[in Japanese]

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A cladistic analysis of Jerdon's Courser (Rhinoptilus bitorquatus) and eight allied taxa supports the validity of the Afro-Asian genus Rhinoptilus and indicates that the sister-species of the Indian relict bitorquatus is the Three-banded Courser (Rhinoptilus cinctus) of eastern Africa.
The present distribution of these two sister forms is evidence for a former biotic link between peninsular India and the savanna habitats of eastern Africa. This distributional trend is corroborated by an additional list of forty-three species or sister-species pairs that exhibit this Afro-Indian pattern. We believe that these data support the notion that there once existed an Afro-Indian fauna that inhabited what was probably a continuous belt of savanna from southern Africa to southern India.
The recovery plan for the critically-endangered Jerdon's Courser should include attempts to develop a captive population of R. cinctus, which could then be used to rear eggs taken from wild populations of bitorquatus. Captive breeding, in concert with local education and efforts to expand protected areas of prime habitat, offers the most promising integrated strategy for the species' recovery.

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[in Japanese]

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This is a review of the urban birds of eastern Asia and of the United States comparing their modifications for city life which have made them successful in that environment. It compares the habitat use by 848 species in Malaysia, Thailand, Japan and United States as seen among 30 locations where more than a million birds were tallied from 1941 through 1988. Using a criterion that an urban bird species was one in which at least one-third of the population was found in city environs, 70 species fell into this category. Compared by 113 characteristics of bird bionomics these species had similarities which suggested that having or developing those characteristics enhanced their success as urban birds. These are listed.

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Chick growth of the short-tailed shearwater Puffinus tenuirostris, in a colony in Southern Tasmania was studied from mid January until the end of April 1988. Hatching took place between 10 and 25 January, with the peak occuring on 18 and 19 January. Fledging success was 35%. Mortality was concentrated in the middle of the nestling period and its main cause was predation by poachers and feral cats. Emergence from burrows began, on average, on the 88.7th night (±2.8SD) after hatching, which corresponded to 13.9 April (±2.5SD). After consecutive emergence for 8.8 days (±3.5SD), they fledged on the 97.1th day (±3.3SD) after hatching, with the peak occurring between April 23 and 29. Hatched chicks, on average, had: 10% the body weight, 40% the tarsus length and 50% the bill (exposed culmen) length of adults and attained adult sizes during the middle of the nestling period. Chicks attained the body weight of about 15% heavier than the average adult, however, they lost 25% of the peak body weight over the last three weeks and fledged at the mean body weight 13% lighter than the average adult. As compared with the early growth of their bony organs and body weight, their feather development was delayed. Tails began to sprout at 45.5 days (±2.6SD) after hatching and outer primaries sprouted at 34.2 days (±2.5SD) after hatching. These parts quickly developed in the second half of the nestling period. However, in 1988 the wings and tails of the chicks did not attain adult size and continued developing at the time of fledging. The long nestling period (97 days on average) and the rotation of growth and development of bony and feather parts might be effective for ensuring survival during the nestling period, by reducing the maximum energy demand for growth.

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1. Although the line-transect census method is very simple and convenient for estimating bird densities, it has certain deficiencies; for example in over represents edge species, suffers from disturbance from the noise of walking and is inapplicability for small patches of forest. For such cases, it is desirable to use the plot census (point count) method. But up to the present, an estimation manner of a true density by this method has not been developed. The true density of birds can not be estimated by the Variable circular-plot method or Fixed circular-plot method, because these methods don't consider the potential effect of the conspicuousness of particular species. Some new methods for estimating the true density of bird communities or respective species by the plot census method compared with the line-transect census method were examined.
2. The recorded number of individual birds by the plot census method changed with the time of day, but the number did not show larger differences between 4:00 to 10:00 in any minutes spent on the plot.
3. The recorded number of individual birds showed a definite pattern of increase according with the time (minutes) extension staying on the plot. But the number does not increase so much comparing with the time increase on the plot.
4. The recorded number of individual birds showed no significant difference between trained observers.
5. The recorded number (P) of individual birds by the plot census method had a good correlation with the number recorded by the line-transect census in the same wood. Also, there is a correlation between the recorded number of individuals (n) of total bird species by the line-transect census (observing radius 50m, walking speed 1.5km per hour, one hour recording covering 15ha from 2 hours after sunrise, under good weather conditions) and the absolute density (D) of total bird species of that area. Then, D can be estimated from P. For example D=17.89 P₁₀+4.29. Where P₁₀ means ten minutes sample of the plot census with 50m observing radius.
6. The possibility of estimating the specific density (D_i) of i species by the plot census was suggested. For example, D_i=(7.31P_10i+6.29)•200/E_i. Where P_10i means the ten minutes sample in the plot census for i species. E_i means the census effectivity, the ratio (%) of the number of i species recorded in the standard line-transect census to the number of territories in that area. But, it was considered that a better way to estimate the specific density of i species by the plot census would be, from the first, to know the plot census effectivity for respective species.
7. The number of sample plots in the plot census needed to estimate the density of total bird species in 20-30ha woods with 95% confidence limit and 10% ±sample error against the average was regarded as 10-15. The desirable time to be spent in the plot was considered to be 2-5 minutes.

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The distribution of the Ryukyu Robin Erithacus komadori was investigated from field observations, museum skins, references and personal communications. The species is endemic to southwestern Japan, with a single specimen, a male, from Korea and one sight record from Taiwan. Many individuals have been observed in the northern Tokara Islands in the breeding season, but few remain in winter, while on the other hand, there are few records of the species in the southern, Yayeyama, islands, and all are from nonbreeding season. It seems that some of its northern populations would have migrated south in winter. The measurements and plumage characters described by Kuroda (1923) for his new form, subrufus, are not distinctive enough, in our comparison, from those of the race komadori. Furthermore, the type specimen of E. k. subrufus was collected in Yonakunijima in the migratory season, October. It is, therefore, condluded that the race subrufus is a synonym of komadori. The sporadic present distribution of the Ryukyu Robin reveals its recent relic status from its former more extensive distribution.

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Based on waterfowl censuses made on 17-18 December 1986 and 9-10 January 1987 on a highly eutrophic lake, Lake Teganuma, Chiba Prefecture, the patterns of distribution of the waterfowl were analyzed in relation to feeding habits and local water pollution. Thirteen species were recorded, with mean daily numbers totalling 1, 988±378 (SD) individuals. Spot-billed Duck Anas poecilorhyncha was most abundant representing 32.3% of total numbers, followed by Northern Pintail Anas acuta 17.6%, Mallard Anas platyrhynchos 16.2% and Common Teal Anas crecca 16.0%. More than 90% of these ducks used the lake as a diurnal resting area. However, although low, Northern Shoveler Anas clypeata, 10.8%, Smew Mergus albellus, 2.5% and Gadwall Anas strepera, 3.9%, fed during the day on food available in Teganuma; 40.7% of Anas clypeata foraged in the shallows where zooplankton, Copepoda Cyclops vicinus and Rotifera Brachionus calyciflorus and Filinia longiseta, occurred at high densities. 40.7% of Mergus albellus on the other hand fed in the central part of the lake, probably on a small fish ("motsugo") Pseudorasbora parva and the shrimp Macrobrachium nipponense, which survived in the polluted water, though they are low in biomass. Anas strepera was found to aggregate at the mouth of the Otsugawa river where there was an inflow of domestic sewage. 41.8% of this species was found feeding on sludge deposits.

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A male Blue Rock Thrush Monticola solitarius was caught and banded on Nakanoshima Island, Tokara Islans, Kagoshima Prefecture on 2 May 1988. On the basis of its plumage it was identified as being of the subspecies M. s. pandoo, the first time that this subspecies has occurred in Japan.

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It proved possible to sex Eastern Spot-billed Duck Anas poecilorhyncha zonorhyncha on the basis of plumage color; 43 males and 37 females were collected in Tochigi Prefecture in May, 1987, and their sex determined by dissection. Sexual differences were found in the upper and under tail-coverts, and belly. Males have lustrous black upper and under tail-coverts, and a deep rufous-black belly. Females have rufous-black upper and under tail-coverts with pale buff-brown fringes or spots, and a belly similar to the breast.

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Ten external morphological variables were obtained from four different kinds of specimens of Brown-eared Bulbul Hypsipetes amaurotis which differed both in capture site and in condition of storage. Almost all the variables were larger in males than in females, showing a pronounced sexual size dimorphism. The specimens kept as study skins differed in both means and variances of almost all of the variables from fresh or frozen specimens.
A discriminant function analysis was done for the specimens which had been collected from the same site in the same season. As a result, a discriminant function incorporating the lengths of tarsus, bill from nostril, total length, wing span, total head and width of bill at nostril could discriminate sex correctly at the probability of wrong discrimination of 0.021. Another two discriminant functions for more general situations were derived from an analysis of specimens collected from various sites, incorporating lengths of tail, tarsus, bill from nostril, wing span and total head, or the lengths of natural wing, tail, tarsus, exposed culmen and total head. We can use these functions for discriminating sex with an accuracy of 95%.
These functions correctly classified sex of only 74% of study skins, showing that they could not be reliably applied to these specimens.

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From 28 April-2 May 1989 we flew along rivers and over lakes and marshes in eastern Hokkaido, northern Japan, to detect the distribution and breeding status of the Tancho or the Red-crowned Crane Grus japonensis. Flying time was about 22.8 hours and the flight distance was about 3, 000km in total. Eight individuals were found incubating on nests in the Tokachi, 52 including a brooding pair in the Kushiro, 38 in the Nemuro, and none in the Abashiri Districts. The distribution pattern of these 98 nests was basically similar to those found in previous years, but some new nest sites were recorded and by contrast some previous known sites were found to have been destroyed by land development for agriculture. The shortest distance between 2 nests was about 400m and the average shortest one of all nests was 3, 101m (n=97). Only 233 individuals, just 56% of the wintering population, were observed from the air. Some of the cranes of Hokkaido are assumed to migrate to the Kurile Islands. It is clear that not one but a number of surveys is necessary to reveal the true distribution of this species' breeding grounds, with international exchange of information between the USSR and Japan.

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In October 1981, I surveyed a colony of the Streaked Shearwater Calonectris leucomelas on Toshima Island in the Izu Islands, Japan, in order to collect ectoparasites. The following ectoparasites were collected from 6 Streaked Shearwaters (4 adults, 2 downy chicks): Mallophaga: (1) Longimenopon shiraii, (2) Halipeurus sawadai, and Shiphonaptera: (3) Ceratophyllus hagoromo. These bird lice were found on their hosts' (1) breast and abdomen on downy chicks; (2) axillars, dorsal, and wings of adults and downy chicks; and (3) on an adult and a downy chick in the same nest.

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[in Japanese]

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Annual testicular activity was investigated in the Indian Tree Pie Dendrocitta vagabunda by studying the testis once a month throughout the year. The investigation revealed that testicular activity showed a distinct annual cycle consisting of four phases: nonbreeding (August to January); progressive (February and March); breeding (April and May); and regression (June and July). The testis weight, seminiferous tubular area and germ cell population were low during the nonbreeding phase, increased during the progressive phase, peaked during breeding and declined afterwards. But the sertoli cell population increased during the nonbreeding phase and decreased in the early breeding phase (April). The Leydig cells were large during the early breeding phase compared to other phases of the cycle. Cholesterol and ascorbic acid levels in the testis were highest during the nonbreeding phase, decreased moderately during the progressive phase, became lowest during the early breeding phase and began to rise thereafter. But acid phosphatase, alkaline phosphatase, sialic acid, RNA and protein content changes of the testis were the reverse. The findings indicate that the Indian Tree Pie has a single peak of spermatogenic activity in a year during April and May. Steroidgenic activity of the testis also varies with the spermatogenic cycle, but it appears to reach its peak slightly earlier in April than that of spermatogenic activity in this species.

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The female reproductive cycle was investigated in the Indian Tree Pie (Dendrocitta vagabunda) by studying the ovary once a month throughout the year. The ovarian activity showed a distinct annual cycle consisting of four phases: nonbreeding (August to January); progressive (February and March); breeding (April and May); and regression (June and July). The weight of the ovary and diameter of the largest follicle were smallest during the nonbreeding phase, partially increased during the progressive phase, peaked during breeding and decreased thereafter. The primordial and small developing follicles were present in the ovary throughout the year but large developing follicles appeared during April, May and June. Yolky and post-ovulatory follicles were found only during the breeding phase. The population of primordial follicles declined, followed by a rise in the population of small and large developing follicles with the appearance of yolky follicles, during the breeding phase as compared to those of other phases of the cycle. Cholesterol and ascorbic acid concentrations were highest during the nonbreeding phase, slightly declined during the progressive phase, became lowest during breeding and began to rise subsequently. But acid phosphatase, alkaline phosphatase, sialic acid, glycogen, RNA and protein levels were reversely altered. The findings indicate that the ovarian folliculogenesis as well as steroidal activity vary simultaneously with a peak in May during the breeding phase of the seasonal sexual cycle of the tree pie.

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The aim of the present investigation was to ascertain adrenaline and noradrenaline contents of the adrenal gland as well as blood glucose levels during the seasonal gonadal cycle in both sexes of the Indian Tree Pie Dendrocitta vagabanda. The investigation was carried out once a month throughout the year. The findings revealed that adrenal adrenaline and noradrenaline levels, and blood glucose levels decreased during the breeding phase in both sexes of birds. It is suggested that adrenomedullary hormonal levels are not directly related to the annual gonadal cycle, but that the glycemic level may have some relationship with the gonad in this species.

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This paper is described mainly for the reference of overseas banders or others who wish to know the bird-banding activities in Japan. At the beginning, the history of Japanese bird-banding is described in the three periods, the period before the War (1924-1945), the period of the Forestry Agency (1961-1971) and the period of the Anvironment Agency (1972-present). In the next part, the results of the national birdbanding shceme carried out for 1988 are abstracted and briefly described as to the numbers of birds banded, the notable banding records, the numbers of recoveries, the notable recovery records and longevity records revealed by bird-banding.

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Tadorna cristata (Kuroda) is known only from three extant specimens. The first, a female, was taken near Vladivostok in 1877, and preserved in the Copenhagen Museum. The second specimen, also a female, and the third specimen, a male, were taken from near Fusan, Korea in 1916, and 1913 or 1914, and preserved in the Yamashina Institute for Ornithology. The first specimen was described in 1890 by Sclater, and it was then considered to be a hybrid between the Ruddy Shelduck (Tadorna ferruginea) and the Falcated Duck (Anas falcata). In 1917, Dr. Nagamichi Kuroda described the second specimen and gave it the name Pseudotadorna cristata. The inconsistency between Sclater's hybrid view and Kuroda's new species view was solved in favor of the latter, when Kuroda obtained the third, male specimen, and described it, along with the discovery of four sketches of the Crested Shelduck from the Edo period. This species has been extremely rare, and close to extinction evre since its discovery in 1887. Recently three other old sketches of the Crested Shelduck have been reported, two of them by the present authors. In this paper twelve published sketches of the species from the Edo period have been introduced, and all twenty known sketches are arranged in order based on their characteristics and descriptions, and the status of it's occurrence during the Edo period is disccussed. In conclusion, we presumed that a few Crested Shelducks were imported from Kyohou period (1716-1735) and it actually migrated once or twice to Hokkaido (northern Japan), and was captured to be illustrated as a living bird.

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