Yuta Inoue, Yutaro Suzuki, Kaori Hanazaki, Hitoshi Suzuki
Abstract. Quaternary environmental change provided opportunities for rapid population expansion; however, the process of building the population spatial structures remains poorly understood. In this study, we determined the mitochondrial cytochrome b and control region sequences of 43 individuals of the large Japanese wood mouse (Apodemus speciosus) from Hokkaido, northern Japan and analyzed these data along with those from 40 other individuals. Consistent with the findings of our previous study, we found that two rapid expansion events, after the last glacial maximum (LGM) and Marine Isotope Stage (MIS) 4, shaped population genetic pattern of A. speciosus in Hokkaido. In northeastern Hokkaido, several ancient lineages that originated during MIS 3 were detected, whereas central Hokkaido was dominated by haplotypes descended from a single lineage that survived the LGM, suggesting that the populations of western part of Hokkaido were newly formed by westward migration from eastern Hokkaido during the post-LGM warm period. Alternatively, as post-LGM vegetation recovery is thought to have occurred gradually from west to east in Hokkaido, population expansion started in the west and moved gradually to the east, resulting in eastward haplotype movement; thus, western and eastern Hokkaido may have served as the haplotype source and sink, respectively.
{"title":"Quaternary Environmental Changes Shaped Mitochondrial DNA Diversity in the Large Japanese Wood Mouse Apodemus speciosus in Hokkaido, Japan","authors":"Yuta Inoue, Yutaro Suzuki, Kaori Hanazaki, Hitoshi Suzuki","doi":"10.3106/ms2021-0050","DOIUrl":"https://doi.org/10.3106/ms2021-0050","url":null,"abstract":"Abstract. Quaternary environmental change provided opportunities for rapid population expansion; however, the process of building the population spatial structures remains poorly understood. In this study, we determined the mitochondrial cytochrome b and control region sequences of 43 individuals of the large Japanese wood mouse (Apodemus speciosus) from Hokkaido, northern Japan and analyzed these data along with those from 40 other individuals. Consistent with the findings of our previous study, we found that two rapid expansion events, after the last glacial maximum (LGM) and Marine Isotope Stage (MIS) 4, shaped population genetic pattern of A. speciosus in Hokkaido. In northeastern Hokkaido, several ancient lineages that originated during MIS 3 were detected, whereas central Hokkaido was dominated by haplotypes descended from a single lineage that survived the LGM, suggesting that the populations of western part of Hokkaido were newly formed by westward migration from eastern Hokkaido during the post-LGM warm period. Alternatively, as post-LGM vegetation recovery is thought to have occurred gradually from west to east in Hokkaido, population expansion started in the west and moved gradually to the east, resulting in eastward haplotype movement; thus, western and eastern Hokkaido may have served as the haplotype source and sink, respectively.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"249 - 259"},"PeriodicalIF":1.0,"publicationDate":"2022-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43879649","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. It is known that the development of roadway systems can benefit bats, particularly cave- and crevice-roosting species, by providing novel roosting resources, e.g., abandoned tunnels and underpasses. However, the usage of operational road tunnels by bats, and its pros and cons are often overlooked. In the present study, we investigated bat diversity in 18 road tunnels in a subtropical forested mountain in Taiwan from 2018 to 2019. A total of 139 insectivorous bat sightings were recorded from 13 tunnels and 76.3% of the samples were identified to 12 species. Surprisingly, 75% of the species were previously regarded as non-cave specialists. Bat occurrences show spatial, temporal, and taxonomic aggregations as around 90% of the observations were contributed by four morpho-species from five tunnels in the summer and fall seasons. The among-site variations in species composition can be explained by tunnel morphology and presence of operational streetlight by the entrances. Since roadkill and grounded individuals, particularly juvenile Pipistrellus, were often found during surveys, these tunnels may act as ecological traps rather than suitable roosts to bats. Future confirmation of the roles of these tunnels to bats is necessary by measuring fitness through behavioral observations and long-term monitoring.
{"title":"Roost Use of Operational Road Tunnels by Non-Cave Specialist Bats in a Subtropical Mountain Forest in Taiwan","authors":"Joe Chun‐Chia Huang, Ya-Wen Yang, Heng-Chia Chang","doi":"10.3106/ms2020-0087","DOIUrl":"https://doi.org/10.3106/ms2020-0087","url":null,"abstract":"Abstract. It is known that the development of roadway systems can benefit bats, particularly cave- and crevice-roosting species, by providing novel roosting resources, e.g., abandoned tunnels and underpasses. However, the usage of operational road tunnels by bats, and its pros and cons are often overlooked. In the present study, we investigated bat diversity in 18 road tunnels in a subtropical forested mountain in Taiwan from 2018 to 2019. A total of 139 insectivorous bat sightings were recorded from 13 tunnels and 76.3% of the samples were identified to 12 species. Surprisingly, 75% of the species were previously regarded as non-cave specialists. Bat occurrences show spatial, temporal, and taxonomic aggregations as around 90% of the observations were contributed by four morpho-species from five tunnels in the summer and fall seasons. The among-site variations in species composition can be explained by tunnel morphology and presence of operational streetlight by the entrances. Since roadkill and grounded individuals, particularly juvenile Pipistrellus, were often found during surveys, these tunnels may act as ecological traps rather than suitable roosts to bats. Future confirmation of the roles of these tunnels to bats is necessary by measuring fitness through behavioral observations and long-term monitoring.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"213 - 224"},"PeriodicalIF":1.0,"publicationDate":"2022-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46444966","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. Kobayashi, Kishio Maeda, Hisao Tamura, M. Izawa
Abstract. A bat was rescued from Okinawajima Island, Ryukyu Archipelago, Japan in November 2021. Observing the external characteristics, we identified it as the black-bearded tomb bat, Taphozous melanopogon Temminck, 1841, which is mainly distributed in tropical Asia. To our knowledge, this is the first record of this species in Japan. However, we infer that it was accidentally only visiting and not established on Okinawajima Island.
{"title":"First Record of the Black-Bearded Tomb Bat Taphozous melanopogon Temminck, 1841 (Chiroptera: Emballonuridae) from Japan","authors":"S. Kobayashi, Kishio Maeda, Hisao Tamura, M. Izawa","doi":"10.3106/ms2022-0007","DOIUrl":"https://doi.org/10.3106/ms2022-0007","url":null,"abstract":"Abstract. A bat was rescued from Okinawajima Island, Ryukyu Archipelago, Japan in November 2021. Observing the external characteristics, we identified it as the black-bearded tomb bat, Taphozous melanopogon Temminck, 1841, which is mainly distributed in tropical Asia. To our knowledge, this is the first record of this species in Japan. However, we infer that it was accidentally only visiting and not established on Okinawajima Island.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"261 - 264"},"PeriodicalIF":1.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43809091","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 explored the genetic diversity and population genetic structure of an invasive alien species, the raccoon Procyon lotor, which was introduced into the Shikoku Island of Japan, using sequences of the mitochondrial control region and 10 polymorphic microsatellite loci. In 80 individuals examined, we detected two genetically divergent haplotypes, indicating that two maternal lineages had been introduced into Shikoku Island. Population clustering analysis suggested the nonexistence of genetic structure in the area. The relatedness network showed that the raccoon population in Shikoku Island consisted of closely related individuals. The genetic diversity of the Shikoku raccoon population was lower than that in the native range. These results and a prior report indicate that the Shikoku raccoon population is likely to have expanded from small numbers of founders originating from an initial invasive population. Raccoon captures outside Kagawa are decreasing, although past expansions into Tokushima and Ehime suggest that there are no geographical barriers among these areas. Therefore, action should be taken to prevent any re-expansion of the raccoon population in Kagawa. Intensive monitoring and the elimination of dispersers from Kagawa, as well as effort to eradicate potential source populations for expansion in Kagawa, are needed.
{"title":"The Genetic Diversity and Structure of the Feral Raccoon (Procyon lotor) Population in Shikoku Island, Japan","authors":"T. Yamashiro, Y. Kaneshiro, A. Yamashiro, M. Maki","doi":"10.3106/ms2021-0052","DOIUrl":"https://doi.org/10.3106/ms2021-0052","url":null,"abstract":"Abstract. We explored the genetic diversity and population genetic structure of an invasive alien species, the raccoon Procyon lotor, which was introduced into the Shikoku Island of Japan, using sequences of the mitochondrial control region and 10 polymorphic microsatellite loci. In 80 individuals examined, we detected two genetically divergent haplotypes, indicating that two maternal lineages had been introduced into Shikoku Island. Population clustering analysis suggested the nonexistence of genetic structure in the area. The relatedness network showed that the raccoon population in Shikoku Island consisted of closely related individuals. The genetic diversity of the Shikoku raccoon population was lower than that in the native range. These results and a prior report indicate that the Shikoku raccoon population is likely to have expanded from small numbers of founders originating from an initial invasive population. Raccoon captures outside Kagawa are decreasing, although past expansions into Tokushima and Ehime suggest that there are no geographical barriers among these areas. Therefore, action should be taken to prevent any re-expansion of the raccoon population in Kagawa. Intensive monitoring and the elimination of dispersers from Kagawa, as well as effort to eradicate potential source populations for expansion in Kagawa, are needed.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"189 - 196"},"PeriodicalIF":1.0,"publicationDate":"2022-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43052349","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}
Akira Kuroyanagi, Rina Ukyo, Yoshinobu Kodama, Takeshi Eto, Yoshinobu Okubo, I. Kobayashi, S. Ieiri, Tetsuo Morita, Shinsuke H. Sakamoto
Abstract. This study illustrated body temperature (Tb) fluctuation during reproduction and discussed the effectiveness of measuring Tb for predicting the reproductive profile of female Apodemus speciosus both under laboratory and field conditions. Tb fluctuation was monitored for four breeding events in the laboratory and for three in the field. Individual variation in Tb fluctuation during reproduction was larger in the field than in the laboratory, while its temporal pattern was clearer in the field than in the laboratory. Tb fluctuating patterns according to the progress of the reproductive stage were similar between the laboratory and the field. Daily mean Tb increased after the start of pregnancy, decreased during late pregnancy, rapidly increased after parturition, and remained higher through the lactation period. In particular, the following three characteristics should be apparent indices of parturition: increase of daily mean Tb and daily minimum Tb in early pregnancy, decrease of daily max Tb and daily mean Tb in late pregnancy, and increase of daily max Tb at the day of parturition. These results indicate that implanting small-sized loggers enables us to obtain a representative pattern of Tb fluctuation and to predict the reproductive profile of female A. speciosus, both under laboratory and field conditions.
{"title":"Body Temperature Measurement Reveals the Reproductive Profile of Female Apodemus speciosus under Laboratory and Field Conditions","authors":"Akira Kuroyanagi, Rina Ukyo, Yoshinobu Kodama, Takeshi Eto, Yoshinobu Okubo, I. Kobayashi, S. Ieiri, Tetsuo Morita, Shinsuke H. Sakamoto","doi":"10.3106/ms2021-0048","DOIUrl":"https://doi.org/10.3106/ms2021-0048","url":null,"abstract":"Abstract. This study illustrated body temperature (Tb) fluctuation during reproduction and discussed the effectiveness of measuring Tb for predicting the reproductive profile of female Apodemus speciosus both under laboratory and field conditions. Tb fluctuation was monitored for four breeding events in the laboratory and for three in the field. Individual variation in Tb fluctuation during reproduction was larger in the field than in the laboratory, while its temporal pattern was clearer in the field than in the laboratory. Tb fluctuating patterns according to the progress of the reproductive stage were similar between the laboratory and the field. Daily mean Tb increased after the start of pregnancy, decreased during late pregnancy, rapidly increased after parturition, and remained higher through the lactation period. In particular, the following three characteristics should be apparent indices of parturition: increase of daily mean Tb and daily minimum Tb in early pregnancy, decrease of daily max Tb and daily mean Tb in late pregnancy, and increase of daily max Tb at the day of parturition. These results indicate that implanting small-sized loggers enables us to obtain a representative pattern of Tb fluctuation and to predict the reproductive profile of female A. speciosus, both under laboratory and field conditions.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"177 - 187"},"PeriodicalIF":1.0,"publicationDate":"2022-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44224398","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. Comprehensive information on prey availability and diet composition is important to formulate effective conservation strategies. Data on these of large apex predators, the tiger Panthera tigris, leopard Panthera pardus, and dhole Cuon alpinus, are deficient in Kalakkad-Mundanthurai Tiger Reserve, India, which harbors low prey density. Therefore, we investigated how these predators coexisted by partitioning limited food resources. We found that prey selection and activity patterns differed among predators. The leopard (D [Jacobs' preference index] = +0.916) and dhole (D = +0.937) preferred the Indian chevrotain Moschiola indica, whereas the tiger preferred the gaur Bos gaurus (D = +0.937). Biomass of tiger's diet mainly consisted of the gaur (75%). In the dhole, the Indian chevrotain and sambar Rusa unicolor together contributed 91% of biomass, whereas 79% of leopard's biomass was contributed by the Nilgiri langur Semnopithecus johnii and the Indian chevrotain. The leopard and dhole had the highest dietary overlap (Ojk [Pianka Index] = 0.46). The highest activity overlap was found among the leopard, Indian chevrotain, and sambar. The leopard and dhole would compete for the Indian chevrotain, although the competition may be avoided by different activity patterns. Managements of the Indian chevrotain and gaur are critical for conserving large predators in the region.
{"title":"Diet Composition and Prey Preference of Tiger, Leopard, and Dhole in Kalakkad-Mundanthurai Tiger Reserve, Southern Western Ghats, India","authors":"B. Krishnakumar, R. Nagarajan, K. Selvan","doi":"10.3106/ms2020-0058","DOIUrl":"https://doi.org/10.3106/ms2020-0058","url":null,"abstract":"Abstract. Comprehensive information on prey availability and diet composition is important to formulate effective conservation strategies. Data on these of large apex predators, the tiger Panthera tigris, leopard Panthera pardus, and dhole Cuon alpinus, are deficient in Kalakkad-Mundanthurai Tiger Reserve, India, which harbors low prey density. Therefore, we investigated how these predators coexisted by partitioning limited food resources. We found that prey selection and activity patterns differed among predators. The leopard (D [Jacobs' preference index] = +0.916) and dhole (D = +0.937) preferred the Indian chevrotain Moschiola indica, whereas the tiger preferred the gaur Bos gaurus (D = +0.937). Biomass of tiger's diet mainly consisted of the gaur (75%). In the dhole, the Indian chevrotain and sambar Rusa unicolor together contributed 91% of biomass, whereas 79% of leopard's biomass was contributed by the Nilgiri langur Semnopithecus johnii and the Indian chevrotain. The leopard and dhole had the highest dietary overlap (Ojk [Pianka Index] = 0.46). The highest activity overlap was found among the leopard, Indian chevrotain, and sambar. The leopard and dhole would compete for the Indian chevrotain, although the competition may be avoided by different activity patterns. Managements of the Indian chevrotain and gaur are critical for conserving large predators in the region.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"141 - 153"},"PeriodicalIF":1.0,"publicationDate":"2022-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48462013","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. Motokawa, Tomohisa Makino, Takashi O. Yato, S. Okabe, Tsunehiro Shiroma, M. Toyama, H. Ota
Abstract. Based on mitochondrial cytochrome b gene sequences, we report representatives of the Lineage IV of Rattus tanezumi (Rodentia: Muridae) from Miyakojima, Taramajima, and Yonagunijima Islands in the southern Ryukyus as the first record of the lineage from Japan. The new record of Lineage IV provides an addition to the mammal fauna of Japan essentially at the species level. Accordingly, the genus Rattus in Japan consists of five species: R. rattus, Lineage II of R. tanezumi, Lineage IV of R. tanezumi, R. norvegicus, and R. exulans. The Miyakojima–Taramajima and Yonagunijima samples of the Lineage IV had discernible genetic differences, suggesting different origins. From Miyakojima Island and Kojima Island (an islet close to Miyakojima Island). We also found Lineage II of R. tanezumi, indicating that the two lineages coexist on Miyakojima Island. Morphological comparisons of these Lineage IV and Lineage II specimens suggest a greater molar length in Lineage IV than in Lineage II, and differences in the foramen magnum shape. Future detailed studies on genetic structures, morphological characteristics, and distribution of Lineage IV and Lineage II rats in the southern Ryukyus are needed to clarify their evolutionary history.
{"title":"First Record of Lineage IV of Rattus tanezumi (Rodentia: Muridae) from the southern Ryukyus, Japan","authors":"M. Motokawa, Tomohisa Makino, Takashi O. Yato, S. Okabe, Tsunehiro Shiroma, M. Toyama, H. Ota","doi":"10.3106/ms2022-0001","DOIUrl":"https://doi.org/10.3106/ms2022-0001","url":null,"abstract":"Abstract. Based on mitochondrial cytochrome b gene sequences, we report representatives of the Lineage IV of Rattus tanezumi (Rodentia: Muridae) from Miyakojima, Taramajima, and Yonagunijima Islands in the southern Ryukyus as the first record of the lineage from Japan. The new record of Lineage IV provides an addition to the mammal fauna of Japan essentially at the species level. Accordingly, the genus Rattus in Japan consists of five species: R. rattus, Lineage II of R. tanezumi, Lineage IV of R. tanezumi, R. norvegicus, and R. exulans. The Miyakojima–Taramajima and Yonagunijima samples of the Lineage IV had discernible genetic differences, suggesting different origins. From Miyakojima Island and Kojima Island (an islet close to Miyakojima Island). We also found Lineage II of R. tanezumi, indicating that the two lineages coexist on Miyakojima Island. Morphological comparisons of these Lineage IV and Lineage II specimens suggest a greater molar length in Lineage IV than in Lineage II, and differences in the foramen magnum shape. Future detailed studies on genetic structures, morphological characteristics, and distribution of Lineage IV and Lineage II rats in the southern Ryukyus are needed to clarify their evolutionary history.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"205 - 212"},"PeriodicalIF":1.0,"publicationDate":"2022-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69272259","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}
J. Nagata, Atsushi Haga, Y. Kusachi, Mikuni Tokuyoshi, H. Endo, Y. Watari
Abstract. The domestic cat Felis silvestris catus is known to be one of the most notorious invasive alien predators. Seabirds are typical taxonomic groups that have been impacted by free-ranging cats on islands, and their headless carcasses are frequently observed. We conducted genetic predator identification of the carcasses of streaked shearwater Calonectris leucomelas and described their characteristics on Mikura Island, Japan, where free-ranging cats were blamed for the recent rapid decline of the shearwater population. Eight carcasses of streaked shearwaters were found in the survey. Genetic analysis of swab samples from scarred tissues of the carcasses detected cat DNA and identified cat predation on six out of eight carcasses. All six cat-positive carcasses were headless or almost headless with the head and body faintly connected by esophagus and trachea, several of which were missing their intestines. We describe the conditions of these headless carcasses, noting the main characteristics that could lead to suspicion of cat predation. To the best of our knowledge, this is the first genetic predator identification using seabirds, and may make more stakeholders aware of the reality of cat predation worldwide. On Mikura Island, we expect that this evidence will contribute to the development of systematic cat management. Abstract in Japanese （要旨）． オオミズナギドリの首なし死骸はネコの捕食によるものだった：遺伝学的捕 食者検出によるエビデンス．イエネコ Felis silvestris catus は，最も有名な侵略的外来捕食者の一つとして知 られている．海鳥は，島嶼においてイエネコの影響を受けてきた典型的な分類群であり，首のない死骸が頻 繁に観察されることがある．本研究では，御蔵島において，イエネコによって近年個体数が減少していると 言われているオオミズナギドリ Calonectris leucomelas の死骸を対象に，遺伝的捕食者検出を行い，さらに死 骸の特徴を明らかにした．今回の調査では，オオミズナギドリの死骸を 8 個体分発見した．死骸の傷口から 採取したスワブサンプルの遺伝子分析により，8 つの死骸のうち 6 つでイエネコの DNA が検出され，イエ ネコの捕食が確認された．これら 6 つの死骸はすべて頭がないか，頭がかろうじて食道や器官で胴体部とつ ながったほぼ首なしという状態で，そのうちのいくつかは消化管も消失していた．本研究では，この首なし という死骸の状態について，イエネコの捕食を疑うことができる主な特徴として提示する．我々の知る限り， 本研究は海鳥を対象とした初めての遺伝的捕食者検出の事例であり，これにより世界的なイエネコの捕食の 実態が，より多くの関係者に認識されるようになるであろう．さらに，この遺伝学的エビデンスが御蔵島に おける本格的なイエネコ対策の展開に貢献することも期待される
{"title":"Cats were Responsible for the Headless Carcasses of Shearwaters: Evidence from Genetic Predator Identification","authors":"J. Nagata, Atsushi Haga, Y. Kusachi, Mikuni Tokuyoshi, H. Endo, Y. Watari","doi":"10.3106/ms2021-0047","DOIUrl":"https://doi.org/10.3106/ms2021-0047","url":null,"abstract":"Abstract. The domestic cat Felis silvestris catus is known to be one of the most notorious invasive alien predators. Seabirds are typical taxonomic groups that have been impacted by free-ranging cats on islands, and their headless carcasses are frequently observed. We conducted genetic predator identification of the carcasses of streaked shearwater Calonectris leucomelas and described their characteristics on Mikura Island, Japan, where free-ranging cats were blamed for the recent rapid decline of the shearwater population. Eight carcasses of streaked shearwaters were found in the survey. Genetic analysis of swab samples from scarred tissues of the carcasses detected cat DNA and identified cat predation on six out of eight carcasses. All six cat-positive carcasses were headless or almost headless with the head and body faintly connected by esophagus and trachea, several of which were missing their intestines. We describe the conditions of these headless carcasses, noting the main characteristics that could lead to suspicion of cat predation. To the best of our knowledge, this is the first genetic predator identification using seabirds, and may make more stakeholders aware of the reality of cat predation worldwide. On Mikura Island, we expect that this evidence will contribute to the development of systematic cat management. Abstract in Japanese （要旨）． オオミズナギドリの首なし死骸はネコの捕食によるものだった：遺伝学的捕 食者検出によるエビデンス．イエネコ Felis silvestris catus は，最も有名な侵略的外来捕食者の一つとして知 られている．海鳥は，島嶼においてイエネコの影響を受けてきた典型的な分類群であり，首のない死骸が頻 繁に観察されることがある．本研究では，御蔵島において，イエネコによって近年個体数が減少していると 言われているオオミズナギドリ Calonectris leucomelas の死骸を対象に，遺伝的捕食者検出を行い，さらに死 骸の特徴を明らかにした．今回の調査では，オオミズナギドリの死骸を 8 個体分発見した．死骸の傷口から 採取したスワブサンプルの遺伝子分析により，8 つの死骸のうち 6 つでイエネコの DNA が検出され，イエ ネコの捕食が確認された．これら 6 つの死骸はすべて頭がないか，頭がかろうじて食道や器官で胴体部とつ ながったほぼ首なしという状態で，そのうちのいくつかは消化管も消失していた．本研究では，この首なし という死骸の状態について，イエネコの捕食を疑うことができる主な特徴として提示する．我々の知る限り， 本研究は海鳥を対象とした初めての遺伝的捕食者検出の事例であり，これにより世界的なイエネコの捕食の 実態が，より多くの関係者に認識されるようになるであろう．さらに，この遺伝学的エビデンスが御蔵島に おける本格的なイエネコ対策の展開に貢献することも期待される","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"197 - 204"},"PeriodicalIF":1.0,"publicationDate":"2022-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42399907","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. In response to severe vegetation degradation caused by sika deer in Japan, it is important to understand the habitat use trends of the sika deer and sympatric Japanese serows to promote the management and conservation of both species and their habitats. This study used camera traps to examine the trends of habitat use of the two sympatric ungulates in the Kuraiyama Experimental Forest (KEF) at Gifu University. We set camera traps at 20 sites and evaluated the number of individuals photographed for three years. Additionally, we surveyed several environmental factors around the camera trap sites to determine the relationship between species prevalence and habitat features. Both species were photographed at all sites, and some habitat use trends were observed. The deer used the west side of the valley, whereas the serows used the east, with clearer trends further observed in summer. Both ungulates avoided snow cover in winter and used steeper slopes and ridges in several seasons. With the current increase in the deer population, niche overlap between the two species may occur in the common place preferred by both species; therefore, careful monitoring of their relationships and their changes should be continued in the future.
{"title":"Trends in Habitat Use between Sympatric Sika Deer and Japanese Serow as Revealed by Camera Traps","authors":"Satsuki Nakamori, M. Ando","doi":"10.3106/ms2021-0012","DOIUrl":"https://doi.org/10.3106/ms2021-0012","url":null,"abstract":"Abstract. In response to severe vegetation degradation caused by sika deer in Japan, it is important to understand the habitat use trends of the sika deer and sympatric Japanese serows to promote the management and conservation of both species and their habitats. This study used camera traps to examine the trends of habitat use of the two sympatric ungulates in the Kuraiyama Experimental Forest (KEF) at Gifu University. We set camera traps at 20 sites and evaluated the number of individuals photographed for three years. Additionally, we surveyed several environmental factors around the camera trap sites to determine the relationship between species prevalence and habitat features. Both species were photographed at all sites, and some habitat use trends were observed. The deer used the west side of the valley, whereas the serows used the east, with clearer trends further observed in summer. Both ungulates avoided snow cover in winter and used steeper slopes and ridges in several seasons. With the current increase in the deer population, niche overlap between the two species may occur in the common place preferred by both species; therefore, careful monitoring of their relationships and their changes should be continued in the future.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"165 - 176"},"PeriodicalIF":1.0,"publicationDate":"2022-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46612141","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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