Habitat selectivity of ricefield rats during March (tillering stage of rice crop; nonbreeding season)and June (ripening stage of rice crop; breeding season) for day and night fixes for each habitat, Vinh Phuc province, Vietnam. The selectivity index is calculated by dividing the proportion of observations of rats in each habitat type by the proportion of habitat available. A selectivity value of > 1 implies preference while a value of < 1 implies avoidance.