I just found some interesting information about this species. It is regarding the usage of barn in paddy field in malaysia. The finding is great:

BARN OWLS AS A BIOLOGICAL CONTROL AGENT OF RATS IN PADDY FIELDS

Hafidzi, M.N., Zulkifli A., Kamarudin A.A.
Symposium on Biological Control Agent of Rats in Paddy Fields
MARDI Training Centre, Serdang, Selangor, Malaysia
18 – 19 March 1999

Summary: The role of barn owls, Tyto alba, in controlling ricefield rats in paddy fields was investigated based on the census of barn owl population, damage census on rice crop and baiting requirements in Selangor, where the barn owl project has been implemented from 1988 to 1997. Rice crop loss due to rat activities before the implementation of the project ranged from 5 to 10 %, but this was reduced to less than 1 % after that. Monthly occupancy rates and proportion of boxes with eggs and owlets showed that the barn owl population is influenced by the paddy planting stages. It reaches its peak during the period between harvesting and the booting stage of the subsequent crop which also coincides with the rat reproductive cycle.

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