The earlier post on the feeder for the Spotted Doves (Streptopelia chinensis) and Eurasian Tree Sparrows (Passer montanus) show how these birds behave on the platform of the feeder provided in the garden LINK.
With so many birds feeding and a free flow of birdseeds, the bottle gets depleted fast. As long as the bottle has an adequate supply of birdseeds, the contents get easily displaced, especially when the platform is shaken by the presence of the birds. But when the level of birdseeds reaches the level of the holes, the birds peck into the holes to get at the seeds. The problem arises when the level falls below the holes. Then the feeder needs to be shaken vigorously to dislodge the seeds. But who can do this? Not the sparrows, being small and light.
The bigger Spotted Doves showed intelligence in getting at the remnants of the birdseeds inside the bottle.
One evening, I heard repeated clanking coming from the direction of the feeder. On closer inspection, I found a dove jumping from a nearby vine above the feeder onto the platform, then flying back to the branch. This was repeated a few times. The impact of the dove landing on the platform caused the latter to tilt sideways, resulting in the iron rod that is slotted through it and into the base of the bottle, to strike the side of the wider metal tube of the stand that the feeder is slotted into. This in turn caused the remaining birdseeds inside the bottle to be thrown out through the basal holes.
So now, whenever I hear the clanking of the feeder, I know that it is time to replenish the bottle with birdseeds.