What if we encrypt the pigeon?

You also have to be able to find the carrier pigeon in use (as well as being aware that carrier pigeons are in use) - and in a city like NYC where there are probably millions of pigeons, that’s an inconceivably difficult task.

And what are your feelings on the telegram?

... carrier pigeons are super easy to track (they’re physical and fly between points), they carry relatively easily decryptable messages, and they’re super vulnerable to man-in-the-middle attacks (catch pigeon, read message, replace message with disinformation, release pigeon on its way).