Aleksandr A. Kisleyko, V. Dinets, M. Grishchenko, Evgeny E. Kozlovskiy, L. Khlyap
Abstract. In the early 1980s, the European mink (Mustela lutreola) was introduced on Kunashir [Kunashiri] Island in the Kuril [Chishima] Islands in order to preserve it in a region where its main competitor, the American mink (Neovison vison), is absent. We present records of the European mink on Kunashir in 2014–2021. In 23 cases, mink footprints were recorded on the snow or on sandbanks; in other nine cases, the animals were recorded visually or using camera traps. Camera trap photos reliably confirm the existence of a European mink population far from its severely contracted native range. The data were used to compose the dataset “Database of the European mink [Mustela lutreola (Linnaeus, 1761)] occurrence on Kunashir Island” that was transferred to the open international repository GBIF.
{"title":"The European Mink (Mustela lutreola) on Kunashir Island: Confirmed Survival 40 years After Introduction","authors":"Aleksandr A. Kisleyko, V. Dinets, M. Grishchenko, Evgeny E. Kozlovskiy, L. Khlyap","doi":"10.3106/ms2021-0044","DOIUrl":"https://doi.org/10.3106/ms2021-0044","url":null,"abstract":"Abstract. In the early 1980s, the European mink (Mustela lutreola) was introduced on Kunashir [Kunashiri] Island in the Kuril [Chishima] Islands in order to preserve it in a region where its main competitor, the American mink (Neovison vison), is absent. We present records of the European mink on Kunashir in 2014–2021. In 23 cases, mink footprints were recorded on the snow or on sandbanks; in other nine cases, the animals were recorded visually or using camera traps. Camera trap photos reliably confirm the existence of a European mink population far from its severely contracted native range. The data were used to compose the dataset “Database of the European mink [Mustela lutreola (Linnaeus, 1761)] occurrence on Kunashir Island” that was transferred to the open international repository GBIF.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"155 - 164"},"PeriodicalIF":1.0,"publicationDate":"2022-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42456901","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 the Japanese field mice, Apodemus argenteus and A. speciosus, loss of a tail part has often been observed under natural conditions. Such loss is considered a way of avoiding damage during physical accidents and attacks. Here, we studied the types of losses, types of caudal breakages, and breakage positions along the tail. The losses mainly consisted of intervertebral breakage (inter-VB) and intravertebral breakage (intra-VB). VB occurred widely along the tail in both Apodemus species and showed no specific tendency for the inter-VB positions. Intra-VB was confirmed at caudal vertebrae of the middle portion of the tail, consisting of vertebrae with lower relative width (minimum width/maximum length in each caudal vertebra) ranges showing a mean of approximately 0.15–0.28 in both Apodemus species. Previous studies in lizards and rodents found autotomic inter-VB and intra-VB to be positioned in a specific small portion of the tail. However, we found that in field mice, inter-VB and intra-VB were widely distributed along the tail without a regular position. Therefore, it is suggested that both inter-VB and intra-VB as self-defense ways in Apodemus appear to be mere torn-off breakages rather than autotomies, due to certain fragilities in intra- and intervertebral structures.
{"title":"Caudal Vertebral Fragilities Related to Loss of a Tail Part in Two Species of the Japanese Field Mice","authors":"M. Iwasa, Atsushi Hasegawa","doi":"10.3106/ms2020-0056","DOIUrl":"https://doi.org/10.3106/ms2020-0056","url":null,"abstract":"Abstract. In the Japanese field mice, Apodemus argenteus and A. speciosus, loss of a tail part has often been observed under natural conditions. Such loss is considered a way of avoiding damage during physical accidents and attacks. Here, we studied the types of losses, types of caudal breakages, and breakage positions along the tail. The losses mainly consisted of intervertebral breakage (inter-VB) and intravertebral breakage (intra-VB). VB occurred widely along the tail in both Apodemus species and showed no specific tendency for the inter-VB positions. Intra-VB was confirmed at caudal vertebrae of the middle portion of the tail, consisting of vertebrae with lower relative width (minimum width/maximum length in each caudal vertebra) ranges showing a mean of approximately 0.15–0.28 in both Apodemus species. Previous studies in lizards and rodents found autotomic inter-VB and intra-VB to be positioned in a specific small portion of the tail. However, we found that in field mice, inter-VB and intra-VB were widely distributed along the tail without a regular position. Therefore, it is suggested that both inter-VB and intra-VB as self-defense ways in Apodemus appear to be mere torn-off breakages rather than autotomies, due to certain fragilities in intra- and intervertebral structures.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"125 - 131"},"PeriodicalIF":1.0,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49195077","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 purpose of the present study was to determine whether and how the fruit-foraging behaviors of two frugivorous carnivorans, the raccoon dog (Nyctereutes procyonoides) and Japanese badger (Meles anakuma), are influenced by the presence of humans. In the first investigation, we contrasted the frequency and duration of foraging visits to fruit-bearing trees in an urban forest and a mountain forest. In the second investigation, we employed a modeling approach to ascertain whether the degree of shelter affected tree selection in the urban forest by these frugivorous species. The results of the first investigation showed that both species foraged almost solely at night in the urban forest and had significantly shorter visit times in the urban forest than in the mountain forest. The second investigation revealed that both species selected to forage in sheltered places where the forest floor was covered with vegetation. We found that fruit production did not affect tree choice in these places, indicating that the mammals prioritize avoiding humans over effective foraging in places with more plentiful fruits. These tendencies to forage at night and in areas with adequate shelter indicate that these species have adapted their behaviors to avoid humans in urban environments.
{"title":"Effects of Human Activity on the Fallen-Fruit Foraging Behavior of Carnivoran Species in an Urban Forest","authors":"S. Ōsugi, Bruna Elisa Trentin, S. Koike","doi":"10.3106/ms2021-0041","DOIUrl":"https://doi.org/10.3106/ms2021-0041","url":null,"abstract":"Abstract. The purpose of the present study was to determine whether and how the fruit-foraging behaviors of two frugivorous carnivorans, the raccoon dog (Nyctereutes procyonoides) and Japanese badger (Meles anakuma), are influenced by the presence of humans. In the first investigation, we contrasted the frequency and duration of foraging visits to fruit-bearing trees in an urban forest and a mountain forest. In the second investigation, we employed a modeling approach to ascertain whether the degree of shelter affected tree selection in the urban forest by these frugivorous species. The results of the first investigation showed that both species foraged almost solely at night in the urban forest and had significantly shorter visit times in the urban forest than in the mountain forest. The second investigation revealed that both species selected to forage in sheltered places where the forest floor was covered with vegetation. We found that fruit production did not affect tree choice in these places, indicating that the mammals prioritize avoiding humans over effective foraging in places with more plentiful fruits. These tendencies to forage at night and in areas with adequate shelter indicate that these species have adapted their behaviors to avoid humans in urban environments.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"113 - 123"},"PeriodicalIF":1.0,"publicationDate":"2022-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42436452","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}
in a second language We added a system that allows an abstract in a second language. The main purpose of this was to eliminate communication gaps between industry, government, academia, and the public, due to the exclusive use of English in the scientific community. I believe that many people, especially in education and wildlife conservation and manage2 Mammal Study 47 (2022) ment, are interested in the contents of Mammal Study, but do not speak English. Similarly, there must be authors who would like to share their findings with non-English readers. Policy makers usually make decisions in their own language, while the public do not always use English in their daily lives and social activities. Nevertheless, they need Mammal Study. Adding an abstract in a second language could facilitate internationalization by helping people to learn about studies that may be relevant to them. Although it seems paradoxical, admitting diversity can be a useful way to internationalize Mammal Study by eliminating communication gaps. See the Instructions to Authors for more details regarding this addition. Note that the Editor-in-Chief will reject an abstract in a second language if the content is deemed to differ sufficiently from the English abstract or is otherwise unable to verify the content of the second abstract.
{"title":"Editorial","authors":"J. Sato","doi":"10.3106/47-1-e","DOIUrl":"https://doi.org/10.3106/47-1-e","url":null,"abstract":"in a second language We added a system that allows an abstract in a second language. The main purpose of this was to eliminate communication gaps between industry, government, academia, and the public, due to the exclusive use of English in the scientific community. I believe that many people, especially in education and wildlife conservation and manage2 Mammal Study 47 (2022) ment, are interested in the contents of Mammal Study, but do not speak English. Similarly, there must be authors who would like to share their findings with non-English readers. Policy makers usually make decisions in their own language, while the public do not always use English in their daily lives and social activities. Nevertheless, they need Mammal Study. Adding an abstract in a second language could facilitate internationalization by helping people to learn about studies that may be relevant to them. Although it seems paradoxical, admitting diversity can be a useful way to internationalize Mammal Study by eliminating communication gaps. See the Instructions to Authors for more details regarding this addition. Note that the Editor-in-Chief will reject an abstract in a second language if the content is deemed to differ sufficiently from the English abstract or is otherwise unable to verify the content of the second abstract.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"1 - 2"},"PeriodicalIF":1.0,"publicationDate":"2022-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45477667","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. Benten-Jima Rock, located off Cape Soya, Hokkaido, has been a Steller sea lion (SSL; Eumetopias jubatus) winter haulout for decades. The animals usually occupy the site from October to May. Observations have been sporadic, although the population count started to increase in 2005. We have monitored SSL numbers since 2012 using several survey methods, such as observation by direct counting and remote archival cameras. Since these data were not sufficient, owing to blind spots, we started using unmanned aerial vehicle (UAV) surveys in 2016 and corrected the previously collected data. Using these methods, a considerable number of SSLs were observed at Benten-Jima Rock during 2016–2017. The maximum number of SSLs was 3158 on land and 3056 in the water near the site, as counted from UAV images on May 2, 2017. Based on hot brand marks, we found that Benten-Jima Rock hosted SSLs from all ten main rookeries along the Asian coast. The majority (∼60%) were from Tuleny Island near the east coast of Sakhalin. The cause of this extraordinary increase in SSL numbers at Benten-Jima Rock remains unclear and requires further monitoring and research.
{"title":"Origin and Abundance of Steller Sea Lions (Eumetopias jubatus) in Winter Haulout at Benten-Jima Rock Off Cape Soya, Hokkaido, Japan between 2012–2017","authors":"Y. Goto, Takeomi Isono, Shun Ikuta, V. Burkanov","doi":"10.3106/ms2020-0029","DOIUrl":"https://doi.org/10.3106/ms2020-0029","url":null,"abstract":"Abstract. Benten-Jima Rock, located off Cape Soya, Hokkaido, has been a Steller sea lion (SSL; Eumetopias jubatus) winter haulout for decades. The animals usually occupy the site from October to May. Observations have been sporadic, although the population count started to increase in 2005. We have monitored SSL numbers since 2012 using several survey methods, such as observation by direct counting and remote archival cameras. Since these data were not sufficient, owing to blind spots, we started using unmanned aerial vehicle (UAV) surveys in 2016 and corrected the previously collected data. Using these methods, a considerable number of SSLs were observed at Benten-Jima Rock during 2016–2017. The maximum number of SSLs was 3158 on land and 3056 in the water near the site, as counted from UAV images on May 2, 2017. Based on hot brand marks, we found that Benten-Jima Rock hosted SSLs from all ten main rookeries along the Asian coast. The majority (∼60%) were from Tuleny Island near the east coast of Sakhalin. The cause of this extraordinary increase in SSL numbers at Benten-Jima Rock remains unclear and requires further monitoring and research.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"87 - 101"},"PeriodicalIF":1.0,"publicationDate":"2022-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44966037","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}
Michiya Sano, Ayako Kawanabe, Y. Kurosawa, Yusuke Suzuki, M. Takeda, Tomoaki Nakamura, H. Iwata, T. Kuwayama, K. Shirasuna
Abstract. Cryopreservation of somatic tissues and cells can be applied to biodiversity conservation. Although vitrification is widely used for tissue cryopreservation, it is challenging to obtain viable cells in facilities that lack adequate experimental tools, such as zoos. In this study, we established a simple tissue cryopreservation method for obtaining viable cells. Using mouse tissues of the ears and skin, we explored the conditions suitable for cryopreservation. After freezing, the tissues were thawed, and the cells were isolated. The tissues were then cut into small pieces to obtain viable cells. The use of a cryopreservative solution and freezing at –80°C increased the probability of obtaining viable cells. Viable cells were obtained and cultured even after the ear tissues were stored at room temperature for 24 h. Our method allowed primary cells to be isolated and cultured from ear tissues of dead animal. Further, we examined whether cells isolated from cryopreserved tissues could be studied in vitro. We found that treatment with lipopolysaccharides and Poly I:C increased the mRNA expression of pro-inflammatory cytokines in wild boar cells. These data suggest that the simple cryopreservation method developed here can be applied to biodiversity conservation and basic science studies of wild animal cells.
{"title":"A Simple Cryopreservation Method for Efficient Isolation of Live Cells from Dead Animals","authors":"Michiya Sano, Ayako Kawanabe, Y. Kurosawa, Yusuke Suzuki, M. Takeda, Tomoaki Nakamura, H. Iwata, T. Kuwayama, K. Shirasuna","doi":"10.3106/ms2021-0019","DOIUrl":"https://doi.org/10.3106/ms2021-0019","url":null,"abstract":"Abstract. Cryopreservation of somatic tissues and cells can be applied to biodiversity conservation. Although vitrification is widely used for tissue cryopreservation, it is challenging to obtain viable cells in facilities that lack adequate experimental tools, such as zoos. In this study, we established a simple tissue cryopreservation method for obtaining viable cells. Using mouse tissues of the ears and skin, we explored the conditions suitable for cryopreservation. After freezing, the tissues were thawed, and the cells were isolated. The tissues were then cut into small pieces to obtain viable cells. The use of a cryopreservative solution and freezing at –80°C increased the probability of obtaining viable cells. Viable cells were obtained and cultured even after the ear tissues were stored at room temperature for 24 h. Our method allowed primary cells to be isolated and cultured from ear tissues of dead animal. Further, we examined whether cells isolated from cryopreserved tissues could be studied in vitro. We found that treatment with lipopolysaccharides and Poly I:C increased the mRNA expression of pro-inflammatory cytokines in wild boar cells. These data suggest that the simple cryopreservation method developed here can be applied to biodiversity conservation and basic science studies of wild animal cells.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"103 - 111"},"PeriodicalIF":1.0,"publicationDate":"2022-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43869351","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. Hybrid cetaceans occur in both captive and natural environments. This study is the first to describe the external morphological and genetic characterizations of natural intrageneric hybridization between the common bottlenose dolphin, Tursiops truncatus, and the Indo-Pacific bottlenose dolphin, T. aduncus, in Japanese waters. In November 2019, a stray dolphin was seen in Moriura Bay, Wakayama, Japan, and was a male that measured 241.5 cm in body length in July 2020, after an incidental catch in February 2020. Moderate speckles in the genital area of the dolphin were observed, which is a characteristic of T. aduncus. The dolphin had 22–23 pairs of teeth in each jaw, a quantity consistent for both species. The length of the rostrum and the size of flippers were within the range of T. aduncus. The mitochondrial DNA D-loop region haplotype was 99% homology with those from T. aduncus found in Chinese and Japanese waters. Microsatellite analysis revealed that the dolphin contained ratios of approximately 50% of both T. truncatus and T. aduncus lineages; the dolphin could therefore be an F1 hybrid between a female T. aduncus and a male T. truncatus. Further genetic studies are required to elucidate the origin of this hybrid dolphin.
{"title":"External Morphological and Molecular Evidence of Natural Intrageneric Hybridization between Common and Indo-Pacific Bottlenose Dolphins (Tursiops truncatus × T. aduncus) from Japanese Waters","authors":"Daiki Inamori, Yuki F. Kita, Noriko Funasaka","doi":"10.3106/ms2021-0039","DOIUrl":"https://doi.org/10.3106/ms2021-0039","url":null,"abstract":"Abstract. Hybrid cetaceans occur in both captive and natural environments. This study is the first to describe the external morphological and genetic characterizations of natural intrageneric hybridization between the common bottlenose dolphin, Tursiops truncatus, and the Indo-Pacific bottlenose dolphin, T. aduncus, in Japanese waters. In November 2019, a stray dolphin was seen in Moriura Bay, Wakayama, Japan, and was a male that measured 241.5 cm in body length in July 2020, after an incidental catch in February 2020. Moderate speckles in the genital area of the dolphin were observed, which is a characteristic of T. aduncus. The dolphin had 22–23 pairs of teeth in each jaw, a quantity consistent for both species. The length of the rostrum and the size of flippers were within the range of T. aduncus. The mitochondrial DNA D-loop region haplotype was 99% homology with those from T. aduncus found in Chinese and Japanese waters. Microsatellite analysis revealed that the dolphin contained ratios of approximately 50% of both T. truncatus and T. aduncus lineages; the dolphin could therefore be an F1 hybrid between a female T. aduncus and a male T. truncatus. Further genetic studies are required to elucidate the origin of this hybrid dolphin.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"133 - 140"},"PeriodicalIF":1.0,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42861629","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. To estimate the reproductive schedule of the Okinawa spiny rat on the basis of its body size distribution, we developed a nest box with an auto-trigger camera. Three camera-installed nest boxes were used in the field in the northern part of Okinawa Island beginning in September 2015. The distance between eyes, an index of body size, was measured in 850 images of spiny rats. The reproductive schedule was estimated based on the emergence period of subadults. With the emergence of subadults, the distribution of body size index becomes a mixture of two normal distributions consisting of adults and subadults, so a Gaussian mixture model was employed to identify each distribution. The Gaussian mixture model revealed that the distribution of the estimated distance between eyes could be divided into two clusters, with a mixing ratio of 0.11 for Group 1 (subadult) and 0.89 for Group 2 (adult). Most individuals belonging to Group 1 appeared during the winter months of December to March, indicating that subadults were weaned primarily during this season. Consequently, reproduction of the Okinawa spiny rat is thought to be limited in autumn and winter.
{"title":"Development of a Camera-Installed Nest Box for Small Mammals and Its Application in Reproductive Schedule Estimation for the Okinawa Spiny Rat","authors":"Nobuhiko Kotaka, M. Yasuda, Takuya Shimada","doi":"10.3106/ms2021-0025","DOIUrl":"https://doi.org/10.3106/ms2021-0025","url":null,"abstract":"Abstract. To estimate the reproductive schedule of the Okinawa spiny rat on the basis of its body size distribution, we developed a nest box with an auto-trigger camera. Three camera-installed nest boxes were used in the field in the northern part of Okinawa Island beginning in September 2015. The distance between eyes, an index of body size, was measured in 850 images of spiny rats. The reproductive schedule was estimated based on the emergence period of subadults. With the emergence of subadults, the distribution of body size index becomes a mixture of two normal distributions consisting of adults and subadults, so a Gaussian mixture model was employed to identify each distribution. The Gaussian mixture model revealed that the distribution of the estimated distance between eyes could be divided into two clusters, with a mixing ratio of 0.11 for Group 1 (subadult) and 0.89 for Group 2 (adult). Most individuals belonging to Group 1 appeared during the winter months of December to March, indicating that subadults were weaned primarily during this season. Consequently, reproduction of the Okinawa spiny rat is thought to be limited in autumn and winter.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"77 - 85"},"PeriodicalIF":1.0,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48132098","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 analyzed the stomach contents of wild boars (Sus scrofa) inhabiting evergreen forests in western Japan and found that they were dependent on the masting of acorns of Castanopsis cuspidata. The increased availability of C. cuspidata acorns positively affected their consumption by wild boars. In the good mast years, wild boars consumed C. cuspidata acorns from November to June of the following year. No significant annual variation in body condition was detected, suggesting that alternative food resources (e.g., bamboo shoots) may have maintained the body condition of wild boars, even in poor mast years. A strong negative correlation was found between the consumption of C. cuspidata acorns and the amount of crop damage to vegetables. This study revealed the wild boar as a pulsed food resource feeder, which has not yet been identified in Japan, and emphasized the importance of considering C. cuspidata masting for designing effective strategies for mitigating crop damage.
{"title":"Contribution of Acorn Masting to Food Composition and Body Condition of and Crop Damage by Wild Boars (Sus scrofa) Inhabiting Evergreen Forests in Japan","authors":"Akitaka Omori, E. Hosoi","doi":"10.3106/ms2021-0024","DOIUrl":"https://doi.org/10.3106/ms2021-0024","url":null,"abstract":"Abstract. We analyzed the stomach contents of wild boars (Sus scrofa) inhabiting evergreen forests in western Japan and found that they were dependent on the masting of acorns of Castanopsis cuspidata. The increased availability of C. cuspidata acorns positively affected their consumption by wild boars. In the good mast years, wild boars consumed C. cuspidata acorns from November to June of the following year. No significant annual variation in body condition was detected, suggesting that alternative food resources (e.g., bamboo shoots) may have maintained the body condition of wild boars, even in poor mast years. A strong negative correlation was found between the consumption of C. cuspidata acorns and the amount of crop damage to vegetables. This study revealed the wild boar as a pulsed food resource feeder, which has not yet been identified in Japan, and emphasized the importance of considering C. cuspidata masting for designing effective strategies for mitigating crop damage.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"65 - 75"},"PeriodicalIF":1.0,"publicationDate":"2021-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44877326","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}
Takashi Ikeda, Satuski Nakamori, M. Ando, T. Shirakawa, T. Okamoto, Masatsugu Suzuki
Abstract. The diel activity pattern is a key factor in the coexistence mechanism of sympatric wild animals, enabling temporal niche partitioning. Although previous studies on sympatric ungulates (sika deer, Japanese serow, and wild boar) have reported dietary and spatial niche partitioning, temporal niche partitioning in these sympatric ungulates is not well understood. In this study, we aimed to elucidate the seasonal diel activity patterns of three sympatric ungulates in Gifu Prefecture, Japan, where they have been sympatrically distributed since 1978. We placed 21 camera traps from August 2017 to November 2019, and investigated diel activity patterns and photographic frequencies over three time periods (daytime, night-time, and twilight). Although we found no seasonal changes in diel activity patterns of three ungulates, but patterns showed differences among species. While sika deer showed crepuscular activity, wild boars and Japanese serows showed nocturnal activity. In addition, Japanese serows showed temporal niche partitioning against sika deer. Consequently, we suggest that the relationship between sika deer and Japanese serow is competitive in terms of diel activity patterns.
{"title":"Seasonal Diel Activity Patterns of Three Sympatric Ungulates in Forested Area in Central Japan","authors":"Takashi Ikeda, Satuski Nakamori, M. Ando, T. Shirakawa, T. Okamoto, Masatsugu Suzuki","doi":"10.3106/ms2021-0031","DOIUrl":"https://doi.org/10.3106/ms2021-0031","url":null,"abstract":"Abstract. The diel activity pattern is a key factor in the coexistence mechanism of sympatric wild animals, enabling temporal niche partitioning. Although previous studies on sympatric ungulates (sika deer, Japanese serow, and wild boar) have reported dietary and spatial niche partitioning, temporal niche partitioning in these sympatric ungulates is not well understood. In this study, we aimed to elucidate the seasonal diel activity patterns of three sympatric ungulates in Gifu Prefecture, Japan, where they have been sympatrically distributed since 1978. We placed 21 camera traps from August 2017 to November 2019, and investigated diel activity patterns and photographic frequencies over three time periods (daytime, night-time, and twilight). Although we found no seasonal changes in diel activity patterns of three ungulates, but patterns showed differences among species. While sika deer showed crepuscular activity, wild boars and Japanese serows showed nocturnal activity. In addition, Japanese serows showed temporal niche partitioning against sika deer. Consequently, we suggest that the relationship between sika deer and Japanese serow is competitive in terms of diel activity patterns.","PeriodicalId":49891,"journal":{"name":"Mammal Study","volume":"47 1","pages":"47 - 56"},"PeriodicalIF":1.0,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43699395","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}