R&D Project on Barn Owls
Chumporn Palm Oil Industry Public Company Limited (CPI), the first integrated organization in palm oil business in Thailand, have set-up R&D projects on barn owl in the object of reducing fruit damage from rats by natural controlling, no chemical uses that hurt environment. Besides, it saves the company cost in buying chemicals by millions baht each year. It is believed to be a good practice for communities to aware and preserve their environment and follow so at last.

Life Cycle of Barn Owls
Male and female barn owls are so similar in their appearance that we generally cannot identify which one is male or female. Naturally, barn owls’ life span is approximately 5-7 years. They breed after their one year old and lay their eggs 1-2 times each year. Out of mating season, they will not stay in dens at day, but perching on trees (including oil palms), especially ones that have abundant leaves, to conceal themselves from attacking by other birds. A mating season is around September – February. After finding their mates, they will look for natural dens as their abodes for breeding and incubation. In other words, they cannot build abodes by themselves as well as they do not use material to place support their eggs. The Female barn owls will incubate eggs in abodes while the male will live outside, hunting food to feed their family until their children grow. After that the female will live outside too, and help hunt to feed the young further on. The number of eggs laid each time is around 5, the number of survival is 3-4. The incubation period is around 30 days. The young do not hatch from eggs at the same time as well as the young are not equal in size. The growth thereafter is quite fast, 60-70 days afterwards they will leave their abode to the enormously endless world. As for their parent, if the environment is fertile enough, they will start produce the second round eggs later on.
The Capalibity of rat hunting
In oil palm surrounding, whole food of barn owl is rat only, especially white-stomached rat (sometimes called Malaysian wild rats). One barn owl can hunt two rats each day or 700 rats per year. Imagine how many rats will be eliminated each year, if there are 10 barn owls in plants – 7,000 rats will be eliminated, think further about how damages on our productive plants is, if we do nothing with this oil palm foe. The natural control will overcome this without using any chemicals and that it save cost for chemicals and labors (who scatter chemicals) thereby. More importantly, the environment will not be hurt by this kind of rat elimination.

How to have barn owls eliminate rats?
Farmers can introduce barn owls to live in oil palm plantations by building owl abodes in their areas. The abodes, of which designs are various, can be made of by different kinds or materials (e.g. wood board, plywood, plank etc.). The abode should be 60 cm. x 80 cm. x 60 cm. (width x length x height) with top roof. Water barrels could also be applied to be owl houses by paving plywood or tiles inside. The house should be supported by iron or concrete post and located 2.5 meters above ground. The owl abodes ought to be built in a placid area and the proportion of 1-2 abodes per 50 rais is recommended in building. By doing so and leaving it naturally, barn owls remaining in nature may enter to live in such created houses, but it may be time consuming, perhaps several years later. The most effective and fastest way is to bring barn owl young from breeding. Since they are nurtured and trained by specialists, they will quickly get accustomed to hunting, living in created abodes and mating. Once the barn owls are introduced to plantation, they will spread over their young so that the rat population is controlled finally.

How many barn owls are appropriate to plantations?
Since barn owls do not compete with each other in hunting, farmers are able to build many barn owl houses in their area. Anyway, the owl houses are suggested to keep 50 meters away from each other. The answer to the question how many barn owls are just to given area may not be exact. Anyhow, by considering that a couple of barn owls with their two generations of young (approximately 3 young owls per 1 generation) will normally hunt in a range of 50 rais during their mating season, we may utilize this fact to estimate the proportion of “a couple of owls per 50 rais”   
(1 acre = 2.53 rai) after all.

Benefits of nature control by barn owls?
Not only farmers are safe from hazardous substance and save cost / times in operation, but they also boost price of fruit sold to factories, because damage on fruit, which is a factor concerned in determining price, was significantly reduced when barn owl population increases in balance with mouse population.

Limitation
In the initial phase which the number of barn owls is not considerable, farmers may use other methods in conjunction with barn owl to control rat populations. Anyway, chemicals should not be used, because it may harm barn owls.

Suggestion
Farmers with small land should co-operate with their neighbors to help each other preserve barn owls home in the area.