The nest production of a swallow building which measures 8 m x 20 m of 4 stories high owned by Halim in Karawang, West Java, had been steady until 2002.
The production was so hard to move swiftly from 200 nests/ harvesting. However, now the nest production of Collocalia fuciphaga has risen double in 3 years.
It happened ever since each void is illumined with a lamp. According to Ir Lazuardi Normansah, the light is needed to guide swallows to every floor in order to look for a comfortable location.
The utilization of light is effective especially on new house of which the light cannot penetrate to the basement. But the light is intended merely to make the room gloomy.
Therefore, it only requires a 5 watt lamp which is placed into a plywood box of 10 cm x 10 cm x 15 cm.
The bottom part of the box is perforated as big as a coin of Rp500. (Lastioro Anmi Tambunan)