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As in many other countries throughout the world, rice is a staple food item in Malaysia. Through the development of improved varieties, irrigation systems, and agronomic practices, rice production there has increased substantially in recent years and the country is now 80-85% self-sufficient in rice. The main limitation to obtaining full self-sufficiency is the lack of additional land area suitable for raising two rice crops annually (Samy 1977). Another factor limiting production is rice crop pests, particularly rats and insects. Birds also are generally acknowledged as pests in rice fieids of this region (FAO 1973, De Grazio 1978), but in Malaysia little effort has been directed toward understanding the nature or extent of the problem. From April 1975 through March 1977, I conducted an investigation of bird damage to rice at a site in northwestern peninsular Malaysia. In this paper, I report the results of experimental caged-and field-feeding trials and present rough estimates of the level of damage caused by birds in rice fields of the area. Various aspects of this work have been presented elsewhere (Avery 1978, 1980). In Malaysia, there are several bird species that potentially are pests to rice. These include the European tree sparrow, Passer montanus; baya weaver, Ploceus philippinus; pin-tailed parrotfinch, Erythrura prasina; Java sparrow, Padda oryzivora; sharp-tailed munia, Lonchura striata; white-bellied munia, L. leucogastra; spotted munia, L. punc- tulata; chestnut munia, L. malacca; and white-headed munia, L. mala. On my study area only the sharp-tailed and spotted munias, and baya weaver were numerous enough to consider. The experiments described in this paper concern primarily the sharp-tailed munia, although some comparisons with the spotted munia are made. These two species are easily maintained in captivity and are ideal subjects for this type of work. Both are small (10-12 g), sexually monomorphic, and abundant in lowland rice-growing areas where they nest in palms, ornamental shrubs, and fruit trees, usually in close association with humans. Although they have been studied previously in captivity, little attention has been paid to their natural history, and information on their relation to the rice crop is largely anecdotal.