Abstract The Asian Koel Eudynamys scolopaceus is an obligate brood parasite commonly known to parasitize open nests of various passerines. However, in the Philippines, no information on the Asian Koel's hosts is available. We present the first record of an Asian Koel parasitizing the cavity nest of a Coleto Sarcops calvus, at the Subic Watershed Forest Reserve, Luzon, Philippines. Our findings provide important insights into the species' brood parasitism in the Philippines and within its range.
{"title":"Brood Parasitism of the Asian Koel Eudynamys scolopaceus on the Tree Cavity-Nesting Coleto Sarcops calvus: First Record in the Philippines","authors":"Vince Angelo G. Gicaraya, C. Española","doi":"10.2326/osj.22.175","DOIUrl":"https://doi.org/10.2326/osj.22.175","url":null,"abstract":"Abstract The Asian Koel Eudynamys scolopaceus is an obligate brood parasite commonly known to parasitize open nests of various passerines. However, in the Philippines, no information on the Asian Koel's hosts is available. We present the first record of an Asian Koel parasitizing the cavity nest of a Coleto Sarcops calvus, at the Subic Watershed Forest Reserve, Luzon, Philippines. Our findings provide important insights into the species' brood parasitism in the Philippines and within its range.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"175 - 178"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49539638","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}
Savvas Iezekiel, K. Dimitriou, D. Bakaloudis, Evangelos G. Kotsonas, Marios Aristophanous, R. Yosef
Abstract In this paper we describe first breeding of Grey Wagtail Motacilla cinerea in Cyprus. Twenty-three nests were found during the 2020 and 2021 breeding seasons in riparian habitats adjacent to major river systems in the Paphos State Forest. Most nests were located on roadside banks at a height of 2.38 m above the ground and at a distance of about 0–10 m from the river. Nests consisted of grassy cups with a mean diameter of 13.39 cm, while the nest cup itself had a mean diameter of 7.07 cm and a depth of 3.41 cm. Twelve nesting attempts were monitored with females laying eggs between early April and early July. A total of 54 eggs were laid and 44 nestlings were successfully raised from the 12 nests. The mean clutch size was 4.5 eggs per nest, the mean number of hatched eggs was 3.92 and the mean number of fledglings was 3.67. Parents fed their young mostly on invertebrates and in particular on insects. Diptera and Odonata were the most common insect Orders comprising the majority of prey items. Average insect prey size was 10.79 mm (range 2–60 mm), with little difference in prey size between that delivered by males and females. This study confirms the first breeding of the species in Cyprus, where it follows a breeding pattern similar to that in other parts of Western Palearctic range. The affinity of the Grey Wagtail to human structures and the low predation rate highlight the successful breeding potential and the future range expansion of the species across the island of Cyprus.
{"title":"First Confirmed Breeding Records of Grey Wagtail Motacilla cinerea Tunstall, 1771 (Passeriformes: Motacillidae) in Cyprus","authors":"Savvas Iezekiel, K. Dimitriou, D. Bakaloudis, Evangelos G. Kotsonas, Marios Aristophanous, R. Yosef","doi":"10.2326/osj.22.151","DOIUrl":"https://doi.org/10.2326/osj.22.151","url":null,"abstract":"Abstract In this paper we describe first breeding of Grey Wagtail Motacilla cinerea in Cyprus. Twenty-three nests were found during the 2020 and 2021 breeding seasons in riparian habitats adjacent to major river systems in the Paphos State Forest. Most nests were located on roadside banks at a height of 2.38 m above the ground and at a distance of about 0–10 m from the river. Nests consisted of grassy cups with a mean diameter of 13.39 cm, while the nest cup itself had a mean diameter of 7.07 cm and a depth of 3.41 cm. Twelve nesting attempts were monitored with females laying eggs between early April and early July. A total of 54 eggs were laid and 44 nestlings were successfully raised from the 12 nests. The mean clutch size was 4.5 eggs per nest, the mean number of hatched eggs was 3.92 and the mean number of fledglings was 3.67. Parents fed their young mostly on invertebrates and in particular on insects. Diptera and Odonata were the most common insect Orders comprising the majority of prey items. Average insect prey size was 10.79 mm (range 2–60 mm), with little difference in prey size between that delivered by males and females. This study confirms the first breeding of the species in Cyprus, where it follows a breeding pattern similar to that in other parts of Western Palearctic range. The affinity of the Grey Wagtail to human structures and the low predation rate highlight the successful breeding potential and the future range expansion of the species across the island of Cyprus.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"151 - 159"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45707048","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 studied the diet of the Great Cormorant Phalacrocorax carbo, during the release period of juvenile Chum Salmon Oncorhynchus keta, at two sites in southeastern Aomori Prefecture. To understand the prey and size of the cormorants, we analyzed stomach contents in early spring 2016, and to determine whether cormorants prey on juvenile salmon or not, we conducted DNA metabarcoding of cormorant feces in winter 2017/2018. Although stomach content analysis indicated that juvenile salmon were a suitable size for the cormorants, very little Salmonidae DNA was detected from fecal samples. We found that there was food differentiation between the two study sites, and that the diet of cormorants was reflected in their roosting locations. Some fishes such Grey Mullet Mugil cephalus, Japanese Sardine Sardinops melanostictus and Cyprindae species were found to be primary prey of the cormorants during the study period.
{"title":"Dietary Analysis of the Great Cormorant Phalacrocorax carbo Wintering in Aomori Prefecture, Using DNA Metabarcoding","authors":"Kazunori Shizuka, S. Kasahara, N. Azuma","doi":"10.2326/osj.22.183","DOIUrl":"https://doi.org/10.2326/osj.22.183","url":null,"abstract":"Abstract We studied the diet of the Great Cormorant Phalacrocorax carbo, during the release period of juvenile Chum Salmon Oncorhynchus keta, at two sites in southeastern Aomori Prefecture. To understand the prey and size of the cormorants, we analyzed stomach contents in early spring 2016, and to determine whether cormorants prey on juvenile salmon or not, we conducted DNA metabarcoding of cormorant feces in winter 2017/2018. Although stomach content analysis indicated that juvenile salmon were a suitable size for the cormorants, very little Salmonidae DNA was detected from fecal samples. We found that there was food differentiation between the two study sites, and that the diet of cormorants was reflected in their roosting locations. Some fishes such Grey Mullet Mugil cephalus, Japanese Sardine Sardinops melanostictus and Cyprindae species were found to be primary prey of the cormorants during the study period.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"183 - 190"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46433098","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 Ryukyu Robin species complex, including the Ryukyu Robin Larvivora komadori and the Okinawa Robin L. namiyei, is endemic to the islands of the Ryukyu Archipelago. Population genetic structure and gene flow within this complex were investigated using 14 nuclear microsatellite markers. Distinct genetic differentiation was detected between the Ryukyu and Okinawa robins, and the Ryukyu Robin was further differentiated into four regional groups belonging to the Danjo Islands, Tokara Islands, Oh-shima with some adjacent islands, and Tokuno-shima. Contemporary gene flow among these regional groups was restricted overall, but outflow from the Tokara Islands group to the other three groups was exceptionally high. This asymmetric pattern may have been affected by differences in the isolation distance, migratory habits, and population size. The Ryukyu Robin species complex was long considered a single polytypic species; however, it has recently been classified as two independent species, mainly owing to the deep mitochondrial DNA divergence between them and a phenotypical re-examination. The genetic structure inferred from the nuclear loci strongly supports their genetic independence. The Okinawa Robin provides the first case among birds for which the splitting of sister species both endemic to the Ryukyu Archipelago is supported by all of the morphological, behavioral, ecological, and genetic evidence. Such recognition appears preferable in avian conservation and biogeography studies. Currently, the Ryukyu Archipelago includes an Endemic Bird Area and two Natural World Heritage sites, making the reliable delimitation of endemic species all the more important. Comprehensive genetic investigation, together with phenotypical re-examination is necessary, even for closely resembling but allopatric sister forms in this region.
摘要:琉球罗宾(Ryukyu Robin Larvivora komadori)和冲绳罗宾(Okinawa Robin L. namyei)是琉球群岛特有的物种群。利用14个核微卫星标记对该复合体的群体遗传结构和基因流进行了研究。琉球知更鸟与冲绳知更鸟之间存在明显的遗传分化，进一步将琉球知更鸟划分为四个区域类群，分别属于丹祖群岛、托卡拉群岛、大岛及其邻近岛屿和德野岛。这些区域群体之间的当代基因流动总体上受到限制，但从托卡拉群岛群体向其他三个群体的流出量异常高。这种不对称模式可能受到隔离距离、迁徙习惯和种群规模差异的影响。琉球知更鸟物种群长期以来被认为是单一的多型物种;然而，它最近被分类为两个独立的物种，主要是由于它们之间线粒体DNA的深度差异和表型的重新检查。从核位点推断的遗传结构有力地支持了它们的遗传独立性。在鸟类中，冲绳知更鸟提供了第一个案例，即琉球群岛特有的姐妹物种的分裂得到了所有形态学、行为学、生态学和遗传学证据的支持。这种认识在鸟类保护和生物地理学研究中更为可取。目前，琉球群岛包括一个特有鸟类区和两个世界自然遗产，这使得对特有物种的可靠划分变得更加重要。全面的遗传调查，连同表型重新检查是必要的，即使是在该地区非常相似但异源的姐妹形式。
{"title":"Fine-Scale Nuclear Genetic Structuring within the Ryukyu Robin, a Species Complex Endemic to the Ryukyu Archipelago","authors":"Shin‐Ichi Seki","doi":"10.2326/osj.22.137","DOIUrl":"https://doi.org/10.2326/osj.22.137","url":null,"abstract":"Abstract The Ryukyu Robin species complex, including the Ryukyu Robin Larvivora komadori and the Okinawa Robin L. namiyei, is endemic to the islands of the Ryukyu Archipelago. Population genetic structure and gene flow within this complex were investigated using 14 nuclear microsatellite markers. Distinct genetic differentiation was detected between the Ryukyu and Okinawa robins, and the Ryukyu Robin was further differentiated into four regional groups belonging to the Danjo Islands, Tokara Islands, Oh-shima with some adjacent islands, and Tokuno-shima. Contemporary gene flow among these regional groups was restricted overall, but outflow from the Tokara Islands group to the other three groups was exceptionally high. This asymmetric pattern may have been affected by differences in the isolation distance, migratory habits, and population size. The Ryukyu Robin species complex was long considered a single polytypic species; however, it has recently been classified as two independent species, mainly owing to the deep mitochondrial DNA divergence between them and a phenotypical re-examination. The genetic structure inferred from the nuclear loci strongly supports their genetic independence. The Okinawa Robin provides the first case among birds for which the splitting of sister species both endemic to the Ryukyu Archipelago is supported by all of the morphological, behavioral, ecological, and genetic evidence. Such recognition appears preferable in avian conservation and biogeography studies. Currently, the Ryukyu Archipelago includes an Endemic Bird Area and two Natural World Heritage sites, making the reliable delimitation of endemic species all the more important. Comprehensive genetic investigation, together with phenotypical re-examination is necessary, even for closely resembling but allopatric sister forms in this region.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"137 - 150"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44979822","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}
A. Sawada, Kiyohisa Tatematsu, Toshiyuki Kawano, M. Takagi
Abstract This report documents the first direct evidence of inter-island dispersal of Ryukyu Scops Owl Otus elegans. Out of 134 individuals marked on Hateruma-jima Island in 2021, a female, which had been first captured as an adult bird, was discovered alive on Ishigaki-jima Island in 2022. The distance between the points of capture and resighting was 52.7 km. Since owls in the genus Otus show diversification between islands, direct evidence of movement between islands as given here, can contribute to future studies on the evolutionary process of the Otus owls.
{"title":"First Direct Evidence of Inter-Island Dispersal of Ryukyu Scops Owl Otus elegans","authors":"A. Sawada, Kiyohisa Tatematsu, Toshiyuki Kawano, M. Takagi","doi":"10.2326/osj.22.191","DOIUrl":"https://doi.org/10.2326/osj.22.191","url":null,"abstract":"Abstract This report documents the first direct evidence of inter-island dispersal of Ryukyu Scops Owl Otus elegans. Out of 134 individuals marked on Hateruma-jima Island in 2021, a female, which had been first captured as an adult bird, was discovered alive on Ishigaki-jima Island in 2022. The distance between the points of capture and resighting was 52.7 km. Since owls in the genus Otus show diversification between islands, direct evidence of movement between islands as given here, can contribute to future studies on the evolutionary process of the Otus owls.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"191 - 194"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43965943","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 Neither the breeding status nor the fundamental ecology of Malayan Night Heron Gorsachius melanolophus is well-known. This report provides the first evidence of it breeding on Hateruma Island in Japan, where it has previously only been known from its calls. In 2022, a nest was found from which a fledgling was raised; the brooding period took more than 29 days. Although the species is commonly referred to as crepuscular or nocturnal, feeding events were recorded from the morning to the early evening.
{"title":"A Breeding Record of Malayan Night Heron Gorsachius melanolophus on Hateruma Island","authors":"A. Sawada","doi":"10.2326/osj.22.169","DOIUrl":"https://doi.org/10.2326/osj.22.169","url":null,"abstract":"Abstract Neither the breeding status nor the fundamental ecology of Malayan Night Heron Gorsachius melanolophus is well-known. This report provides the first evidence of it breeding on Hateruma Island in Japan, where it has previously only been known from its calls. In 2022, a nest was found from which a fledgling was raised; the brooding period took more than 29 days. Although the species is commonly referred to as crepuscular or nocturnal, feeding events were recorded from the morning to the early evening.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"169 - 174"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45050755","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}
M. Sakao, T. Hamabata, Katsufumi Sato, Shinichi Watanabe, K. Yoda, Kozue Shiomi
Abstract The genetic structure of Streaked Shearwater Calonectris leucomelas, a seabird breeding on islands around Japan, was investigated using nuclear microsatellite markers at four breeding colonies located in three geographically distinct areas (Pacific Ocean, Sea of Japan, and Seto Inland Sea). To investigate independently natal and breeding dispersal patterns, we analyzed records of recoveries of birds banded around Japan over a 30-year period from 1971 to 2020. The genetic marker analysis showed little differentiation among the breeding sites and a lack of population structure. In contrast, banding data presented few examples of natal and breeding dispersal and a much greater number of natal/breeding philopatry cases. Although further research is needed to understand the discrepancy between the genetic properties and recapture patterns of banded birds, some possible reasons are suggested: actual dispersal events may not have been fully detected by the banding research, thus, underestimating dispersal frequency; rare dispersal events may have functioned to reduce the genetic structure; and/or breeding colonies of this species might have been established recently, thus genetic markers may not be indicative of current dispersal patterns. In conclusion, our results indicate ongoing gene flow and/or strong historical association in this species.
{"title":"Absence of Genetic Structure among Streaked Shearwaters Calonectris leucomelas Breeding in Japan, Despite Limited Dispersal Events","authors":"M. Sakao, T. Hamabata, Katsufumi Sato, Shinichi Watanabe, K. Yoda, Kozue Shiomi","doi":"10.2326/osj.22.111","DOIUrl":"https://doi.org/10.2326/osj.22.111","url":null,"abstract":"Abstract The genetic structure of Streaked Shearwater Calonectris leucomelas, a seabird breeding on islands around Japan, was investigated using nuclear microsatellite markers at four breeding colonies located in three geographically distinct areas (Pacific Ocean, Sea of Japan, and Seto Inland Sea). To investigate independently natal and breeding dispersal patterns, we analyzed records of recoveries of birds banded around Japan over a 30-year period from 1971 to 2020. The genetic marker analysis showed little differentiation among the breeding sites and a lack of population structure. In contrast, banding data presented few examples of natal and breeding dispersal and a much greater number of natal/breeding philopatry cases. Although further research is needed to understand the discrepancy between the genetic properties and recapture patterns of banded birds, some possible reasons are suggested: actual dispersal events may not have been fully detected by the banding research, thus, underestimating dispersal frequency; rare dispersal events may have functioned to reduce the genetic structure; and/or breeding colonies of this species might have been established recently, thus genetic markers may not be indicative of current dispersal patterns. In conclusion, our results indicate ongoing gene flow and/or strong historical association in this species.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"111 - 121"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45814286","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}
Xiaogang Yao, Yan Cai, Ping Ye, W. Liang, Canchao Yang
Abstract Human activities exert a variety of impacts on birds; some are negatively influenced by these activities, while others benefit from them. Here we studied the relationship between the nest site selection of two sympatric cavity-nesting birds, Daurian Redstart Phoenicurus auroreus and Verditer Flycatcher Eumyias thalassinus and human houses, over thirteen years. The redstarts selected houses in which to nest because of the presence of people, whereas flycatchers chose to build nests in houses because of the houses themselves. It is thought that redstarts prefer to build nests in human structures because the presence of people reduces the risk of nest predation. In contrast, although breeding sympatrically, flycatchers built nests in houses where people were absent, indicating that it was not as sensitive as the redstart to human presence. Instead, they seem to prefer to nest in human residences because they provide suitable nesting sites. This study indicates that different species may adapt to human activities in different ways, even though they have similar habits and co-exist in the same habitat.
{"title":"Nesting Preferences of Two Cavity-Nesting Passerines in Human Houses","authors":"Xiaogang Yao, Yan Cai, Ping Ye, W. Liang, Canchao Yang","doi":"10.2326/osj.22.179","DOIUrl":"https://doi.org/10.2326/osj.22.179","url":null,"abstract":"Abstract Human activities exert a variety of impacts on birds; some are negatively influenced by these activities, while others benefit from them. Here we studied the relationship between the nest site selection of two sympatric cavity-nesting birds, Daurian Redstart Phoenicurus auroreus and Verditer Flycatcher Eumyias thalassinus and human houses, over thirteen years. The redstarts selected houses in which to nest because of the presence of people, whereas flycatchers chose to build nests in houses because of the houses themselves. It is thought that redstarts prefer to build nests in human structures because the presence of people reduces the risk of nest predation. In contrast, although breeding sympatrically, flycatchers built nests in houses where people were absent, indicating that it was not as sensitive as the redstart to human presence. Instead, they seem to prefer to nest in human residences because they provide suitable nesting sites. This study indicates that different species may adapt to human activities in different ways, even though they have similar habits and co-exist in the same habitat.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"179 - 182"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45853197","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}
D. Higashide, Takeo Kuriyama, S. Takagi, Hiroo Numata, M. Yokoyama
Abstract Japanese Night Heron Gorsachius goisagi has recently been down-listed in status from Endangered to Vulnerable by BirdLife International due to the presence of a likely larger population than previously considered. However, there is still relatively little known about the ecology and current population status of this rare, elusive, and solitary species. In this study, we used infrared cameras to study its behaviour. We installed cameras at 120 locations on the forest floor of Awaji Island, Hyogo Prefecture, Japan, over approximately one year. Japanese Night Heron was recorded at 15 locations (132 video files of 25 independent events). All records except one were obtained during the daytime, and all involved herons walking on the forest floor where they were searching for potential prey items (most likely earthworms). Both adult and recently fledged juvenile herons were recorded, providing direct evidence that the species breeds on Awaji Island. Additionally, a zero-inflated Poisson GLMM analysis showed that Japanese Night Heron may not prefer evergreen coniferous plantations. Our results not only indicate that the species forages diurnally, contrary to its common name, but also sheds light on the importance of maintaining forests and foraging ground environments for the conservation of this species.
{"title":"The Behaviour of Japanese Night Heron Gorsachius goisagi on Awaji Island, Japan, Recorded by Camera Traps","authors":"D. Higashide, Takeo Kuriyama, S. Takagi, Hiroo Numata, M. Yokoyama","doi":"10.2326/osj.22.161","DOIUrl":"https://doi.org/10.2326/osj.22.161","url":null,"abstract":"Abstract Japanese Night Heron Gorsachius goisagi has recently been down-listed in status from Endangered to Vulnerable by BirdLife International due to the presence of a likely larger population than previously considered. However, there is still relatively little known about the ecology and current population status of this rare, elusive, and solitary species. In this study, we used infrared cameras to study its behaviour. We installed cameras at 120 locations on the forest floor of Awaji Island, Hyogo Prefecture, Japan, over approximately one year. Japanese Night Heron was recorded at 15 locations (132 video files of 25 independent events). All records except one were obtained during the daytime, and all involved herons walking on the forest floor where they were searching for potential prey items (most likely earthworms). Both adult and recently fledged juvenile herons were recorded, providing direct evidence that the species breeds on Awaji Island. Additionally, a zero-inflated Poisson GLMM analysis showed that Japanese Night Heron may not prefer evergreen coniferous plantations. Our results not only indicate that the species forages diurnally, contrary to its common name, but also sheds light on the importance of maintaining forests and foraging ground environments for the conservation of this species.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"161 - 168"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41572912","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 Since human settlement of the Ogasawara Islands in the early 19th century, several bird species have become extinct owing to the impact of the introduction of non-native species, and other factors. In particular, on the island of Hahajima, seabird breeding colonies have been devastated. This study aimed to determine the relationship between the endemic subspecies of Eastern Buzzard Buteo japonicus toyoshimai and various non-native rats on Hahajima, Ogasawara Islands, Japan. Over a period of 5–10 years video-recordings were made of food being delivered to buzzard nests at three study sites on Hahajima. Rats Rattus spp. were the most abundant prey delivered to the nestlings, accounting for 71–91% of prey items and 83–96% of prey weight; next in abundance was the introduced Green Anole Anolis carolinensis, 6–21% in number. However, since anoles are much smaller than rats, even at the study site where a high proportion of anoles were delivered, the buzzard pair there did not consume fewer rats than at the other sites. Only a small number of birds (1–6%) were delivered to the nests. At one site, where breeding occurred seven times during the study period, there was a significant positive correlation between the number of rats delivered to the nest during the nestling period and precipitation in the October before breeding and in January of the year of breeding.
{"title":"Eastern Buzzard Buteo japonicus toyoshimai Breeding on the Ogasawara Islands Depend on Non-Native Rats as a Food Source","authors":"Masahiro Hayama, Masatoshi Yui","doi":"10.2326/osj.22.123","DOIUrl":"https://doi.org/10.2326/osj.22.123","url":null,"abstract":"Abstract Since human settlement of the Ogasawara Islands in the early 19th century, several bird species have become extinct owing to the impact of the introduction of non-native species, and other factors. In particular, on the island of Hahajima, seabird breeding colonies have been devastated. This study aimed to determine the relationship between the endemic subspecies of Eastern Buzzard Buteo japonicus toyoshimai and various non-native rats on Hahajima, Ogasawara Islands, Japan. Over a period of 5–10 years video-recordings were made of food being delivered to buzzard nests at three study sites on Hahajima. Rats Rattus spp. were the most abundant prey delivered to the nestlings, accounting for 71–91% of prey items and 83–96% of prey weight; next in abundance was the introduced Green Anole Anolis carolinensis, 6–21% in number. However, since anoles are much smaller than rats, even at the study site where a high proportion of anoles were delivered, the buzzard pair there did not consume fewer rats than at the other sites. Only a small number of birds (1–6%) were delivered to the nests. At one site, where breeding occurred seven times during the study period, there was a significant positive correlation between the number of rats delivered to the nest during the nestling period and precipitation in the October before breeding and in January of the year of breeding.","PeriodicalId":49009,"journal":{"name":"Ornithological Science","volume":"22 1","pages":"123 - 135"},"PeriodicalIF":0.6,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49588998","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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