Katsura Mikami, Noriyuki M. Yamaguchi, R. Noske, Kazuhiro Eguchi
Abstract We studied the pattern of acquisition of breeding positions among helpers in a population of Grey-crowned Babblers Pomatostomus temporalis rubecula in the monsoon tropics of northwestern Australia, using both behavioural and molecular data. In particular, we focused on sex differences, kinship, and their interactions among emigrating helpers. Moreover, we also considered whether intergroup movement and extra-pair mating contributed to incest avoidance in our population. The advantage of this material is that there are previous studies of populations in different regions, and the comparison of the results may provide a better understanding of ecological factors driving helping behaviour in cooperative breeding. Three options for a mature helper to acquire a breeding position were observed: establishing a new territory, emigrating to an existing territory, or waiting in the natal territory for a breeding vacancy. In many cases, male helpers took the third option, while female helpers took the second one. Our population of Grey-crowned Babblers seemed not to be actively avoiding incest. Female helpers tended to disperse from natal groups more than males, but neither intergroup movements nor extra-pair mating were effective in avoiding incestuous breeding. In some groups, dominant breeders were closely related to each other. The frequency of extra-pair mating in our population was similar to that of the New South Wales population previously studied, but dispersal distances were twice as great. The two populations also differ in mean clutch size and group size. Such variation in life history characteristics among different populations of cooperatively breeding species has received little attention, but has the potential to explain how cooperative breeding systems are modified by environmental factors.
{"title":"Male and Female Helpers of Grey-Crowned Babblers Pomatostomus temporalis rubecula Acquire Breeding Positions in Different Ways, and don't Avoid Incest","authors":"Katsura Mikami, Noriyuki M. Yamaguchi, R. Noske, Kazuhiro Eguchi","doi":"10.2326/osj.20.3","DOIUrl":"https://doi.org/10.2326/osj.20.3","url":null,"abstract":"Abstract We studied the pattern of acquisition of breeding positions among helpers in a population of Grey-crowned Babblers Pomatostomus temporalis rubecula in the monsoon tropics of northwestern Australia, using both behavioural and molecular data. In particular, we focused on sex differences, kinship, and their interactions among emigrating helpers. Moreover, we also considered whether intergroup movement and extra-pair mating contributed to incest avoidance in our population. The advantage of this material is that there are previous studies of populations in different regions, and the comparison of the results may provide a better understanding of ecological factors driving helping behaviour in cooperative breeding. Three options for a mature helper to acquire a breeding position were observed: establishing a new territory, emigrating to an existing territory, or waiting in the natal territory for a breeding vacancy. In many cases, male helpers took the third option, while female helpers took the second one. Our population of Grey-crowned Babblers seemed not to be actively avoiding incest. Female helpers tended to disperse from natal groups more than males, but neither intergroup movements nor extra-pair mating were effective in avoiding incestuous breeding. In some groups, dominant breeders were closely related to each other. The frequency of extra-pair mating in our population was similar to that of the New South Wales population previously studied, but dispersal distances were twice as great. The two populations also differ in mean clutch size and group size. Such variation in life history characteristics among different populations of cooperatively breeding species has received little attention, but has the potential to explain how cooperative breeding systems are modified by environmental factors.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"20 1","pages":"3 - 13"},"PeriodicalIF":0.6,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46602232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Research into the breeding ecology of birds is key to understanding the evolution of life-history traits and developing effective species conservation measures. We studied the breeding ecology of the Crested Myna Acridotheres cristatellus on tropical Hainan Island, China, throughout the breeding season from March to August in 2018 and 2019. Parents Crested Myna build disk-shaped nests together and take turns to incubate their eggs and feed their nestlings, with a nestling period of 18–22 days. Eggs were pure blue-green, and the clutch sizes were 3–6 eggs (averaging 4). Egg mass, egg size, and egg volume were 6.78±0.50 g, 28.74±1.20 mm×21.13±0.53 mm, and 6.56±0.50 cm3, respectively (N=274). Egg-laying mainly occurred between 0700 to 1000, and the average time for laying one egg was 172.36±28.29 s (N=11). Feeding frequency during the mid-nestling period was significantly higher than in the early periods (N=55). The Crested Myna population on tropical Hainan nested earlier, laid eggs earlier and had a longer breeding period than populations in the temperate zone.
{"title":"The Breeding Ecology of the Crested Myna Acridotheres cristatellus on Tropical Hainan Island","authors":"Jinmei Liu, W. Liang","doi":"10.2326/osj.20.83","DOIUrl":"https://doi.org/10.2326/osj.20.83","url":null,"abstract":"Abstract Research into the breeding ecology of birds is key to understanding the evolution of life-history traits and developing effective species conservation measures. We studied the breeding ecology of the Crested Myna Acridotheres cristatellus on tropical Hainan Island, China, throughout the breeding season from March to August in 2018 and 2019. Parents Crested Myna build disk-shaped nests together and take turns to incubate their eggs and feed their nestlings, with a nestling period of 18–22 days. Eggs were pure blue-green, and the clutch sizes were 3–6 eggs (averaging 4). Egg mass, egg size, and egg volume were 6.78±0.50 g, 28.74±1.20 mm×21.13±0.53 mm, and 6.56±0.50 cm3, respectively (N=274). Egg-laying mainly occurred between 0700 to 1000, and the average time for laying one egg was 172.36±28.29 s (N=11). Feeding frequency during the mid-nestling period was significantly higher than in the early periods (N=55). The Crested Myna population on tropical Hainan nested earlier, laid eggs earlier and had a longer breeding period than populations in the temperate zone.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"20 1","pages":"83 - 92"},"PeriodicalIF":0.6,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46544293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Son, Kisup Lee, In-Ki Kwon, Jung-Hoon Kang, Sung-Kyung Lee, In-kyu Kim, Hae-jin Cho, Jeong-Chil Yoo
Abstract Long-term population monitoring is very important for the conservation of threatened and endangered species. The Black-faced Spoonbill Platalea minor is a globally endangered species and the majority of its population breed on uninhabited islands off the west coast of the Korean Peninsula. The Chilsan Archipelago in the southwest is the southernmost breeding site for this species in Korea and is expected to help buffer the potential dispersal of Black-faced Spoonbills from breeding populations currently concentrated in the Gyeonggi Bay area. As there has been a lack of information regarding the number of Black-faced Spoonbills, their characteristics, and their recent population trends, the present study investigated the population trends of Black-faced Spoonbills breeding in the Chilsan Archipelago. The study, from 2014 to 2018, examined breeding success in 2015 and 2018, and the size and location of nests in 2018. The number of nests ranged from 43 to 163 (2014, 43; 2015, 93; 2016, 84; 2017, 85; 2018, 163). The percentage of birds that attempted breeding between April and May was 84.9% in 2015 and 87.1% in 2018, while the breeding success rate was 69.9% in 2015 and 81.5% in 2018. The average nest size in 2018 was 55.06±6.09 cm long and 53.44±6.56 cm wide, while the average surface slope below the nest was 25.42±6.95°. In total, nine plant species were used as vegetation for nests. During the present study, the environmental conditions and the presence of anthropogenic disturbances seemed to affect breeding success. Therefore, strictly controlled access to breeding sites and effective management are needed to protect and conserve breeding populations of this endangered species.
{"title":"Black-Faced Spoonbill Platalea minor Population Trends, Breeding Success, and Nest Characteristics in the Chilsan Archipelago, South Korea","authors":"S. Son, Kisup Lee, In-Ki Kwon, Jung-Hoon Kang, Sung-Kyung Lee, In-kyu Kim, Hae-jin Cho, Jeong-Chil Yoo","doi":"10.2326/osj.20.57","DOIUrl":"https://doi.org/10.2326/osj.20.57","url":null,"abstract":"Abstract Long-term population monitoring is very important for the conservation of threatened and endangered species. The Black-faced Spoonbill Platalea minor is a globally endangered species and the majority of its population breed on uninhabited islands off the west coast of the Korean Peninsula. The Chilsan Archipelago in the southwest is the southernmost breeding site for this species in Korea and is expected to help buffer the potential dispersal of Black-faced Spoonbills from breeding populations currently concentrated in the Gyeonggi Bay area. As there has been a lack of information regarding the number of Black-faced Spoonbills, their characteristics, and their recent population trends, the present study investigated the population trends of Black-faced Spoonbills breeding in the Chilsan Archipelago. The study, from 2014 to 2018, examined breeding success in 2015 and 2018, and the size and location of nests in 2018. The number of nests ranged from 43 to 163 (2014, 43; 2015, 93; 2016, 84; 2017, 85; 2018, 163). The percentage of birds that attempted breeding between April and May was 84.9% in 2015 and 87.1% in 2018, while the breeding success rate was 69.9% in 2015 and 81.5% in 2018. The average nest size in 2018 was 55.06±6.09 cm long and 53.44±6.56 cm wide, while the average surface slope below the nest was 25.42±6.95°. In total, nine plant species were used as vegetation for nests. During the present study, the environmental conditions and the presence of anthropogenic disturbances seemed to affect breeding success. Therefore, strictly controlled access to breeding sites and effective management are needed to protect and conserve breeding populations of this endangered species.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"20 1","pages":"57 - 64"},"PeriodicalIF":0.6,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46743431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract From December 2018 to December 2019, four nocturnal roosting sites with large aggregations of White Wagtails Motacilla alba were found in Haikou, Hainan, southern China. Three of them were located near road intersections in the city center of Haikou, and one was located at an airport terminal. Numbers of individuals exceeded 1,250 individuals at each roost. Characteristics of the environment and the nocturnal roosting trees were measured to elucidate the nocturnal roost preferences of white wagtails in urban areas, and some assistance was provided to the issues of urban greening and wildlife problems in cities.
{"title":"Sleeping in a Noisy World: Roosting Sites of Large Aggregations of White Wagtails Motacilla alba in a Tropical City, China","authors":"Xingyi Jiang, Changjie Zhang, Bo Zhou, W. Liang","doi":"10.2326/osj.20.109","DOIUrl":"https://doi.org/10.2326/osj.20.109","url":null,"abstract":"Abstract From December 2018 to December 2019, four nocturnal roosting sites with large aggregations of White Wagtails Motacilla alba were found in Haikou, Hainan, southern China. Three of them were located near road intersections in the city center of Haikou, and one was located at an airport terminal. Numbers of individuals exceeded 1,250 individuals at each roost. Characteristics of the environment and the nocturnal roosting trees were measured to elucidate the nocturnal roost preferences of white wagtails in urban areas, and some assistance was provided to the issues of urban greening and wildlife problems in cities.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"20 1","pages":"109 - 113"},"PeriodicalIF":0.6,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45728915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Mountains harbour high biodiversity that is facing a crisis due to recent climate change. Bird communities shift along mountain gradients. Some previous studies have suggested that the effect of vegetation is prevalent on temperate mountains. In this study, we investigated the limiting effects of vegetation on the altitudinal distribution of birds on Mount Norikura in central Japan, by comparing bird communities along four gradients of different orientations. We recorded birds using the line-transect method and classified vegetation into six types: montane deciduous broadleaved forest, subalpine coniferous forest, subalpine birch forest, Japanese Stone Pine scrub forest, alpine tundra and bare ground below the alpine area. We identified the treelines and ecotones between the predominant vegetation types along each gradient. We found that bird species composition changed drastically at the treeline along three gradients. A non-metric multidimensional scaling (NMDS) ordination revealed: 1) the similarity between bird community structures in the subalpine coniferous forest and the Japanese Stone Pine scrub forest differed among the gradients, 2) despite birch being broadleaved, the bird community in the subalpine birch forest was a subset of that in the subalpine coniferous forest and was more similar to that in the subalpine coniferous forest than that in the montane deciduous broadleaved forest, and 3) in upper parts of the subalpine zone, the bird community structures in the subalpine coniferous and birch forests were similar to each other. Our findings suggest that although the treeline limits the distribution of forest-dwelling bird species, this effect differs among gradients with different orientations, probably depending on the scrub height of the Japanese Stone Pine scrub forests. Furthermore, the heterogeneity of coniferous and birch forests in the upper parts of the subalpine zone may have little effect on the altitudinal distribution of birds.
{"title":"Bird Community Heterogeneity Along Four Gradients of Different Orientations on a Temperate Mountain","authors":"Daichi Iijima, G. Morimoto","doi":"10.2326/osj.20.65","DOIUrl":"https://doi.org/10.2326/osj.20.65","url":null,"abstract":"Abstract Mountains harbour high biodiversity that is facing a crisis due to recent climate change. Bird communities shift along mountain gradients. Some previous studies have suggested that the effect of vegetation is prevalent on temperate mountains. In this study, we investigated the limiting effects of vegetation on the altitudinal distribution of birds on Mount Norikura in central Japan, by comparing bird communities along four gradients of different orientations. We recorded birds using the line-transect method and classified vegetation into six types: montane deciduous broadleaved forest, subalpine coniferous forest, subalpine birch forest, Japanese Stone Pine scrub forest, alpine tundra and bare ground below the alpine area. We identified the treelines and ecotones between the predominant vegetation types along each gradient. We found that bird species composition changed drastically at the treeline along three gradients. A non-metric multidimensional scaling (NMDS) ordination revealed: 1) the similarity between bird community structures in the subalpine coniferous forest and the Japanese Stone Pine scrub forest differed among the gradients, 2) despite birch being broadleaved, the bird community in the subalpine birch forest was a subset of that in the subalpine coniferous forest and was more similar to that in the subalpine coniferous forest than that in the montane deciduous broadleaved forest, and 3) in upper parts of the subalpine zone, the bird community structures in the subalpine coniferous and birch forests were similar to each other. Our findings suggest that although the treeline limits the distribution of forest-dwelling bird species, this effect differs among gradients with different orientations, probably depending on the scrub height of the Japanese Stone Pine scrub forests. Furthermore, the heterogeneity of coniferous and birch forests in the upper parts of the subalpine zone may have little effect on the altitudinal distribution of birds.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"20 1","pages":"65 - 82"},"PeriodicalIF":0.6,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49545565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The adaptive mate choice theory is believed to provide a general explanation of sexual selection. Females are thought to choose males based on direct benefits or because they have perceivably good genes based on visual indicators of male quality, involving adaptive qualities acted on by natural selection in the current environment. However, a recent hypothesis, called “Beauty Happens” has been proposed based on Darwin's “Really Dangerous Idea,” an idea that has been criticised, to explain sexual selection in animals, including human beings. Accordingly, it has garnered widespread attention and evoked controversial debate. Here, I review the Beauty Happens hypothesis and clarify the arguments that focus on the sexual autonomy and aesthetic perception of females. I found that, in the case of sexually dimorphic birds, unambiguous evidence is absent in support of the adaptive mate choice theory. Although the Beauty Happens hypothesis is logically feasible, aesthetic perception could possibly evolve and develop on the basis of sexual autonomy and resource-independence in females. Therefore, aesthetic radiation among females may lead to beauty radiation in males, and female mate choice as a selection process may act independently of natural selection, favouring good-to-pass-on genes rather than good genes. However, the Beauty Happens hypothesis seems to be more applicable when explaining the behaviour of sexually dimorphic birds than other animal taxa. I suggest that the mechanisms of female mate choice and intrasexual competition in males may lead to biological evolution, depending on the degree of autonomy of females in different animal species.
{"title":"Is Aesthetic Evolution Possible in Birds? —Conceptual Considerations","authors":"Canchao Yang","doi":"10.2326/osj.20.101","DOIUrl":"https://doi.org/10.2326/osj.20.101","url":null,"abstract":"Abstract The adaptive mate choice theory is believed to provide a general explanation of sexual selection. Females are thought to choose males based on direct benefits or because they have perceivably good genes based on visual indicators of male quality, involving adaptive qualities acted on by natural selection in the current environment. However, a recent hypothesis, called “Beauty Happens” has been proposed based on Darwin's “Really Dangerous Idea,” an idea that has been criticised, to explain sexual selection in animals, including human beings. Accordingly, it has garnered widespread attention and evoked controversial debate. Here, I review the Beauty Happens hypothesis and clarify the arguments that focus on the sexual autonomy and aesthetic perception of females. I found that, in the case of sexually dimorphic birds, unambiguous evidence is absent in support of the adaptive mate choice theory. Although the Beauty Happens hypothesis is logically feasible, aesthetic perception could possibly evolve and develop on the basis of sexual autonomy and resource-independence in females. Therefore, aesthetic radiation among females may lead to beauty radiation in males, and female mate choice as a selection process may act independently of natural selection, favouring good-to-pass-on genes rather than good genes. However, the Beauty Happens hypothesis seems to be more applicable when explaining the behaviour of sexually dimorphic birds than other animal taxa. I suggest that the mechanisms of female mate choice and intrasexual competition in males may lead to biological evolution, depending on the degree of autonomy of females in different animal species.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"20 1","pages":"101 - 107"},"PeriodicalIF":0.6,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44545966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract We examined brood patch development, sex ratios, and morphological traits of 30 Ancient Murrelets Synthliboramphus antiquus captured from the nocturnal at-sea congregation off Teuri Island, Hokkaido, Japan during late May to early June 2016. Molecular sexing determined that 12 of the murrelets were males and 18 were females. The proportions of murrelets with brood patches (an indicator of breeding status) were similar for males (58%) and females (56%). Breeding murrelets were heavier than non-breeding murrelets. Males had deeper bills and longer heads than females, but their weights, wings, culmens, tarsi, bill widths, and skull widths were similar.
{"title":"Breeding Status and Sex Ratio of Ancient Murrelets Captured in the Nocturnal At-Sea Congregation Off Teuri Island, Japan","authors":"Shin Matsui, D. Whitworth, N. Sugita, I. Nishiumi","doi":"10.2326/osj.19.203","DOIUrl":"https://doi.org/10.2326/osj.19.203","url":null,"abstract":"Abstract We examined brood patch development, sex ratios, and morphological traits of 30 Ancient Murrelets Synthliboramphus antiquus captured from the nocturnal at-sea congregation off Teuri Island, Hokkaido, Japan during late May to early June 2016. Molecular sexing determined that 12 of the murrelets were males and 18 were females. The proportions of murrelets with brood patches (an indicator of breeding status) were similar for males (58%) and females (56%). Breeding murrelets were heavier than non-breeding murrelets. Males had deeper bills and longer heads than females, but their weights, wings, culmens, tarsi, bill widths, and skull widths were similar.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"19 1","pages":"203 - 209"},"PeriodicalIF":0.6,"publicationDate":"2020-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44080817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Long-distance bird migration is often characterized by a number of flight bouts interspersed with intermittent stopover periods for re-fuelling. However, little is known about the stopover ecology of songbirds migrating along the East Asian flyway. The aim of this study was to estimate the minimum stopover duration and body mass change during stopover of Red-flanked Bluetail Tarsiger cyanurus and Yellow-browed Warbler Phylloscopus inornatus based on 6,073 ringed and 502 re-captured birds during spring and autumn migration in the Russian Far East. For Red-flanked Bluetail the minimum stopover duration averaged 3.4 days in autumn and 1.7 days in spring, while for Yellow-browed Warbler it was 3.2 days in autumn and 2.1 days in spring. Significant differences in stopover duration were found between seasons, but not between the two species. The body mass of Red-flanked Bluetails significantly increased during stopover in spring and autumn, but no significant body mass changes were detected in Yellow-browed Warblers. The shorter minimum stopover duration of both species in spring may indicate a faster migration than in autumn, suggesting a time-minimizing strategy in spring to reach the breeding grounds as fast as possible.
{"title":"Stopover Duration and Body Mass Change of Two Siberian Songbird Species at a Refuelling Site in the Russian Far East","authors":"L. Bozó, T. Csörgő, W. Heim","doi":"10.2326/osj.19.159","DOIUrl":"https://doi.org/10.2326/osj.19.159","url":null,"abstract":"Abstract Long-distance bird migration is often characterized by a number of flight bouts interspersed with intermittent stopover periods for re-fuelling. However, little is known about the stopover ecology of songbirds migrating along the East Asian flyway. The aim of this study was to estimate the minimum stopover duration and body mass change during stopover of Red-flanked Bluetail Tarsiger cyanurus and Yellow-browed Warbler Phylloscopus inornatus based on 6,073 ringed and 502 re-captured birds during spring and autumn migration in the Russian Far East. For Red-flanked Bluetail the minimum stopover duration averaged 3.4 days in autumn and 1.7 days in spring, while for Yellow-browed Warbler it was 3.2 days in autumn and 2.1 days in spring. Significant differences in stopover duration were found between seasons, but not between the two species. The body mass of Red-flanked Bluetails significantly increased during stopover in spring and autumn, but no significant body mass changes were detected in Yellow-browed Warblers. The shorter minimum stopover duration of both species in spring may indicate a faster migration than in autumn, suggesting a time-minimizing strategy in spring to reach the breeding grounds as fast as possible.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"19 1","pages":"159 - 166"},"PeriodicalIF":0.6,"publicationDate":"2020-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47296739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The Eurasian Skylark, Alauda arvensis, is a passerine bird that mainly breeds in open habitats, such as lowland grasslands and farmlands. However, recent studies have shown that they form breeding territories on volcanic and alpine slopes in central/northern Japan. During the 2018 breeding season, we investigated the density and habitat selection of Skylarks on the volcanic slopes above timber line, of Mt. Tarumae, Hokkaido. Our results showed that there were 27 Skylark territories in the study area, with a density of 7.26 territories per square kilometer. This spatial arrangement was dense around the eastern slope. Skylarks favored habitats with a low vegetation height. The quantity of short plant species, i.e. Carex oxyandra and Arcterica nana was larger in territories than in randomly selected points. C. oxyandra plays important roles not only in forming low vegetation, but also in available and limited nest material in their breeding territories on the volcanic slopes. These results suggest that Skylarks occupy areas of low vegetation with C. oxyandra, as there are limited resources available for nest materials within the breeding territories that are on the volcanic slope above a timber line.
{"title":"Habitat Selection of Skylarks During the Breeding Season on the Volcanic Slope of Mt. Tarumae","authors":"Yôhei Itô, Shin Matsui, S. Shiraki, K. Ueda","doi":"10.2326/osj.19.167","DOIUrl":"https://doi.org/10.2326/osj.19.167","url":null,"abstract":"Abstract The Eurasian Skylark, Alauda arvensis, is a passerine bird that mainly breeds in open habitats, such as lowland grasslands and farmlands. However, recent studies have shown that they form breeding territories on volcanic and alpine slopes in central/northern Japan. During the 2018 breeding season, we investigated the density and habitat selection of Skylarks on the volcanic slopes above timber line, of Mt. Tarumae, Hokkaido. Our results showed that there were 27 Skylark territories in the study area, with a density of 7.26 territories per square kilometer. This spatial arrangement was dense around the eastern slope. Skylarks favored habitats with a low vegetation height. The quantity of short plant species, i.e. Carex oxyandra and Arcterica nana was larger in territories than in randomly selected points. C. oxyandra plays important roles not only in forming low vegetation, but also in available and limited nest material in their breeding territories on the volcanic slopes. These results suggest that Skylarks occupy areas of low vegetation with C. oxyandra, as there are limited resources available for nest materials within the breeding territories that are on the volcanic slope above a timber line.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"19 1","pages":"167 - 175"},"PeriodicalIF":0.6,"publicationDate":"2020-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43460062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Sawa, Chieko Tamura, Toshio Ikeuchi, T. Shimada, Kaoru Fujii, Aisa Ishioroshi, S. Tatsuzawa, D. Ward
Abstract The Brent Goose Branta bernicla population of East Asia is the least studied. We banded 24 Brent Geese at Notsuke Bay, east Hokkaido, Japan, in autumn, and collected six opportunistic sightings of these birds during winter, contributing to an understanding of their migratory movements to wintering sites in Japan. Birds were resighted at five widely distributed wintering sites in west Hokkaido and northeast Honshu. While this study showed that birds moved between Notsuke Bay and wintering sites elsewhere in Japan, further studies are needed to understand the migration patterns and routes used during autumn and spring in East Asia.
{"title":"Evidence of Brent Geese Branta bernicla Moving between an Autumn Staging Area in East Hokkaido and Wintering Sites in West Hokkaido and Northern Honshu","authors":"Y. Sawa, Chieko Tamura, Toshio Ikeuchi, T. Shimada, Kaoru Fujii, Aisa Ishioroshi, S. Tatsuzawa, D. Ward","doi":"10.2326/osj.19.211","DOIUrl":"https://doi.org/10.2326/osj.19.211","url":null,"abstract":"Abstract The Brent Goose Branta bernicla population of East Asia is the least studied. We banded 24 Brent Geese at Notsuke Bay, east Hokkaido, Japan, in autumn, and collected six opportunistic sightings of these birds during winter, contributing to an understanding of their migratory movements to wintering sites in Japan. Birds were resighted at five widely distributed wintering sites in west Hokkaido and northeast Honshu. While this study showed that birds moved between Notsuke Bay and wintering sites elsewhere in Japan, further studies are needed to understand the migration patterns and routes used during autumn and spring in East Asia.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"19 1","pages":"211 - 216"},"PeriodicalIF":0.6,"publicationDate":"2020-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45585502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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