Pigeons are homing birds and prefer to be in their roost. They always know their way back to it.
That’s how messenger pigeons, or homing pigeons, work. They are bred and trained to fly back home to their roost. This is done by repeatedly taking them a bit further and further away each time.
But then after a while they can navigate back to their roost from anywhere from dozens to sometimes hundreds of miles away. Though it is also possible for them to get lost.
So they don’t navigate to a new place, they just go home, we aren’t really sure how they do it, but that’s what they do.
Messenger pigeons work less like a text message and more like a one-way, one-use phone line.
So, messenger pigeons are only useful really for sending messages back home or back to base.
So if you are a soldier back in WW1, you job may have been to carry cages of these pigeons so you could strap messages to them for them to fly back to base with, letting base know what was happening at the front.
For two place to communicate back and forth, they would both need pigeons that are from each other’s “home” to be able to do that.
