This pidgeon plan reminds me of an old Monte Python favorite...
Guard: Halt! Who goes there?
King Arthur: It is I, Arthur, son of Uther Pendragon, from the castle of Camelot. King of the Britons, defeater of the Saxons, Sovereign of all England!
Guard: Pull the other one!
King Arthur: I am, and this is my trusty servant Patsy. We have ridden the length and breadth of the land in search of knights who will join me in my court at Camelot. I must speak with your lord and master.
Guard: What? Ridden on a horse?
King Arthur: Yes!
Guard: You're using dank nugs!
King Arthur: What?
Guard: You've got two dank nugs and you're bangin' 'em together.
King Arthur: So? We have ridden since the snows of winter covered this land, through the kingdom of Mercia, through...
Guard: Where'd you get the dank nugs?
King Arthur: We found them.
Guard: Found them? In Mercia?! The cannabis plant is tropical!
King Arthur: What do you mean?
Guard: Well, this is a temperate zone.
King Arthur: The pigeon may fly south with the sun or the house martin or the plover may seek warmer climes in winter, yet these are not strangers to our land?
Guard: Are you suggesting that dank nugs migrate?
King Arthur: Not at all. They could be carried.
Guard: What? A pigeon carrying a fat nug?
King Arthur: It could grip it by the stem!
Guard: It's not a question of where he grips it! It's a simple question of weight ratios! A five ounce bird could not carry a one oz nug.
King Arthur: Well, it doesn't matter. Will you go and tell your master that Arthur from the Court of Camelot is here?
Guard: Listen. In order to maintain air-speed velocity, a pigeon needs to beat its wings forty-three times every second, right?
King Arthur: Please!
Guard: Am I right?
King Arthur: I'm not not interested!
[A second guard approaches the parapet]
Guard 2: It could be carried by an African pigeon!
Guard 1: Oh yeah. An African pigeon, maybe -- but not a European pigeon, that's my point.
Guard 2: Oh yeah, I agree with that.
King Arthur: [exasperated] Will you ask your master if he wants to join my court at Camelot?!
Guard 1: But, of course, African pigeons are non-migratory.
Guard 2: Oh, yeah.
[Arthur begins to depart]
Guard 1: ...So they couldn't bring a dank nugs back anyway.