Following the first part (on data of April 13-30), this second part describes the observation data of May 4-18, 1969 on the parental behavior of a breeding pair of Corvus macrorhynchos in middle nesting period (16-30 days after hatching). 1) The daily life of the pair was the same in general pattern as in earlier nestling period (cf. first part), but the amount of each feed for chicks carried in parents' buccal sac seemed to have increased judging foom larger swollen throat of parents. 2) With the growth of chicks, the female occasionally spent rather long time (more than 30 minutes) off the nest for her own feeding or excercise flying to some distant buildings, during which the male rests and watches at high top of a building. After along off, the female fed the chicks a few times with short intervals. 3) The female's defence drive increased with the growth of chicks. She became aggressive even against small birds such as the bulbul Hypsipetes amaurotis which may fly into her nesting gingko tree and she was observed to straightly fly back from distant building to that gingko tree which a bulbul flew in. She also at once chased away a Psittacula parakeet (an escaped cage bird) which happened to fly into that gingko tree. 4) As mentioned in the first part, the female was usually the more aggressive than the male against trespassing other crows, but when she was out for own feeding, etc., the male was seen to chase the intruder. 5) Parent birds are very nervous in this period (May 13, 14, 25 and 26 days after hatching) for protection of chicks. They continuously uttered warning 'ga, ga' note at lower branches of the nesting tree against a cat on the ground. Against approaching observer, the female came down to overhead branch, with the same 'ga' note, vigorously pecking at perch, breaking down twigs and snatching leaves which she may grasp with one foot (see photo 2 and photos in Misc. Rep. Yam. Inst. no. 41). These are displacement threat actions released against strong enemy. The male, however, only watched her from up on high branch, with continuous 'ga' notes. 6) As the chicks grow from 16 (May 4) to 30 (May 18) days after hatching, the female's off-nest time increased from 0.5-32 (av. 11.4) minutes to 6-41 (av. 19.6) minutes with the decrease in on-nest time from 1-15 (av. 8.0) minutes to 1-5 (av. 1.8) minutes; thus with the decrease of brooding rate from 41.31% to 8.80%. 7) The feeding frequency and interval varied by date and time of day and were more variable in the male, but rather constant at more or less about 14 minutes intervals or 4 times per hour when feedings by male and female are totalized (These will be analysed in later report). 8) From 17 days after hatching the parents took, after feeding, chick's feces which they stored in the buccal sac to drop from the branch of nearby tree, but this was not frequent during the observation period. In one occasion, the female didn't drop the feces and probably ate it. 9) Toward middle nestling period, female didn't remain long in the nest after feeding the chicks and thus the male and female often returned to nest in turn for feeding of chicks. If the male came back, with food in throat, and the female was still in the nest, he waited until she gets out of the nest (not passing food to her as in incubation (or brooding) period) (But, rarely he came to nest and female flew out). The female, on the other hand, would come into the nest although the male was there, and the male at once flew out of the nest (But, once the female was observed to wait until the male came out of the nest). Thus, the male and female do not feed the chicks together and the female is behaviorally slightly dominant in feeding. The female usually stayed a few minutes in the nest after feeding, but the male's feeding ended in a minute.
Observations on birds were made on Yururi and Moyururi Islands, known as natural monument of sea bird colonies, off the coast of eastern Hokkaido during the summers of 1960, 1972 and 1973. Incidental observations were also made in the adjacent waters of the islets. Yururi Island occupying an area of 168 hectares has 7.5km of coast line. Moyururi Island is smaller than the former, occupying an area of 31 hectares with the coast line 3km. Both islets are surrounded by rocky cliffs reaching a height of 20 to 30m except for a few coves such as Kato-hama and Aburakoma, where there are beachs. There are a few isolated rocks, Futatsu-jima, Nanatsu-iwa and so on, along the coasts. Both islets are generally flat at altitude of 30 to 40m above sea level (Fig. 2). Five major habitat types can be recognized (Fig. 3). On the flat top of islets there are the grassland dominated by Sasa niponica and the peat bog for Yururi Island and the grassland dominated by Sasa niponica and Calamagrostis langsdorffi for Moyururi Island. Mean temperatures at Nemuro showed 7.1°C in May, 10.0°C in June, 14.3°C in July and 17.1°C in August. During the study a total of 29 species of birds were recorded (Table 1). In addition, other 13 species of birds have been recorded from the study area in summer: Gavia arctica, Fulmarus glacialis, Puffinus tenuirostris, Phalacrocorax pelagicus, Haliaeetus albicilla, Falco peregrinus, Rallus aquatieus, Tringa brevipes, Numenius madagascariensis, Larus hyperboreus, Uria lomvia, Aethia psittacula and Fratercula corniculata. Of them P. pelagicus have been found breeding on the rock stacks, Kamo-jima. Fairly large sea bird colonies were located on the inaccessible rocks, on the flat-tops of steep cliffs and on the steep seaward-facing slopes (Table 2 and Fig. 6). Two to for species of sea birds occurred together on nearly all colonies except for the rocks J and M of Yururi Island, where only P. urile nested (Figs 4 and 5). Supplementing our data by those of Haga (1973) who made a survey on the both islets in late June of 1972, it is estimated that numbers of nests containing eggs or chicks were at least 64 on Yururi Island and 150 on Moyururi Island for P. filamentosus and 170 on the former and 11 on the later for P. urile. On other hand, both species of cormorants were scarcely encountered in the adjacent waters of the islets. The P. filamentosus colonies on Moyururi Island increased from 50 in 1959 to 65 occupied nests in 1960, furthermore to 150 in 1972, enlarging nesting grounds. The situation is very different in the P. urile colonies of the islet. Numbers of occupied nests were 25 in 1959, 35 in 1960 and increased to 60 in 1965, but decreased to 11 in 1972. There were 20 to 30 occupied nests of P. urile on the west side cliffs of Yururi Island in 1957 and 72 on the northeast side between I to P inclusive in 1960. However, changes in whole numbers of occupied nests of P. filameutosus and P. urile on Yururi Island are not clear because of the lack of sufficient information for other years or for other parts of the islet, respectively. The two species of cormorants distinctly differed in nest sites. P. filanentosus nested on flat broad parts on the tops of rocks or cliffs, but P. urile on the narrow ledge of steep cliffs (Figs. 7 and 9). In the case of two species nesting on the same rock, the former nested on the flat-ground just above the cliffs and the later on the lower ledges (Fig. 4). The shift of nest sites by year was characteristic for P. urile. For a detailed analysis of ecological separation in other aspects described by previous workers for cormorants, sufficient information was not obtained.
A bird of Zosterops erythropleura was captured and banded at Ota-yama Banding Station, Fukui Prefecture in 7th November 1974. This is the first record from Japanese Islands. The general characters of the bird coincide with the descriptions by Yamashina (1934), Dementiev et al. (1954) and Mees (1957). The characters of the bird are as follows: Measurements (mm): Wing 61; Tail 43; Exposed Culmen 9.45; Tarsus 16.90. Upper parts generally green peculiar to Zosterops, on head and rump yellowish. Throat yellow-ochre; upper breast fine silver-grey; lower breast and belly pure white; flanks dark brown russet (or chestnut). Leg pale grey; toes flesh. Bill, from tip to two third of upper mandible and tip to half of under mandible black, the rest of mandibles pale brown. Iris chestnut. According to Yamashina and Dementiev et al, the bird is probably an adult male. Moult: The bird is moulting on throat and large wing feathers. Primaries 1st-4th fully grown, 5th score 4, 6th-9th score O; secondaries 1st score 3, 2nd-6th score O; Tertials 2nd score 4. 1st and 3rd score O (the moult score after B. T. O.'s denotation). At Ota-Yama Banding Station, 583 and 536 Z. j. japonica were captured in 1973 and 1974, respectively, during autumn banding seasons, and we believe that the most of them were migrating from the northern breeding arears to the southern warm winter quarters. Yet, we have no observation suggesting that the bird of Z. erythropleura might mix with the flock of Z. japonica.
A specimen of a tree sparrow bearing the warty growths of the possible avian pox in the skin was caught near the Faculty of Science, Niigata University, Niigata City facing the Japan Sea. Histological studies were carried out to diagnose this curious growth, and comparison of the tumors of viral origin was made among the entire vertebrate classes.
1) The mortality of the Shearwaters in 1975, especially the Slenderbilled Shearwaters, were surveyed by the questionnaire method. The questionnaires were recovered from 263 persons (Recovery rate 13%), and more than 80% of them were from the members of Japan Wild Birds Society and Japanese Association for Preservation of Birds. 2) The number of the dead shearwaters, according to the questionnaire of 1975, was approximately 19.768, the number of birds found in emaciated condition was 787, and the number found afloat was 14, 924. The recorded species were Slender-billed Shearwater Puffinus tenuirostris (account for 76, 2% of all dead and emaciated Shearwaters), Streaked Shearwater Calonectris leucomeas (account for 0.8%), Sooty Shearwater Puffinus griseus (account for 0.6%), Pale-footed Shearwater Puffinus carneipes and Wedged-tailed Shearwater Puffinus pacificus. (Among these, the species account for 22.4% of all the dead and emaciated birds were indistinct.) 3) The dead Shearwaters were distributed in the districts along the Pacific Coast, from Kagoshima Prefecture to Hokkaido. The distribution of the dead Slender-billed Shearwaters that have the highest death rate cover 15 Prefectures from Kagoshima Prefecture to Hokkaido. 4) According to the survey, most of the dead Slender-billed Shearwaters were recorded from the beginning of May to the beginning of July, and the time of great mortality seems to lag in the northern districts. Throughout the country, the times of highest shearwater mortality were from the beginning (56.2%) to the middle (26.2%) of June. 5) Many of the people who have answered the questionnaires reported that the stomachs were empty when they dissected the dead shearwaters. However, few of them reported that such things as coal tar, sand, pebbles, piece of wood and styrofoam etc. were found in the stomach. According to the result of the dissection in 5 cases, there were no external wounds, and all were juveniles. 6) It was reported that the shearwaters were found feeding in the corfs in some part of the districts. 7) The mortality of the Slender-billed Shearwaters before 1975 has been recorded mainly in 1973 and 1974, and in 1962, 1964, 1969, 1970 and 1971, mortality was recorded only in one part of the district (City of Sendai). Especially, the record of 1964 accord with the report of Dr. Nagahisa Kuroda on the mortality of the Shearwaters (1967). Also, the record of 1964 showed that the dead Shearwaters were distributed as far north as the Tohoku District. 8) The distribution of the dead Slender-billed Shearwaters in 1974 and 1975 further extended to Tohoku and Hokkaido compared with the record of the distribution of 1966 and 1973, and there seemed to be a tendency that the time of the mortality lag according to the extension of the distribution.