Birds do make territorial marking in Farms. They do this to find out whether the farm is safe for them to stay also to indicate to others as well. If you are observant enough you would see Birds dropping at the walls of the roving area. They are splashed on the walls this is done by purpose the more birds stayed in the farm the more dropping splashed on the wall. It is their adaptation process, so the next time they fly in they would know that this is their farms and it is safe to come in.
Often for new farm when the sound is switched on birds would fly in and out for many times this is an adaptation process. If they sensed the farm with too strong of unwanted smells (Cement smell, worker body order, Plank smell, wire and tweeter plastic, etc) they would reject it. Often birds fly 1-2 ft from the wall and 1-2 ft below the nesting planks. You see how close they are to it and if these walls and planks have odors they would sense it easily. That is the biggest problem with new swiftlet farm.
Therefore we have to make the new farms smell like old farms at the same time creating an environment that filed with scent of aroma ( hormone) that trigger the mood of the Birds into mating.
