Because of its size, it is very hard to control the light density. Therefore the owner painted the roving wall with black paint to reduce the glaring.
The temperature inside is killing the birds. I don't have to ask him what the Temperature is. A single layered sand brick without plaster...you know what I mean.
In Hot season this Swiftlet farm is like an oven easily reaching 34C perhaps more. Without wall insulation when temperature falls at night the internal temperature would fall below 25C.
Naturally, Swiftlets could sense this. They knew if they build nests in such Swiftlet farm their eggs can never hatch and the embryos will die. So it is better to find a more conducive environment, in other word a better Swiftlet farm...perhaps neighbor' Swiftlet farm.
So there you go, it is all boil down to how well you could interpret and understand Birds behavior. Once you had acquired this knowledge then you could build a Swiftlet farm that like by Swiftlets.
Now I have to come out with a plan to safe this Swiftlet farm. It is not easy but it can be done.
Good Swiftlet Farming All!
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