1. This paper describes breeding biology of the Eastern Great Reed Warbler. Field work was carried out from 1962 to 1964 at Gamou coast near Sendai in the north-east Honshû, Japan. Study area consisted mainly of reed marsh with grassy and wooded area. The birds settled in reed marsh and use grassy and wooded area for feeding ground. 2. The first date of spring arrival of male in different localities were discussed. At Gamou, spring arrival ranged from mid-April to early June, but most of the males arrived by mid-May. Males arrived at the study area in waves which coincided with warm waves in air temperature. 3. Process of establishment of territory was described. Average size of territory decreased inversely with the increase of number of males and changed from about 2500m2. in early May to about 900m2 in early June when all males settled. As the species breeds at high density in the restricted reed marsh, it seems better to consider that the Great Reed Warbler breeds in grouped territories. 4. The Great Reed Warbler is partial bigamy. At Gamou, 71.6 per cent of males were monogamous, 15.8 per cent bigamous and 12.6 per cent were unmated males. The earlier arrivals of males, the higher the pairing success. The average size of territory in unmated males was larger than that in mated males. It suggests that quality of territory may be important for pairing success. 5. Egg-laying extended between mid-May and mid-July, with a peak in early June. Clutch-size ranged from two to six eggs and the commonest was five eggs. The number of young raised per nest was higher in clutch of 5 than the others. There were seasonal changes in average clutch and in number of yound raised per nest. These seasonal changes coincided with that in egg-laying. 6. There were two kinds of reed marshes at the study area; Phragmites marsh and Rottboelia marsh. Pairing success of males and breeding success of pairs in the former were different from those in the latter. In the former, most of the males mated and some were bigamous. On the other hand, about a half of the males in the latter were unmated and the rest were monogamous. Similarly, the number of young raised per nest was considerably higher in the former than in the latter. Therefore, it is concluded that the Phragmites marsh is more favourable habitat than the Rottboelia marsh.
1. This paper describes territory and its function on the limiting of breeding density of the Great Reed Warbler in the favourable habitat. Field work was carried out at Gamou coast near Sendai in the north-east Honshû, Japan. 2. The reed marsh was divided into two kinds in terms of species of reed; Phragmites communis marsh and Rottboelia latifolia marsh. In the Phragmites marsh, breeding success, including pairing success of males, and breeding density were higher than in the Rottboelia marsh. Hence the former was found to be favourable habitat. 3. Reed marshes were not occupied by a number of males all at once, but were filled up gradually from late April to early June. There were three phases in the process of settlement of males; early migrants settled exclusively in the Phragmites marsh (first phase) and then new-comers settled in either marsh (second phase). Finally, the Rottboelia marsh was occupied by later arrivals only after the density in the Phragmites marsh had reached to the highest level (third phase). 4. In the Phragmites marsh, the average size of territory decreased inversely with the increase of the density until the end of the second phase and did not decreased any more in the third phase. 5. Intruders were found until the middle of June. The number of intruders reached a peak in the late half of the second phase and there were still several intruders in the Phragmites marsh during the third phase, although they could not settle there. 6. The males defended its territory against intruders by means of chasings. The frequency of chasings was proportional to the number of the intruders. However, the chasing behaviour in the Phragmites marsh was more vigorous in the third phase than in the other phases. 7. Therefore, it was suggested that the average size of territory in the Phragmites marsh decreased to a limit to which territory can be compressed, thus later arrivals were forced to settle in the Rottboelia marsh by the territorial behaviour of males that already settled in the Phragmites marsh. 8. It is concluded that territorial behaviour limits the breeding density of the Great Reed Warbler in the favourable habitat.
This third part reports the observations of family life from 31 to 34 days after hatching, 5-2 days before flying of chicks, May 19-22, 1969, of a territorial breeding pair of Jungle Crow Corvus macrorhynchos. It was confirmed that one adjacent pair had the nest in gingko tree (in American Embassy) 300m apart from the nest under observation. 1. In this later part of nestling period, the female could have occasional long free recessions of more than 30 minutes off the nest for her own exercise (by chance also food taking), flying to peripheral buildings within the territory far from the nest, whence she advertised herself with 'ka, ka' notes to her mate who stayed on duty while her absence watching around the nest tree on high top of building or a tree, and he called her back if she was late to return. Although the male's long absense from nest site is for food search for the family, the female's long recessions are principally for her own excercise, her chief source of food being those brought and stored by the male at various places around the nest site. The time spent by male and female together increased and became more frequent to be ready for family life with fledged young. 2. During the early morning parents are active eating for themselves and feeding the chicks with stored food around the nest, each of them visiting the nest with more or less 30 minutes intervals, average 15 minutes by both sexes, but the male soon begins his food search for the day widely within his territory and his feeding intervals (to chicks) are prolonged, and those of the female are shortened. Thus, on May 19, 12.35-16.13 p. m., the female's intervals were average 19.30min., as against the male's of 78min. (also on May 20, 10.00-11.30 a. m., the average feeding intervals were 38min, in the female and 72min. in the male). Therefore, the total average of feeding intervals is kept rather constant. 3. Since May 19, 5 days before chicks' flying from the nest the female no more stayed in nest for night brooding. On May 21, she showed still some hesitation in flying off to roost, since after she had once flown to a building in the direction of the roost, returned to a tree near the nest where the male was perched. Then, with usual weak 'ka' note of roosting take-off, she flew off to roost followed by the male. On the next day, May 22, the pair, after resting a while billing each other and preening on the gingko tree near the nest, took off together directly to the roost, 29min. before the sunset at 1900 Lux. 4. Having slept in common flock-roost, the male and female returned together at 4.02 a. m. to their territory 30min. before the sunrise (4.31 a. m.) in the dark of twilight of 0 Lux, flying low through the buildings, 20m. apart each other, and thrusted themselves like an arrow into the dark foliage under the nest tree. Then, they silently waited a while until 4.15 a. m., 15 Lux, when the male first uttered 'ka ka ka ka, ' to which the female replied and each bird began its own morning schedule, keeping communication with 'ka ka' notes until it got light. 5. In this period of later nestling stage, the female was as nervous as to suddenly fly off for defense with food in her bill, if she perceived a trespassing other crow while she was feeding, and the male took much more conservative attitude, sometimes not showing apparent response to the trespasser. 6. The female's (rarely-once-also male) soft nasal 'nga' note toward nestlings became frequent as the chicks grow near to leave the nest. 7. The timing of the female's above attitude toward grown chicks near their flying from the nest and her change of roost from night-brooding to roosting take off from nest site, may be a series of correlated behaviors.
In Japanese Islands, P. montanus restrictus distributes as resident in Hokkaido, Honshu, Shikoku and Kyushu, which are four large islands in Japanese Islands. On the other hand, P. palustris hensoni inhabits as resident in only Hokkaido and its adjacent small island, Rishiri, and therefore the two species are sympatric in Hokkaido. In this paper the morphological differences between the two species in the hand are mentioned on the purpose of clarifying identification criterion for Japanese banders. During autumn banding in Hokkaido, 1975, the differences of (1) the size and shape of beak, (2) the colour of head cap, (3) the colour of outer web of large wing feathers, mainly secondaries, and (4) graduation of tail were compared and measured for 50 birds of P. palustris hensoni and 32 birds of P. montanus restrictus. Wing length and body weight of the two species are shown in Table 1 and Figure 1. From these, body size of P. palustris hensoni is a little larger than P. montanus restrictus as a whole. Beak length (exposed culmen), beak height, and beak width of the two species are shown in Table 2, Figure 2, and Photograph 1. From these, apparently beak size and shape of P. palustris hensoni is stout and short, as compared with, beak of P. montanus restrictus is fine and long. Further indeces of the characteristics of beak shape were considered (Figure 5 and 6). One index, I1 is the product of beak height and beak width (Fig. 5), and another index, I2 is the ratio of I1 and beak length (Fig. 6). They separate clearly the differences of the thickness of beak base of the two species. The differences of colour of outer web of secondaries and also head cap are good indicators to identify the two species. The measurements of graduation of tail are shown in Table 4. The birds which graduations of tail are 2-4mm are 96% of P. palustris hensoni out of 48 birds, while in P. montanus restrictus the birds which graduations of tail are 5-8mm are 93% out of 28 birds (Table 4 and Photograph 2). By checking the four morphological differences above mentioned, all birds of the two species were easily identified. Incidentally, on Honshu, Shikoku, and Kyushu P. palustris hensoni is absent. It is evident that the habitat of P. montanus restrictus is conifer forests through all seasons. We think from our observations that at the least on northern and eastern parts of Hokkaido, P. montanus restrictus occupies, of course, again conifer forests and also the breeding habitat of P. palustris hensoni is rather conifer forest than broad-leaved forest, and that they are ecologically isolated in the way which they live in the same habitat but separate feeding.
1. In the Autumn of 1974, Rustic Buntings Emberiza rustica and Reed Buntings Emberiza schoeniclus were captured and measured at Lake Fukushima, Niigata Prefecture. The measurements taken were divided into juvenile males, adult males, juvenile females and adult females, and analysed. 2. In Rustic Buntings, significant differences were found between the mean weights of the adult male and of the adult female, and of the adult male and juvenile male, between the mean wing lengths of the adult male and adult female, of the juvenile male and juvenile female, of the adult male and juvenile male, and of the adult female and juvenile female, between the mean tail lengths of the adult male and adult female, and also between the mean culmen lengths of the adult female and juvenile female. 3. In Reed Buntings, significant differences were found between the mean weights of the male and female, between the mean wing lengths of the male and female, and of the abult male and juvenile male, between the mean tail lengths of the male and female, and of the adult male and juvenile male, between the mean tarsus lengths of the adult male and juvenile male, and also between the mean culmen lengths of the juvenile male and juvenile female. 4. Generally, the mean measurements of the adult were bigger than the juvenile in any sex, and the mean values of the male were bigger than the female in any age. The causes of these differences are discussed in the text.
In December 1974, wings and legs of Japanese White Stork Ciconia ciconia boyciana shot by hunter, was found in Tatsuno-cho, Matsuzaka City, Mie Prefecture, and a skull of the same bird was obtained in January 1975. It had apparently been observed since early November. This is the first record of Japanese White Stork from Mie Prefecture.
The number of domestic pigeons Columba livia var. captured by reason of exterminating noxious wildlife was investigated by using the Statistical Data of Wildlife between 1947 and 1974, published by the Forestry Agency and Environment Agency. Capturing of the domestic pigeons started from 1962 and until 1967, the number of the captured bird was few, and the area where the extermination was enforced was quite limited. However, after 1968, the number of captured birds increased immensely, and every year, the areas of the enforcement of the extermination widened, and now, the capturing of the domestic pigeon is undertaken throughout the country. Also, the density of the exterminated domestic pigeons (accumulative number of the captured domestic pigeons/areas by Prefectures) was calculated in order to compare the number of the captured domestic pigeons by Prefectures. From this calculation, it was revealed that Aichi (10.23 birds/km2), Tokyo (6.32 birds/km2), Kanagawa (5.78 birds/km2), Saga, Shiga, Osaka, Nagasaki, Mie and Shizuoka Prefecture were all areas of high density where the density of the exterminated domestic pigeons was over 0.10 birds/km2. From this result, it can be presumed that the geographical distribution of these nine prefectures correspond with the industrial areas of our country. The accumulative number of the captured domestic pigeons in these nine prefectures amount to more than of the whole number of the captured birds.