Some Swiftlet farms attract more Bats than Siwftlets.
This type of Gecko is commonly found in Stanalone. If they could eat a mice what is baby birds.
Monitor lizard can climbs walls. If the exterior is not plastered smooth then they could easily climb in thru the entrance hole.
They are expert in climbing and like eating birds. They used to climb trees in search for birds nests looking for the young and adult birds especially coconut trees.
Some spiders are poisonous. Don't simply remove them with your hand even you wear gloves.
Snakes are good climber too.
Once I discovered a pair of Musang living in the ceiling of my Swiftlet farm. You can see the reaction of birds when they home coming. If It is different from usual, there must be something not right.
Smaller then Normal Owl. This Malayan Owl could capture birds in the air.
Centipede they like cool and damp places like Swiftlet farm which provide plenty of insect which they could eat.
Different type of centipede. It can be found in farm.
Rats could also be found in farm. 
Never leave paper products in Swiftlet farm. Cardboard , news papers and so on. Many farmers use Newspaper to seal off the Vent-hole. It is really unwise.
I have seen few failed farms in Kedah which have Pigeon nests at the roving area.
After visited your Swiftlet farm if you discovered your legs and hands have red spots and it is itchy. That is the job of fleas.
Can be easily seen on the walls.
Planks infested with termite. No wonder no nests.
Termites.Good Swiftlet farming All!
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