@ZySoua there's a science fiction story (Heinlein?) about trading with aliens like this. The humans have no way to communicate with the aliens, but prior visitors have worked out a trade system where both parties line up piles of goods in the trade area and take the other's pile when they're satisfied by the deal.
In this story, the captain finds a pornmag on the ship and dumps it in the trade area. The aliens love it and pile their most valuable goods against it. The humans break the bind on the magazine and split it into two. The aliens duplicate their pile in response. Ultimately the humans sell each page individually.
Birds are cool too but tragically unappreciative of porn mags.