Responses of 5 eastern turtle doves Streptopelia orientalis to bitter taste quinine and saccharose octaacetate (SOA) were investigated with two-dish preference tests.
1. Marked individual differences were found in preference experiments for the foraging site in which control corns coated with dour of wheat were set to two dishes. Two doves showed no preference for the site and other two rejected one site (statistically significant in 2 out of 3 and in 7 out of 10 experiments, respectively). Another dove rejected one site in an experiment and preferred the site in another one out of 7 experiments.
2. Preference experiments for quinine and flour by olfactory cue alone showed no difference and following results were considered to be caused by taste preference.
3. Treated corns coated with bitter taste and control corns were set to each dish at random in every 3-hr period of trial. Preference experiments were designed as ascendant (from smal to large dose of bitter substance) and the following descendant (from large to small dose) series. Doves that rejected treated corns at certain dose on ascendant series rejected at smaller dose on descendant series. The dose that doves showed aversive response varied individually. Four doves rejected both quinine and SOA but one dove that rejected quinine did not respond to SOA.
4. Doves tended to reject quinine-treated corns at smaller dose than SOA-treated ones both on ascendant and descendant series.
5. Doves do not prefer beans to corns among commercial mixture of grain for doves. And two of 3 doves preferred quinine-treated corns to beans coated with flour.
6. From the results above it is clear that eastern turtle dove do not prefer bitter taste quinine and SOA but they do not always reject the bitter taste.

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Monte Carlo simulation was conducted to evaluate the effects of the differences of site preference to two-dish choice experiments.Three parameters, the frequency of visit to one foraging site A (FV), the amount of food taken from dish A (FTA) and the coefficient of aversion to treated-food(CR), were used in this model.
1) In control experiment, in which the same amount of food was placed in both dish A and B, changes of FV (from 0.05 to 0.5)and FTA (0.04-0.1)affected the site preference.The percentage of experiments in which the site B was preferred increased significantly as the values of FV and FTA got smaller.
2) In two-dishch oice experiments, the effect of treatment was affected by the values of CR. Greater the value of CR, greater the percentage of detection of the effect of treatment.When CR increased linearly whenever a birdvisited the foraging site, thepercentage of detection was higherthanwhenCRwasalwaysconstant.
3) It is suggested that these three parameters could be estimated by observing behavior of birds and the changes of weight of food supplied.
4) This model suggested that the difference of site preference, if it did not always occur in all control experiments, would have a littl eeffects on the results of two-dish choice experiment.

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Diet of adult House Sparrows Passer domestics was studied by gravimetric analysis of gut contents during August 1988 to July 1989 at Ludhiana, India. Cereals dominated the food forming 83.6% of total diet. Weed seeds and animal matter constituted only 6.2 and 4.3%, respectively. Shannon-Wiener index and Levins' index of food-niche breadth were calculated to be 0.75 and 3.90, respectively. Relative percentage by weight of different food types was significantly positively correlated with their occurrence in the guts (r=0.67, n=16, P<0.005). Pearl millet was the most abundant food type during August through November, whereas wheat dominanted the diet during January through April and July. Rice and maize were recorded in the guts in three months each. Weed seeds were eaten by sparrows throughout the year except in September, January and February. Egg-shell pieces were recorded throughout the year (except June) but insects were found only in three months (June, August and December). Grit was recorded in all months constituting 4 to 43% of total gut contents (annual average 21%). The diet of sparrows was comparatively more diverse during March-June, August and November than during rest of the year as revealed by fluctuations in two indices of food-niche breadth.

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Observations of birds on Oshima Ooshima Island, 55 km west of Era, southern Hokkaido, was done during the period from 8 to 10 October 1990. A total of 1, 235 birds consisting of 36 species were observed. The most abundant bird was the Siskin Carduelis spinus (n=435, 35.2%). Other main species in order of decreasing were: Great Tits Parus major (n=130, 14.7%), Oriental Greenfinches Carduelis sinica (n=106, 8.6%), Rustic Buntings Emberiza rustica (n=34, 2.7%), Jungle Crows Corvus macrorhynchos (n=35, 2.8%), Temminck's Cormoramts Phalacrocorax capillatus (n=29, 2.3%), Bullfinches Pyrrhula pyrrhula (n=20, 1.6%), and Peregrine Falcons Falco peregrinus (n=18, 1.5%). As the rare bird species on this island, 16 Mandarin Ducks Aix galericulata, one Tengmalm's Owl Aegolius funereus, and one Pine Bunting Emberiza leucocephala were observed.

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We observed that Japanese White-eyes Zosterops japonica sucked honey dews secreted by two species of small jumping plant-lices, Heterophylla cubana and Stenopsylla nigricornis. This is the first observation of inter-specific relationship between homopteran insects and white-eyes. Such a foraging manner might be common in White-eyes. Although honey dew of homopteran insects is not neccessary to White-eyes as nectar resource, the homopteran insects seems important as insect foods.

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I observed that a Japanese White-eye Zosterops japonica sucked necter from extrafloral nectaries of the Terminalia catappa L. in the Bonin Islands. The extra-floral nectary secretes sugar water to establish the antiherbivore mutalism. In this case, the White-eye seems play as a opportunistic defender.

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I observed that two Carrion Crows Corvus corone ate the buds of a cinnamon tree Cinnamomum camphora in Japan. This seems the first observation of cinnamon bud feeding by the Carrion Crow.

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