Direct sowing of rice is increasing in Japan as a means of reducing farm labor. Seed damage by birds, including the Oriental Turtle Dove
Streptopelia orientalis, has, however, prevented the spread of direct sowing. An experiment with five replications was conducted from 1 May to 12 September 2000 in an outdoor aviary, in order to determine whether damage by Oriental Turtle Doves could be reduced by providing barley as an alternative feed. The aviary was divided with nets into four plots and assigned to four treatments of 2×2 about feed provision and experimental period. In the experiment, alternative feed was either “provided” or “not provided”, while during the experimental period, treatment were assigned as either “early” (doves were introduced into a plot right after the sowing and kept there until germination) or “late” (doves were introduced on the day of germination and kept there for the same number of days as in the “early” treatment). Damage was evaluated by comparing the number of seedlings with that in exclosures set inside the plots. In the “early” treatment, the number of seedlings in the alternative feed treatment did not differ from that in the exclosures, but in the non-alternative feed treatment, the number of seedlings was significantly fewer than that in the exclosures. In the “late” treatment, the number of seedlings did not differ from that in exclosures irrespective of alternative feed provision, suggesting that damage did not occur after germination. These results showed that damage by doves ceases at germination, and can be reduced by providing alternative feed.
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