I happen to have had in my files an example from 1960 of seagulls in San Diego who obeyed signs ordering them to stop dropping clams on the pavement.

The Lock Haven Express - Apr 7, 1960