Fecal estradiol levels in females of the migratory Reed Bunting Emberiza schoeniclus and non-migratory Meadow Bunting Emberiza cioides were measured by radioimmunoassay after extraction with ether. When the photoperiod conditions were changed stepwise from 10hr light/14hr darkness (LD 10:14) to LD 15:9, the fecal estradiol levels in the migratory Reed Bunting increased significantly at LD 12:12 and subsequently decreased at LD 14:10. A similar pattern of change was observed in the non-migratory Meadow Bunting. Fecal estradiol levels appear to reflect the levels circulating in plasma, indicating that estradiol levels circulating in plasma increase at LD 12:12 and subsequently decrease at LD 14:10 not only in the migratory Reed Bunting but also in the non-migratory Meadow Bunting.

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We examined the functional significance of learned acoustic structure in Budgerigars, a species of Psittaciformes in which vocal learning is common. We compared the acoustic structure of normal song to the song of males deafened early in life. The 'deaf song' differed from normal song in the structure of its component sounds. In playback experiments, normal male song elicited more song from male subjects than did the deaf song. The results are discussed in terms of the possible roles that learned acoustic structure plays in male-male communication among Budgerigars.

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We provide information on the onset of incubation, the involvement of males and females in incubation, and on the hatching pattern in the Rufous Vanga Schetba rufa of Madagascar. Rufous Vangas breed cooperatively with one to four one-year-old and/or adult auxiliary males. Large amounts of time were spent in incubation from the date the first-egg was laid. Breeding male Rufous Vangas took a much greater share of incubation during the laying period than did females, but males and females took almost equal shares during the incubation period. Females spent more time brooding their chicks than did males, however, males contributed more in terms of provisioning young chicks than did females. While the hatching pattern varied from perfectly asynchronous to perfectly synchronous, the fledging pattern was generally synchronous with all chicks in a given brood fledging on the same day. The nest failure hypothesis cannot explain the adaptive significance of early commencement of incubation in this species, because the incubation pattern was not a reliable predictor of the hatching pattern. As the daily ambient temperatures fluctuates greatly from 20°C to more than 35°C, it is likely that Rufous Vangas commence incubation on the day on which the first egg is laid in order to regulate egg temperature and to increase the hatchability of first-laid eggs. Males may take charge of incubation during the laying period because females must spend considerable time foraging in order to produce eggs. Dominant males, in cooperatively breeding groups, may spend considerable time incubating, despite the risk of cuckoldry by auxiliary males, in order to raise the rate of hatchability.

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A subspecies of the Brown Shrike, Lanius cristatus superciliosus, has undergone a severe decline in Hokkaido for the past three decades. I studied the reproductive performance and nestling growth during the breeding seasons in Hokkaido. I examined 41 active nests during 1992-1996. The mean nesting success was 53.7%. The mean clutch size was 5.3, and the mean number of eggs hatched per nest was 5.1. The mean number of fledglings per successful nest was 4.4, and the mean fledging success per successful nest was 90.3%. The main cause of nesting failure was depredation by unknown predators. The frequency of parasitization by Cuckoos, Cuculus canorus, was very low, and Brown Shrikes either removed the cuckoo egg or deserted their nest containing one Cuckoo egg. The gains of body mass and tarsus length for 75 nestlings from 15 nests (a total of 273 nestlings) were fitted to Ricklefs's logistic regression curves from the hatching day to 11 days after hatching. The asymptotic mass (g), growth rate, and age (days) at the inflection point were 27.1, 0.4, and 5.7, respectively. The asymptotic tarsus length (mm), growth rate, and age (days) at the inflection point were 24.9, 0.3, and 4.4, respectively.

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Chick growth and fledgling performance of Streaked Shearwaters (n=89 in total) were studied on Mikura Island (33°52'N, 139°14'E), Izu Islands, Japan, in 1985 and 1990. Chicks hatched in mid August (13^th, 17^th) on average, with a mean body mass of 59-73g (11-13% of 552g mean adult mass). Adults stayed with their chicks for four days on average after hatching. Exposed culmen, tarsus, and wing lengths of chicks at hatching were 42%, 38% and 8% of mean adult sizes of 49, 51 and 310mm, respectively. Chicks attained mean adult body mass at around 40 days old in mid September. Peak body masses (734-739g) were reached on average in mid October at around 70 days old, and were about 33-34% heavier than mean adult size. Weight recession prior to fledging resulted in the loss of 30% of the peak body mass over the last three weeks, and chicks fledged at body masses of 519-522g that did not significantly differ from the 508g mean adult or subadult masses in autumn. Individual chicks increased body mass in an erratic fashion at intervals of from a few days to a week throughout the nestling period. Body mass and bony parts (culmen and tarsus) attained maximum increase rates (13.8g, 1.0mm and 0.6mm/day, respectively) by days 9-22, while flight feathers as well and tail feathers that emerged at 39 days on average, grew most rapidly at about 62-75 days (3.0mm/day [for remiges] and 4.3mm/day [for rectrices]). Chicks fledged almost at adult sizes (adult body mass and lengths of culmen and tail, but with 2% shorter tarsus and wing than adults). All of the growth rate constants ks, were very low at 0.05 for body mass, exposed culmen and wing, and at 0.08 for tarsus (only the tail constant was higher). These low values were typical of semi-precocial birds. Last feeding of chicks by parents occurred when chicks were 82 days old (7 November) on average and chicks were not fed for nine days on average prior to fledging. The mean length of the nestling period was 90-91 days, which ended on 13-17 November on average. Fledging success rate for chicks that had hatched was very low (21%) at the colony near the garbage dump, compared with two other areas with less human activity (68-72%). Most chicks were lost due to predation by feral cats and rats.

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We examined the cost-benefit patterns of strategies used by Silvereyes initiating aggressive encounters against unfamiliar opponents at a localized food source. We recorded initiator behaviour of individually colour-banded birds at a feeding station on Heron Island, Great Barrier Reef, and found that, in crowded conditions where most fighting occurred indiscriminately, initiators used more threat elements than attack elements and that dominant and lower-ranking birds did not differ in their strategies when initiating encounters. This is in contrast to more attack-oriented initiator behaviour of captive birds fighting against familiar opponents. Between familiar members the initiator would use different strategies according to the rank of the opponent relative to the initiator. Our results indicated that birds fighting unfamiliar opponents would adopt strategies similar to those used against higher ranks by captive silvereyes, supporting the prediction of the cost-benefit hypothesis in agonistic encounters.

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We examined the degree of intraspecific differentiation of the mitochondrial cytochrome b gene (Cytb) of the Jungle Crow, Corvus macrorhynchos, in East and South Asia. We determined partial sequences of Cytb (336 base pairs in length) for 41 individuals from this region. A neighbor-joining phylogenetic tree based on the Cytb sequences showed four obvious haplotype groups: 1) the Russian Far East and northern Sakhalin, 2) southern Sakhalin and the Japanese islands excluding the Ryukyus, 3) Amamioshima, the Ryukyus and 4) Laos. These Cytb clusters were fundamentally similar to the morphological differentiation and existing classification of Jungle Crow subspecies. Thus, we concluded that genetic material was probably interchanged among Jungle Crow groups even with geographic isolation due to the presence of a strait or gulf between land areas. In some cases, haplotypes and corresponding subspecies appear to be distinct even without the help of visible geographic barriers. Such subdivision probably occurred in Sakhalin because of the different ways in which this island was populated.

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The food habits of Hazel Grouses Bonasa bonasia were analyzed based on crop contents of 237 birds shot from early October to late January in 1994/95 and 1995/96 and from February to September 1996 in Hokkaido, Japan. Crop contents were greater in December and January than in October and November. Considerable seasonal variation in major food items was observed: buds of deciduous broad-leaved trees from November to February; leaves of herbaceous plants during the snow-free season; seeds during June and July, and fruits from October to January. In addition to these food items, arthropods were eaten frequently, although in small amounts, in June and July. Although the food habits of this species are basically similar in both Europe and Hokkaido, in Hokkaido the buds of a wider range of tree species were eaten in winter and the fruits of lianas such as Vitis coignetiae and Actinidia arguta were important foods during autumn and winter in Hokkaido.

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The fate of captive-bred Copper Pheasants Syrmaticus soemmerringii released in Tochigi Prefecture, eastern Japan, in order to restore the wild population, was investigated based on mark and recapture information, on hunting data and by radio tracking. From 1989 to 1997, the recapture rate of all released individuals was 1.3%. Most recovered Copper Pheasants were hunted within one hunting season after their release. Only 0.3% of all released individuals were recaptured beyond two hunting seasons. The extremely short longevity (average 11.4 days after release) of released birds was confirmed by radio tracking in Tochigi Prefectural Citizen's Park. Distances between release and recovery points averaged 14.6km, but some individuals moved more than 40km, and one 87km. Our results show that it is difficult to achieve population recovery using current methods. Based on our experience, we propose various improved release methods, including: changing the release points of males from refuges to hunting areas, and releasing females just before the breeding season.

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The number of observed species is an index of the relative value of the site to be protected in relation to other sites. To date, most analyses pertaining to species richness have focused on breeding populations and sites. However, avian migratory bottlenecks are no less important for conservation and management purposes. Here we present an example with the use of bird ringing conducted at Eilat, Israel, between the years 1984-2000. We hypothesized that because Israel is located at the juncture of the three continents, we will have new species every year. During the 17 years, 139, 354 individuals of 268 species were ringed. The average of total birds ringed per year was 8197.3 and the average number of species was 113. Of 268 species ringed, 205 (76.5%) were passage migrants, 41 (15.3%) breeding species, and 22 (8.2%) were accidentals. We found a significantly positive correlation (r²=0.857, P=0.014) between the number of species caught each year and the number of operational net days. The number of species recorded annually correlated significantly with the number of individuals caught and the cumulative number of recorded species increased logarithmically throughout the study period. The greatest increase was recorded between the first and second years. Changes in the number of new species decreases non-significantly over the study period. Further, when the difference between the first and the second year is removed this relation is non-significant. It means that chances to catch new species for Eilat are always the same. In conclusion, a ringing station can expect to catch the largest proportion of species within the first three years of activity and then to catch two to three new species annually, i. e., at Eilat we should expect to catch 20 new species during the upcoming decade.

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Banding research was conducted at Otayama Banding Station (Fukui Prefecture, central Japan) for 24 years (from 1973 to 1996) from mid October to early November. In order to be able to compare annual variation in species and numbers, the same numbers of mist nets was set at the same locations each year. In total 71, 416 individuals of 75 species were captured and banded. The ten commonest species banded were: Emberiza rustica, Emberiza spodocephala, Zosterops japonica, Turdus pallidus, Phylloscopus borealis, Turdus obscurus, Cettia diphone, Parus major, Turdus naumanni and Fringilla montifringilla, and they amounted to 90% of the total number of birds banded. The two most commonly banded species, E. rustica and E. spodocephala, contributed 53% of the banding total. Each year 21-54 species were caught (average 40.0) and 16 of these species were caught every year. The average number of birds banded per day was compared from year to year for the 17 day period from 20 October to 5 November. Annual variation in the number of birds banded included: (1) Species Declining (9 species, including E. rustica, Z. japonica, and F. montifringilla); (2) Species Increasing (2 species, E. spodocephala and T. cardis); (3) Stable Species (10 species including P. borealis, Aegithalos caudatus, and Ficedula mugimaki), (4) Species Showing Annual Fluctuations (4 species including Pyrrhula pyrrhula, Tarsiger cyanurus, and Ficedula narcissina). Comparison with other locations indicates that deforestation appears to have influenced the numbers of E. rustica and E. spodocephala. More conspicuously, species and numbers banded have fallen by about half from 22, 290 individuals of 58 species during the 1970s to 11, 865 individuals of 49 species during the 1990s. The banding records of three species, E. rustica, F. montifringilla and T. naumanni, have fallen by the 1990s to just ten percent of numbers during the 1970s. In contrast, both E. spodocephala and T. obscurus were more commonly banded during the 1990s than during the 1970s. The forest around the Otayama Banding Station was largely felled during the 1970s. This deforestation altered the surroundings, altered species and bird numbers, however the extent of these changes varied from species to species. In general, however, deforestation reduced species diversity.

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Forty-four cases of breeding (including breeding attempts) of the Common Kingfisher, Alcedo atthis, were recorded in the Imperial Palace Grounds and the Akasaka Imperial Grounds, both in Tokyo, during the period from 1990 to 2001. From 1992 on, both breeding individuals and fledglings were banded and monitored. It was found that during each breeding season there were two pairs of breeding individuals in the Palace Grounds and one pair in the Akasaka Grounds. Of these, one pair was inferred to have bred for two consecutive years or more, and several individuals for three to four consecutive years. One male moved to the Akasaka Grounds after having bred in the Palace Grounds, and bred there again in the same breeding season. The distance between two simultaneously active breeding nests in the Palace Grounds was 100-180m. The shortest distance observed here was much shorter than any other so far reported for Japan and Europe. This fact, coupled with the presence of presumably non-breeding adults during the breeding season at the two sites suggests that the creation of new breeding sites attracts more breeding individuals to the Palace and Akasaka Grounds. The mean brood size and mean number of fledglings for the two sites were 6.44 and 6.23, respectively. There is only a slight difference between the two values, and both are similar to those hitherto reported in Japan and Europe. On the basis of these observations, it is likely that the loss of eggs and chicks in the nests is small. Breeding activity of two individuals banded in this study was observed outside the study sites. In one case a male that bred in the Palace Grounds in 1996 and 1997 bred three times in Kanayama Ryokuchi Park in Kiyose, Tokyo, about 24km from the Palace, in 2000 and 2001. In the second case an individual which was judged to have fledged or bred in the research area displayed courtship feeding behavior in the inner garden of Meiji Shrine, about 2km west of the Akasaka Grouds, in 2001.

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From January 1975 to January 1977, we observed the feeding behavior of Kentish Plovers at the Obitsu estuary (35°24'N, 139°54'E) in Tokyo bay. This area is one of the most important staging sites for migratory shorebirdsin Honshu, and a valuable feeding site for the Kentish Plovers. During daytimeand at low tide, they spent an average of 86.4% of observation time for feeding. After mid December, their feeding rate increased and their resting rate decreased. Scopimera globosa, Nereidae and Capitellidae are the main prey of Kentish Plover here. Brachyura constituted 39.8-66.3% of the diet, but only 7.2-10.8% of the benthos, clearly showing that Kentish Plover positively selects Brachyura as prey.

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The distribution of the Okinawa Rail Gallirallus okinawae was studied, using the voice play back method, at 296 sites in 1996-1999 and at 564 sites in 2000-2001, in the northern part of Okinawa Island. The results were plotted on a 1.25km×0.925km map grid. The presence of Okinawa Rails was confirmed at 49 out of 95 grid intersections (51.6%) during 1996-1999 and at 116 out of 255 grid intersections (45.5%) in 2000-2001. These results were compared with similar research undertaken by the Environmental Agency in 1985-1986. This comparison indicates that the border of the species' range has shifted north by about 10km over the past 15 years, resulting in a 25% decrease in the range of this species.
Between 2 October 2000 and 30 March 2001 Okinawa Prefectural Government carried out controls of the introduced mongoose Herpestes javanicus in northern Okinawa Island using approximately 800 traps located at a total of 2, 470 sites. A total of 303 mongoose were caught, mainly in the southern area from which Okinawa Rails have disappeared in recent years. The result of rail population mapping and of mongoose trapping strongly imply that the mongoose has caused the range contraction of the Okinawa Rail. We believe that urgent conservation measures are required in order to prevent this species from becoming extinct.

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Longlining is one of the major fishing techniques used to capture pelagic and demersal fish. The incidental take of seabirds in longline fisheries has become a concern to fishing states, biologists, and conservationists in recent years. Most of the incidental take occurs during line setting, when sea birds are attracted to the baited hooks drifting near the sea surface astern of the fishing vessels. Large surface-scavenging seabirds (particularly albatrosses and large petrels) are caught in longline operations mostly in the temperate and subpolar waters. The issue first emerged in the Southern Ocean in the 1980s and 1990s, and management measures were considered by the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR) and the Convention for the Conservation of Southern Bluefin Tuna (CCSBT). Measures to reduce the incidental take or bycatch of seabirds have been developed taking advantage of the behavioral characteristics of albatrosses and large petrels. The mitigation measures currently available include: 1) bird scaring devices using streamer lines, sounds and water, 2) increasing the sinking rate of baited-hooks by weighting them, 3) underwater setting of lines, 4) line setting at night, 5) decreasing the attractivity or visibility of baits, 6) control of offal and discards. Since most of the mitigation measures improve fishing efficiency by reducing bait loss to seabirds, fishers are ready to adopt a mitigation measure if it is safe and cost-effective. Fishing states are implementing outreach programs for education and enlightenment of fishers and of the general public as well as developing mitigation techniques. In 1999, the FAO promoted the International Plan of Action for Reducing Incidental Catch of Seabirds in Longline Fisheries. In agreement with the FAO International Plan, and its Code of Conduct for Responsible Fisheries, each fishing state is required to develop its own National Plan of Action and expected to make efforts towards reducing seabird mortality in fisheries, if those fisheries are causing incidental takes of seabirds. International efforts are also necessary to prevent and eliminate illegal, unregulated, and unreported fishing.

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Most of the range of the Whooper Swan Cygnus cygnus falls within the borders of Russia and the associated republics. Although most research on this species has been conducted in Europe and Japan, a growing body of work has been developed since 1980 in Russia. As this work has mostly appeared only in Russian, and often in local journals, the accessibility and availability of that literature to non-Russian scientists has been extremely limited. We have compiled and reviewed the Russian literature, as it pertains to this species, from four regions. We have also attempted to give an overview of the populations, their breeding biology, wintering range, migration, and moulting behaviour in: 1) Western Russia (west of the Ural Mountains), 2) Western Siberia (east of the Urals and west of the Yenisei River, 3) Central and Eastern Siberia (from the Yenisei to the Lena), and 4) The Russian Far East (from the Lena to the Bering Sea). Each of these four regions is as large, or considerably larger than the area occupied by the European population, which is currently the only region for which accurate information on population size is available.
The Whooper Swan population in Russia is large, generally secure, and seemingly expanding its range northwards. It suffers from a wide range of anthropogenic influences, including disturbance, habitat degradation, habitat loss, and hunting, but in some areas is also re-occupying breeding haunts where such negative influences have declined. The Whooper Swan ranges in Russia from the Kola Peninsula in the northwest east to the Anadyr Valley of Chukotka and to Kamchatka. The northern limit to its range lies close to 67°-68°N. There is circumstantial evidence for a continued general expansion of its breeding range northwards. The breeding range extends south to 62°N in western parts of European Russia, but as far south as 55°N to 50°N in Sakhalin and Kamchatka. It winters south to 47°-50°N in the west, however its southernmost wintering grounds are in Japan where for climatic reasons it can be found in large numbers at latitudes as low as between 35°N and 40°N. In Russia, the Whooper Swan is a breeding bird of the northern taiga, of forest-tundra, and in some places of the tundra too. Human influences during the mid 20^th century have, in some areas, particularly in the west, greatly reduced the Whooper Swan's population and range below 19^th century and early 20^th century levels. Over the latter part of the 20^th century, however, it has begun to re-occupy its former range. Population estimates vary enormously even for the same regions making overall estimation of the population virtually impossible. For example estimates for Western Russia and Western Siberia range from as few as 10, 000 to more than 100, 000 (Ravkin 1991, Rees et al. 1997). There is considerable room for further research in this the largest portion of the Whooper Swan's range. The population of the Russian Far East is thought likely to be in the region of 60, 000 birds based on numbers wintering in Kamchatka, Japan, the Korean Peninsula and China.
Although the majority of the Whooper Swan's world population breeds in Russia, most of these birds migrate to areas beyond Russian borders to winter in adjacent countries, around the Baltic Sea, the Caspian Sea, and the Sea of Japan. The timing of migration varies from region to region, but in autumn at least does seem largely driven by sharp falls in temperature, particularly of daytime temperatures from 5°C to 0°C. Evidence from widely different areas in Russia point to spring and autumn migration taking place in different waves. In spring, pairs and families predominate among early migrants, nonbreeders among later migrants.

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An understanding of the infectious and parasitic avian disease organisms that are present in Japan and surrounding areas is an essential conservation tool. This paper provides an overview of infectious and parasitic avian disease organisms (e. g. viruses, bacteria, fungi, protozoa, helminths, arthropods), and outlines and discusses briefly potential strategies for risk reduction.

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Ticks often carry infectious pathogens, and ticks infected with pathogens can be transmitted to seabirds. In May 1999, a project team member contracted a fever after being bitten by a tick during a field survey of albatrosses on Tori-shima. The researcher was bitten while in the main part of the Black-footed Albatross D. nigripes colony. Serodiagnosis indicated that the patient had been affected with borreliosis. The tick species involved was collected on Tori-shima and identified (based on its morphology) as the soft tick Carios (Ornithodoros) capensis.
A survey was carried out on Tori-shima in March and May 2000 in order to isolate the spirochete from the soft tick C. (O.) capensis, the host albatross D. nigripes and the Roof Rat Rattus rattus. We were unable to isolate Borrelia from either C. (O.) capensis, from blood or from the skin of the underside of the feet of D. nigripes, or from the ears or bladder of R. rattus. Nevertheless, ticks can be a negative factor affecting seabird reproduction. We report on the ecological status of C. (O.) capensis on Tori-shima, describe the relationship between this tick species and the various host animals on the island, and propose that surveys for ticks in seabird breeding colonies are very importance.

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