研究者データベース
髙田 隼人TAKADA Hayatoﾀｶﾀﾞ ﾊﾔﾄ
| ■所属部署名 | 農学部附属野生動物管理教育研究センター | |||
| ■職名 | 特任准教授 | |||
Last Updated :2026/07/29
業績情報
氏名・連絡先
氏名
ﾀｶﾀﾞ ﾊﾔﾄ, 髙田 隼人, TAKADA Hayato個人ホームページ
https://wildlbehavecol.wixsite.com/labo
主たる所属・職名
農学部附属野生動物管理教育研究センター, 特任准教授
学位
教育・研究活動状況
科学研究費助成事業
- 若手研究
カモシカが減るのはシカのせい？行動・栄養・ホルモン分析を用いた種間競争の実態解明
自 2022年, 至 2024年 - 国際共同研究加速基金（国際共同研究強化(A)）
原始的森林性有蹄類カモシカ属の保全に向けた行動生態学的研究
自 2024年, 至 2026年
論文
- Dietary partitioning in two gleaning bats, Japanese long-eared bats ( Plecotus sacrimontis) and Ussuri tube-nosed bats ( Murina ussuriensis): consuming insects of same order but different developmental stages
Takada, Hayato; Sato, Akiyoshi; Katsuta, Setsuko; Nakamura, Keita; Ohwaki, Atsushi; Kane, Yuto; Hayakawa, Takashi; Inoue, Eiji
ANIMAL BIOLOGY
BRILL
Knowledge of diet is essential for understanding the mechanism of coexistence among multiple species. Two gleaning bats, the Japanese long-eared bat ( Plecotus sacrimontis) ) and the Ussuri tube- nosed bat ( Murina ussuriensis), ), have similar eco-morphological traits, but it is unclear how they coexist. We examined the seasonal fecal contents of these species in the cool temperate forest of Mount Fuji, central Japan, using microscopical analysis. Long-eared bats, which have larger pinnae, more frequently consumed tympanate insects, such as adult moths, during early spring to summer, whereas tube-nosed bats, which have smaller pinnae, more frequently consumed non-tympanate insects such as caterpillars and grasshoppers, during spring to early summer and summer to autumn, respectively. Interestingly, they consumed insects of the same order but different developmental stages (i.e., adult moths and caterpillars) during spring to early summer, which revelation was made possible by microscopic analysis, not by DNA analysis. These differences suggest that the large pinna of the long-eared bat is an adaptation for preying on tympanate insects, which resulted in food resource partitioning. Additionally, to the best of our knowledge, the Ussuri tube-nosed bat can be considered one of the bats that most frequently eats caterpillars.
2024年09月, 研究論文（学術雑誌）, 共同, 74, 3, 1570-7555, DOI(公開)(r-map), 285, 299 - Tree-Climbing Behavior of a Forest-Dwelling Ungulate: The Formosan Serow
Takada, Hayato; Sun, Nick Ching-Min; Liang, Yu-Jen; Liu, Jen-Hao; Liu, Ching-Kuo; Pei, Kurtis Jai-Chyi
ANIMALS
MDPI
Tree climbing is an extremely rare behavior among ungulates and has rarely been reported in forest-dwelling ungulates. We collected 15 tree-climbing records of Formosan serows, mainly from social media platforms. They climbed trees to forage throughout the year in many locations in Taiwan. This is the first report of tree-climbing behavior in the Formosan serow, which is typically a forest dweller. Ungulates are terrestrial herbivores, basically adapted to running fast on the ground; tree-climbing behavior has been reported only in seven species, and five of them live in open habitats (Capra hircus, C. aegagrus, C. falconeri, C. cylindricornis, Oreotragus oreotragus). Tree-climbing behavior may also be evolved in ungulates inhabiting dense forests with abundant trees; however, this has rarely been reported in such species (Moschus leucogaster, M. moschiferus), probably due to the difficulty of observing in the wild. The numerous publicly available records in social networks hold potentially valuable information on the atypical behaviors of wild ungulates. Here, we explored the tree-climbing behavior of a forest-dwelling ungulate, the Formosan serow in Taiwan, a subtropical island, by extracting information from online social media platforms. We researched images and videos of Formosan serows through Facebook and YouTube and collected a total of 15 tree-climbing events. In these materials, Formosan serows climbed 10 tree species, including evergreen coniferous and broad-leaved trees, and a variety of parts, ranging in height from 0.6 to 4 m, and from branches of shrubs to trunks of tall trees. Tree-climbing behavior was recorded throughout Taiwan and from lowlands to subalpine zones, suggesting that tree climbing may be a common behavior in this species. Foraging while climbing trees was frequently observed (53.3%), suggesting that the purpose or benefit for climbing is to obtain additional food other than plants growing near the ground surface. In contrast to other tree-climbing ungulates, Formosan serows climbed trees not only in winter, but also in other seasons, when food is relatively abundant. This is the first scientific report of tree-climbing behavior in the Formosan serow that is typically a forest dweller.
2024年08月, 研究論文（学術雑誌）, 共同, 14, 15, 2076-2615, DOI(公開)(r-map) - Effects of Human Harvesting, Residences, and Forage Abundance on Deer Spatial Distribution
Takada, Hayato; Nakamura, Keita
ANIMALS
MDPI
Investigating the spatial distribution of wildlife contributes to understanding the adaptation of wildlife and conservation management. We assessed the summer spatial distribution of sika deer Cervus nippon in relation to human harvesting and other factors, such as human residences, forage abundance, and cover. Spatial distribution of deer was significantly biased to non-harvesting areas and far from residential areas, suggesting that the deer avoid riskier spaces by establishing a landscape of fear. High-quality food resources (deciduous broad-leaved trees and forbs) were more abundant in harvesting areas than in non-harvesting areas, suggesting that foraging pressure by deer reduce them. However, deer frequently used higher dwarf bamboo abundance areas, suggesting that the dwarf bamboo is an alternative food resource in non-harvesting areas. Our results suggest that human activities shifted the spatial distribution of deer to areas far from human activities, such as subalpine/alpine zones, which may increase damage to vulnerable ecosystems due to severe foraging pressure. It has been known that harvesting by humans strongly influences individual within-home range habitat selection of many deer species; however, little is known about the effect of harvesting on coarse-scale habitat selection (i.e., spatial distribution). We examined the summer spatial distribution of sika deer Cervus nippon in relation to human harvesting and other factors, such as human residences, forage abundance, and cover, using pellet group counts at Mount Fuji, central Japan, in 2018. In the study area, harvesting is conducted at medium elevation areas throughout the year, but not at high or low elevation areas where access is difficult or harvesting is prohibited. Spatial distribution of deer was significantly biased to non-harvesting areas and far from residential areas, suggesting that they avoid riskier spaces by establishing a landscape of fear. High-quality food resources (deciduous broad-leaved trees and forbs) were more abundant in harvesting areas than in non-harvesting areas, suggesting that foraging pressure by deer reduce them. However, there were no differences in abundances of more fibrous dwarf bamboo between harvesting and non-harvesting areas, and spatial distribution of deer was significantly biased to higher dwarf bamboo abundance areas, suggesting that the dwarf bamboo is an alternative food resource in non-harvesting areas where supplies of high-quality food were limited. Our results suggest that human harvesting pressure and residences shifted the spatial distribution of deer from the montane forests to subalpine/alpine zones, which may increase damage to vulnerable ecosystems due to severe foraging pressure.
2024年07月, 研究論文（学術雑誌）, 共同, 14, 13, 2076-2615, DOI(公開)(r-map) - Genetic Analysis Reveals Dispersal Patterns of Japanese Serow in Two Different Habitats of a Mountainous Region
Hori, Maiko; Takada, Hayato; Nakane, Yuki; Minami, Masato; Inoue, Eiji
ZOOLOGICAL SCIENCE
ZOOLOGICAL SOC JAPAN
Dispersal increases the costs of feeding and predation risk in the new environment and is reported to be biased toward habitats similar to the natal region in some mammals. The benefits and costs of dispersal often differ between sexes, and most mammals show male-biased dispersal in relation to a polygamous mating system. Japanese serow is generally a solitary and monogamous species. However, recent studies have shown that the sociality of serows on Mt. Asama differs between habitat types. In the mountain forests with low forage availability, solitary habits and social monogamy were observed, while, in alpine grasslands, female grouping and social polygyny were observed, which is probably due to abundant forage availability. We investigated the effects of habitat characteristics and sociality on the dispersal of serows using fecal and tissue samples from two different habitats on Mt. Asama. The Fst value between the two areas was significantly positive, and the mean relatedness within areas was significantly higher than that between areas, which suggests limited gene flow and natal habitat-biased dispersal. Bayesian clustering analysis showed unidirectional gene flow from forest to grassland, which was probably due to the high forage availability of the grassland. Analyses of the assignment index and mean relatedness did not show male-biased dispersal, even in the grassland, where serows were polygynous. Thus, polygyny in the grassland is not linked to male- biased dispersal. In summary, our study suggests that dispersal patterns in Japanese serows are affected by habitat rather than social differences.
2024年04月, 研究論文（学術雑誌）, 共同, 41, 2, 0289-0003, DOI(公開)(r-map), 201, 209 - Diet selection of a solitary forest-dwelling ungulate, the Japanese serow (Capricornis crispus), in cool temperate forest
Takada, Hayato; Nakamura, Keita; Minami, Masato
MAMMAL STUDY
MAMMALOGICAL SOC JAPAN
To determine the diet selection of a forest-dwelling ungulate, the Japanese serow (Capricornis crispus), we investigated its diet composition in relation to forage availability using direct observation of foraging behavior for individually identified three adult males in three seasons (spring, autumn, and winter) over two years in the cool temperate forests of Mt. Asama, central Japan. We found that they selected deciduous broad-leaved trees (leaves, fruits, twigs, and buds), forbs (leaves and flowers), and ferns (leaves) and avoided leaves of graminoids and coniferous trees throughout the study periods. Our findings clearly indicate that serows are typical browsers, selecting more digestible food plants. Unexpectedly, our analyses indicated a higher selectivity for ferns than deciduous broad-leaved trees, especially in winter. We also showed that diet composition was significantly different among individuals, but there was little difference in diet selectivity among individuals, suggesting that interindividual differences in diet are affected by forage availability within each individual's home range.
2024年03月, 研究論文（学術雑誌）, 共同, 49, 2, 1343-4152, DOI(公開)(r-map), 97, 105 - Seasonal diets of two rhinolophid bats, Rhinolophus nippon and Rhinolophus cornutus, in the southern Japanese Alps
Takada, Hayato; Sato, Akiyoshi; Katsuta, Setsuko
ANIMAL BIOLOGY
BRILL
Knowledge of diets is important for understanding species ecology and the mechanism of coexistence of multiple closely related species. Two rhinolophid bats, the greater Japanese horseshoe bat (Rhi-nolophus nippon) and the little Japanese horseshoe bat (Rhinolophus cornutus), occur in Japan, but little is known about their diets and interspecific interactions regarding food resources. In this study, we examined the fecal contents of these two species in the Southern Japanese Alps by microscopic analysis over multiple seasons. R. cornutus, which have more skillful flight, consumed nonvolant insects (caterpillars and spiders), whereas R. nippon did not; this indicates that R. cornutus can glean prey better than R. nippon. The larger-bodied R. nippon more frequently consumed hard-bodied beetles, whereas the smaller-bodied R. cornutus more frequently consumed soft-bodied dipterans and neuropterans. Body size differences influenced flight ability and bite force, which resulted in food resource partitioning and enabled multispecies coexistence of these closely related bats. A R. nippon nursery colony consumed a wider variety of insects, such as beetles, moths, and dipterans, during the pregnancy and lactation periods; however, after lactation, they showed a beetle-dependent diet, and before hibernation they again consumed various food resources. A R. cornutus non-nursery colony frequently consumed dipterans and moths in spring; dipterans, moths, and neuropterans in autumn; and moths and neuropterans in winter. These seasonal changes in diet seemed to be related to food supply or reproductive status.
2023年11月, 研究論文（学術雑誌）, 共同, 73, 4, 1570-7555, DOI(公開)(r-map), 363, 378 - Overlap in habitat use and activity patterns between sika deer (Cervus nippon) and Japanese serows (Capricornis crispus) in subalpine habitats: exploitative competition rather than direct interference?
Takada, Hayato; Nakamura, Keita
CANADIAN JOURNAL OF ZOOLOGY
CANADIAN SCIENCE PUBLISHING
Examining multiple niche relationships, such as habitat use and activity patterns, between sympatric species contributes to an understanding of the mechanisms of coexistence and competition. Sika deer (Cervus nippon Temminck, 1838) and Japanese serows (Capricornis crispus (Temminck, 1836)) often show different habitat use, and diversity in vegetation and topography seems to facilitate their coexistence. Conversely, their habitat use may overlap in areas with low-diversity habitats; however, this remains unstudied. Moreover, whether they spatiotemporally avoid each other to reduce direct interference is unclear. We examined the fine-scale patterns of habitat use and activity of deer and serows in the subalpine forests of Mount Fuji, which have low-diversity habitats, using camera trapping data over 3 years. Deer and serow habitat niches largely overlapped, especially in summer (92%-94%) and autumn (89%-91%), suggesting that low-diversity habitats facilitate overlapping habitat use. Both species selected areas frequently used by the other during spring to autumn and their temporal niches largely overlapped, especially in summer (88%) and autumn (83%), suggesting that they do not spatiotemporally avoid each other (i.e., there is no direct interference). Rapid range expansion of deer into these subalpine habitats may exclude native serows through resource exploitative competition rather than interference competition.
2023年07月12日, 研究論文（学術雑誌）, 共同, 0008-4301, DOI(公開)(r-map) - Dietary partitioning and competition between sika deer and Japanese serows in high elevation habitats
Hiruma, Mitsuko; Takada, Hayato; Washida, Akane; Koike, Shinsuke
MAMMAL RESEARCH
SPRINGER HEIDELBERG
How environmental conditions promote interspecific niche overlap and the occurrence of competition has long intrigued ecologists. In native ungulate assemblages, dietary partitioning based on interspecific differences in diet preferences has often been reported, but dietary overlap indicating competition is relatively rare. In Japan, native sika deer (Cervus nippon) have invaded high-elevation mountain areas and negatively affected the vegetation there, whereas native Japanese serows (Capricornis crispus) have declined in these areas. However, diet-related interspecific relationships between these species remain unclear in these areas. We examined the diets of deer and serows, and the forage availability in a subalpine forest and an alpine desert of Mt. Fuji, central Japan. The subalpine forest provided both graminoids and coniferous trees, while the alpine desert provided a homogeneous supply of dicot leaves, and forage abundance of both habitats was quite limited. In the subalpine forest, deer fed mainly on graminoids while serows fed mainly on conifer leaves, suggesting partitioning of food resources. By contrast, in the alpine desert, both species fed mainly on dicot leaves, resulting in dietary overlap. We show for the first time that the diets of these two species overlap when shared food resources are limited, suggesting that food resource competition is likely to occur in the alpine desert. These results suggest that food resource competition can occur when both food resource diversity and abundance are limited, even among native species with different diet preferences.
2023年07月, 研究論文（学術雑誌）, 共同, 68, 3, 2199-2401, DOI(公開)(r-map), 305, 315 - Unique spatial behavior of the Japanese serow (Capricornis crispus) in the open mountains of Mt. Fuji
Takada, Hayato
ACTA ETHOLOGICA
SPRINGER HEIDELBERG
The Japanese serow (Capricornis crispus) exhibits spatial behavior adapted to forest habitats with relatively stable food supply and climatic conditions, such as sedentary habits, small home ranges, and little seasonal variation in habitat selection. However, investigations have not previously been conducted in open mountainous habitats with high seasonal variability. Therefore, I examined spatial behavior of the Japanese serow in an open mountainous region of Mt. Fuji, central Japan, based on GPS location data. These mountain-dwelling serows had much larger annual home ranges (female: 316.5 ha, male: 373.1 ha) compared with forest-dwelling populations. Spring and summer home range sizes were the largest, and winter home range size was the smallest, ranging from 20.3%-56.1% of maximum. Limited forage and harsh climatic conditions in winter seemed to drive such energy-minimizing behavioral strategies. Selection of vegetation types and elevation varied seasonally, likely because of changes in forage availability and climate conditions. These spatial behaviors in mountain-dwelling serows resemble those of several related mountain ungulates, implying that these behaviors are adaptations to highly seasonal open mountainous habitats. My findings suggest that the main factors affecting spatial behavior are habitat characteristics, such as climate, forage abundance, and seasonality. These findings provide support for an ecological pattern in ungulate spatial behavior whereby closed habitats promote small and stable home ranges, whereas open habitats promote large and seasonally fluctuating home ranges.
2023年06月, 研究論文（学術雑誌）, 単独, 26, 2, 0873-9749, DOI(公開)(r-map), 127, 132 - Behavioural interactions between sika deer and Japanese serows: are larger and gregarious ungulates dominant?
Takada, H.; Yano, R.; Watanabe, H.; Ohuchi, R.; Kanno, T.; Washida, A.; Nakamura, K.; Tezuka, N.; Shimodoumae, D.; Minami, M.
BEHAVIOUR
BRILL
In ungulate assemblages, although interspecific differences in body size and gregariousness are thought to have a direct impact on winning or losing in interference competition, this has not been fully investigated. We observed a total of 64 instances of interspecific contact between larger -gregarious sika deer and smaller-solitary Japanese serows over eight years field observations. Deer-to-serow aggression were never observed. Whereas, serows showed antagonistic behaviour, such as walk push and chasing, to deer, but could rarely displace deer. Serows showed higher alertness to deer than deer did to serows. These results suggest that larger-gregarious ungulates do not necessarily exclude smaller-solitary ones and serows are sensitive to the presence of deer. Differences in aggressiveness and alertness between deer and serows may reflect differences in territoriality: serows may be more sensitive to the invasion of deer into their territory. Serows' sensitivity to deer may have a negative effect on their population.
2023年06月, 研究論文（学術雑誌）, 共同, 160, 7, 0005-7959, DOI(公開)(r-map), 661, 681 - Evolution from monogamy to polygyny: insights from the solitary Japanese serow
Takada, Hayato; Washida, Akane; Yano, Risako; Tezuka, Natsuki; Minami, Masato
BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY
SPRINGER
Understanding the main factors driving the evolution of mating systems is a major goal of behavioral ecology. In ungulates, the transition from forests to open habitats and the accompanying clustered spatial distribution of females are thought to have promoted an evolutionary shift from monogamy to polygyny. However, no field-based studies to date have tested in the field whether such changes in ecological conditions promote a shift from monogamy to polygyny. We investigated mating systems of the Japanese serow, which is an evolutionarily ancestral and solitary species among caprids, living in the area with subalpine forest and alpine meadows over 7 years. We evaluated the effects of habitat characteristics on mating systems using within population comparisons. In this site, females form solitary territories in subalpine forests but group territories in alpine meadows. Males defended most of their home ranges as territories, and both social monogamy (29.6%; one male with one female) and polygyny (70.4%; one male with 2-5 females) were observed. Males in alpine meadows formed mating units with more females, whereas males in subalpine forests formed mating units with single females. We show that open habitats promote the transition from social monogamy to polygyny and a higher degree of social polygyny. Our findings suggest that the main factor affecting the mating system is the spatial dispersion of females (solitary territory or group territory), which depends on habitat structure (closed or open).Significance statementThe Japanese serow is an ungulate that mainly inhabits forests and is assumed to possess the ancestral social systems for caprids, such as solitary and monogamous with territory. We found that open habitats, such as alpine meadows, promote the transition from monogamous to polygynous territory in the Japanese serow. In the study site, alpine meadows promote the transition from solitary territory to group territory of females. Thus, our results suggest that the main factor affecting the mating system is the spatial dispersion of females (solitary or group territory), which depends on habitat structure (subalpine forests or alpine meadows). Our findings provide evidence for a social evolutionary pattern in caprids, whereby the spread of forest-dwelling ancestors into open mountains promote evolution from social monogamy to polygyny.
2023年03月, 研究論文（学術雑誌）, 共同, 77, 3, 0340-5443, DOI(公開)(r-map) - Food habits of two species of tube-nosed bats, Murina hilgendorfi and Murina ussuriensis, in Hayakawa, central Japan
Takada, Hayato; Sato, Akiyoshi; Katsuta, Setsuko
ANIMAL BIOLOGY
BRILL
Knowledge of food habits is essential for understanding the life history of a species; however, such information about the enigmatic Murina genus of bats is little known. In this study, we examined the food habits of Murina hilgendorfi and Murina ussuriensis over four years in Hayakawa, central Japan, using traditional morphological fecal analysis. Fragments of arthropods of six orders (five identified families), and of five orders (five identified families), were found in the feces of M. hilgendorfi and M. ussuriensis, respectively. Both species consumed wingless arthropods (caterpillars and spiders), insects that rarely fly (ground beetles and bush crickets), or diurnal insects (dragonflies and hover flies; i.e., that are resting at night) during the night, which is a clear indication of gleaning behavior in these bats. In spring, the large-bodied M. hilgendorfi more frequently consumed hard-bodied insects such as beetles and bush crickets, whereas the small-bodied M. ussuriensis more frequently consumed soft-bodied insects such as caterpillars, moths, spiders, and dipterans, suggesting that the body size difference influences their food habits, which may have contributed to food resource partitioning between these closely related bats. For M. hilgendorfi, beetles were the main prey in spring and autumn, while caterpillars and grasshoppers were more frequently consumed in spring and autumn, respectively, suggesting that they may have changed prey items according to seasonal fluctuations in food availability. To our knowledge, this study provides the first record of differences in the food habits of these two species.
2022年03月, 研究論文（学術雑誌）, 共同, 72, 1, 1570-7555, DOI(公開)(r-map), 1, 13 - Ecological drivers of population abundance of the Japanese serow in the absence of predation risk
Takada, Hayato; Washida, Akane; Yamasaki, Shuhei
EUROPEAN JOURNAL OF WILDLIFE RESEARCH
SPRINGER
In ungulates, population abundance is mainly influenced by forage condition, predation pressure, competitor abundances, and human activities; however, information about the effect of the escape terrain on the population abundance is still scarce. Some ungulate species often use areas with abundant escape terrain despite the absence of predators, indicating that the ghosts of predators past continue to affect their spatial behavior, and population abundance of such ungulates may also be influenced by the escape terrain. We examined population abundance of the Japanese serow (Capricornis crispus) in Mt. Fuji and its surrounding mountains with the absence of predators, including both natural and human hunters, in relation to forage condition, vegetation, escape terrain (steep slopes), potential competitor (sika deer Cervus nippon), and non-invasive human activities. The population abundance (pellet group numbers) of serows was higher in coniferous forests than in broad-leaved forests, and in areas with abundant dwarf bamboos and where high fecal nitrogen content was detected, suggesting that forage availability of dwarf bamboo and coniferous trees as well as forage quality influenced their abundance. Conversely, sika deer abundance and human residences did not affect the population abundance of serows, suggesting that the potential competitor and the non-invasive human activity may not have had a direct effect on the serow abundances. Moreover, the population abundance of serow was higher in areas with abundant escape terrain, suggesting that the ghosts of predators past may affect their abundance. Population abundance of serows may be low in areas with scarce escape terrains because fewer individuals settle in environments with minimal escape terrain.
2025年06月, 研究論文（学術雑誌）, 共同, 71, 3, 1612-4642, DOI(公開)(r-map) - Variation in the activity patterns of Japanese serow (Capricornis crispus) across different temporal scales
Selvarajah, Kushaal; Baek, Seung-Yun; Takada, Hayato; Kim, Dongmin; Yamada, Yusaku; Koike, Shinsuke
EUROPEAN JOURNAL OF WILDLIFE RESEARCH
SPRINGER
Movement and behavioral patterns of a species reflect its response and adaptation to the environment. These responses form diel activity patterns that can be further categorized into certain temporal niches, namely, diurnal, nocturnal, crepuscular, and cathemeral. The diel activity pattern of Japanese serow (Capricornis crispus) has mostly been studied using camera traps and direct observations, which might have introduced bias, particularly with nocturnal activities. This study aimed to investigate the diel activity pattern of Japanese serow and seasonal changes in it using built-in triaxis activity sensor GPS collars. This study was conducted in Tokyo, central Japan, with data collected from five individuals. Results showed significantly higher activity during day than that during night across all individuals. The absence of natural predators, such as the Japanese wolf (Canis lupus hodophylax), and direct human threats, like hunting, suggests limited selective pressure for regular activity pattern modification. Seasonally, activity peaked in spring and autumn. In spring, these peaks may be attributed to increased foraging for crude protein from shoot sprouts after colder months. In autumn (September to November), the peak in activity level may be attributed to mating behavior. Therefore, classification of behaviors using activity sensors can provide a better understanding of variations in activity level between sexes and at the population level. This study is the first to use activity sensors to understand the diel and seasonal activity patterns of Japanese serow, reflecting its novelty and effectiveness.
2025年11月03日, 研究論文（学術雑誌）, 共同, 71, 6, 1612-4642, DOI(公開)(r-map) - Competition between native ungulates: negative effects of sika deer (Cervus nippon) on foraging behavior, physiological stress, and population characteristics of Japanese serow (Capricornis crispus)
Takada, H.; Tezuka, N.; Yano, R.; Washida, A.; Hasegawa, T.; Yamazaki, K.
JOURNAL OF ZOOLOGY
WILEY
In coevolved native ungulate assemblages, the mechanisms underlying competition remain unclear because, to date, little direct evidence of competition exists. In high-elevation areas in Japan, the number of native Japanese serows (Capricornis crispus) has been decreasing as the number of native sika deer (Cervus nippon) increases. Here, we assessed the effects of deer on vegetation, vigilance and foraging behavior, physiological stress, and relative abundance and ratio of young individuals of serows throughout the warm season across two study sites with different deer densities and similar landscapes in high-elevation areas of Mount Asama, Central Japan. The abundance and diversity of palatable forage for serows (i.e., herbaceous forbs) were significantly lower in areas with abundant deer, suggesting that deer abundance reduced the vegetation quality for serows. Serow vigilance rate was significantly greater in areas with abundant deer, suggesting that the increased probability of encountering deer or of intraspecific aggression increased vigilance. Serow bite rate was significantly lower and their step rate was greater in areas with abundant deer, suggesting that lower availability of herbaceous forbs and higher vigilance reduced serow foraging efficiency. Levels of serow fecal cortisol metabolites were significantly greater in areas with abundant deer, suggesting that deer abundance and decreased foraging efficiency increased physiological stress of serows. The relative abundance and ratio of young individuals of serow populations were significantly lower in areas with abundant deer, suggesting that deer abundance negatively affected the serow population through both exploitative and interference competition. This is a rare case to show direct evidence and mechanisms of interspecific competition in native ungulate assemblages. Human alteration of ecosystem processes, such as the elimination of top predators and decreased human hunting pressure on deer, may determine changes in ecological relationships between serow and deer.
2025年08月, 研究論文（学術雑誌）, 共同, 326, 4, 0952-8369, DOI(公開)(r-map), 403, 413 - Sex and age differences in habitat use priorities of sika deer (Cervus nippon) in highly seasonal habitats of Mount Fuji
Nakamura, K.; Takada, H.; Koike, S.
BEHAVIOUR
BRILL
Sexually dimorphic ungulates often show differences in habitat use between sexes; however, information on seasonal changes in habitat use according to sex and the presence of offspring is scarce. This study aimed to clarify the seasonal differences in habitat use of sika deer (Cervus nippon) according to sex, age, and the presence of offspring in the highly seasonal habitats of the subalpine zone of Mount Fuji, Japan. Habitat use varied across seasons and substantial differences according to sex and the presence offspring were observed in summer. In summer, males frequently used habitats with abundant forage (forest edges). Conversely, while females without offspring frequently used habitats with abundant forage (forest edges) and safety (flat terrain), females with offspring preferred safer habitats (forest interior, areas far from mountain trails, and flat terrain) instead. These results revealed that males, females without fawns, and females with fawns prioritized food intake over safety, both food intake and safety, and safety, respectively. These patterns reflect differences in vulnerability to predation and in strategies to maximize reproductive success. The habitat use of females with fawns changed drastically from summer to autumn: in autumn, they prioritized not only safety but also food conditions, suggesting that their habitat use changed seasonally as vulnerability declined with fawn growth.
2025年06月, 研究論文（学術雑誌）, 共同, 162, 5, 0005-7959, DOI(公開)(r-map), 415, 429 - Unique dietary partitioning among three sympatric forest-dwelling ungulates in Taiwan deviates from the Jarman-Bell principle
Takada, Hayato; Liang, Yu-Jen; Sun, Nick Ching-Min; Pei, Kurtis Jai-Chyi
CONTRIBUTIONS TO ZOOLOGY
BRILL
The Jarman-Bell principle is considered a general concept in ecology, stating that larger-bodied ungulates tend to eat lower-quality forage (i.e. less digestible graminoids), whereas smaller-bodied ungulates tend to eat higher-quality forage (i.e. highly digestible browse and herbaceous forbs). This contributes to dietary niche segregation among sympatric ungulates of different body sizes. However, it is unclear whether this concept applies to forest-dwelling ungulates in subtropical regions. Therefore, to determine the interspecific relationships regarding dietary niche among the sympatric sambars (largest body size), muntjacs (smallest body size), and Formosan serows (intermediate body size) in the subtropical montane cloud forest of Yushan National Park (Taiwan), we investigated their seasonal diet through microscopic analysis of feces. We found that the proportions of graminoids were higher in sambar feces than in muntjac and serow feces, supporting the Jarman-Bell principle. The proportions of dicot leaves were highest in serow feces, followed by muntjac and sambar feces, which deviated from the Jarman-Bell principle. This may have been caused by the tree-climbing behavior of serows, which allows them access to the abundant leaves of higher trees that sambar and muntjacs cannot access. To the best of our knowledge, our findings are the first to suggest that unique behavioral traits, such as tree climbing, cause unique dietary partitioning of ungulates in subtropical zones.
2025年12月, 研究論文（学術雑誌）, 共同, 94, 5, 1383-4517, DOI(公開)(r-map), 461, 476 - Latrine ecology of a solitary ungulate, the Japanese serow: female-male communication site rather than territorial marking?
Takada, Hayato; Watanabe, Haruko; Yano, Risako; Tsukada, Hideharu
MAMMALIA
WALTER DE GRUYTER GMBH
The functions of latrines have been well studied in gregarious or pair-living territorial ungulates, however, there are no field-based studies on latrine behaviour of solitary ungulates with monogamous pair territories. We investigated latrine behaviour of the Japanese serow (Capricornis crispus), a solitary and monogamous species. The spatial patterns of latrines did not coincide with the serows' home range boundaries, and individuals of the same sex did not defecate at the same latrine (i.e., there was no countermarking), which suggests that latrines may not function as territorial marking. During the late-mating season, when males and females tend to live separately, the number of latrine visits by females increased and the probability of defecating was significantly higher, suggesting that females are the signallers, informing their oestrus status to males. Moreover, males also frequently visited the latrines, and latrine sniffing and overmarking were observed only during the late-mating season, suggesting that males may receive information about oestrus from the females' faeces. Obtaining information on female oestrus directly is difficult for solitary species in which sexes live separately. Although future studies would be required to confirm this hypothesis, our study suggests that latrines may have evolved as female-to-male communication sites in the Japanese serow.
2025年07月28日, 研究論文（学術雑誌）, 共同, 89, 4, 0025-1461, DOI(公開)(r-map), 382, 391
メディア報道
- 南アルプス山麓のコウモリ2種、体の大小による違いで食い分けて共存 東京農工大など
山梨県の南アルプス山麓の森に住み、見た目がそっくりで共通の特徴を持つ近縁のコウモリ2種が、体の大小による違いによって餌を食い分けて共存している可能性があることを、農工大の高田淳教授らが明らかにしたと、紹介される。
Science Portal
自 2023年12月06日, 至 2023年12月06日 - カモシカ威嚇 シカはシカト 両種遭遇時の行動 東農工大調査 通説反する「関係」 繁殖にも影響？ ／長野
農工大 高田特任教授らの研究チームが約8年に及び観察で調べると、通説に反する両者の関係が見えてきたと、紹介される。
毎日新聞
自 2023年10月06日, 至 2023年10月06日 - 「ナニコレ珍百景」
民家近くでのカモシカの出現にカモシカの専門家・髙田先生のインタビューが放映される。
テレビ朝日
自 2023年10月01日, 至 2023年10月01日 - 【毎小ニュース】環境 「幻の動物」が街に 餌を取られて？
かつて「幻の動物」と言われ、国の特別天然記念物に指定されているニホンカモシカが市街地に姿を現すようになったことについて、高田先生のコメントが紹介される。
毎日新聞
自 2023年09月22日, 至 2023年09月22日 - カモシカ威嚇 シカはシカト 遭遇時の行動 東農工大調査
山でカモシカとシカが出合ったとき、どのような行動を取るのかを高田先生らの研究チームは約8年に及ぶ観察で調べると、通説に反する両者の関係が見えてきたと紹介される。
毎日新聞
自 2023年09月22日, 至 2023年09月22日 - 【くらしナビ―環境－】餌争奪に敗れ？「幻の動物」が市街地に
かつて「幻の動物」と言われ、国の特別天然記念物に指定されているニホンカモシカが市街地に姿を現すようになったことについて、高田先生のコメントが紹介される。
毎日新聞
自 2023年09月12日, 至 2023年09月12日 - 山で出合ったカモシカ 攻撃をしかけるのはどっち？
山でカモシカとシカが出合ったとき、どのような行動を取るのかを農工大・高田隼人特任准教授らの研究チームが約８年に及ぶ観察で調べると、通説に反する両者の関係が見えてきたと、紹介される。
毎日新聞
自 2023年09月10日, 至 2023年09月10日 - かつては「幻」今は悩みの種? カモシカはなぜ街に来るのか
かつて「幻の動物」と言われ、国の特別天然記念物に指定されているニホンカモシカが市街地に姿を現すようになった。3年余カモシカとシカの行動を観察した高田先生のコメントが紹介される。
毎日新聞
自 2023年09月10日, 至 2023年09月10日 - カモシカとシカ 出会ったら体小さいカモシカが攻撃 シカは平然
カモシカとシカが野山で遭遇すると、体が小さいカモシカの方が、体の大きいシカに対して攻撃な行動をとることが、研究チームの調査で分かったと、紹介される。
朝日新聞
自 2023年08月02日, 至 2023年08月02日 - シカがあらわれた！カモシカ「たたかう にげる ぼうぎょ」どれ？
カモシカとシカが野山で遭遇すると、体が小さいカモシカの方が、体の大きいシカに対して攻撃な行動をとることが、研究チームの調査で分かったと、紹介される。
朝日新聞DIGITAL
自 2023年08月02日, 至 2023年08月02日 - カモシカとシカ、出会ったら 体小さいカモシカが攻撃、シカは平然
カモシカとシカが野山で遭遇すると、体が小さいカモシカの方が、体の大きいシカに対して攻撃な行動をとることが、研究チームの調査で分かったと、紹介される。
朝日新聞DIGITAL
自 2023年08月02日, 至 2023年08月02日 - 継続観察で見えてきたシカとカモシカの関係性 農工大など
農工大らの研究グループは、シカとカモシカの直接的な交渉を8年間直接観察、シカからカモシカへの攻撃は観察されなかったのに対し、カモシカから鹿への攻撃は多数観察されたと発表したと紹介される。
NEWS SALT
自 2023年07月17日, 至 2023年07月17日 - 毎小ニュース 話題 富士山のカモシカ 移動距離トップ
国内のニホンカモシカの中で、富士山で生息するカモシカが最も長い距離を移動して餌を求めいていたことが、農工大の研究チームの調査結果で分かったと紹介される。
毎日新聞
自 2023年06月28日, 至 2023年06月28日 - 富士山カモシカ、足で稼ぎ餌探す 他地域の30倍
農工大高田特任准教授の研究チームは、富士山に生息するカモシカは、他の森林帯にいるカモシカより30倍も広い行動範囲だったという研究結果を得たと、紹介される。
毎日新聞
自 2023年06月27日, 至 2023年06月27日 - 餌が欲しけりゃ足で稼げ富士山生息のカモシカ農工大調査 他地域の30倍
農工大高田特任准教授の研究チームは、富士山に生息するカモシカは、他の森林帯にいるカモシカより30倍も広い行動範囲だったという研究結果を得たと、紹介される。
毎日新聞
自 2023年06月26日, 至 2023年06月26日 - 富士山のカモシカ、足で稼いで餌求める 他地域より30倍の行動範囲
国内のニホンカモシカの中で、富士山で生息するカモシカが最も足で餌を求めいていたことが農工大高田特任准教授の研究チームの調査結果で得られたと紹介される。
毎日新聞
自 2023年06月23日, 至 2023年06月23日 - 髙田先生の、富士山に生息するシカとカモシカの種間関係とその研究成果について掲載される。
子供の科学 2023年7月号
自 2023年06月10日, 至 2023年06月10日 - 東京農工大、シカとカモシカの食物をめぐる種間関係を解明
東京農工大学大学院農学府 修士課程学生 比留間光子、同大学農学部附属野生動物管理教育研究センターの高田隼人特任准教授、同大学院グローバルイノベーション研究院の小池伸介教授、山梨県富士山科学研究所研究部自然環境科鷲田茜らの共同研究チームは山梨県富士山麓の亜高山帯針葉樹林および高山帯火山荒原においてニホンジカとニホンカモシカを対象に糞分析による食性調査を実施し、2種の食物をめぐる種間関係を解明したと紹介される。
日本経済新聞
自 2023年04月11日, 至 2023年04月11日 - 富士山高山帯のニホンカモシカは行動圏も生息地選択の季節変化も大きい、東京農工大学
東京農工大学の髙田隼人特任准教授（当時、山梨県富士山科学研究所）は山梨県の富士山高山帯に生息するニホンカモシカの空間行動を調査し、森林に生息するカモシカと大きく異なる空間行動を持つことを世界で初めて明らかにしたと紹介される。
大学ジャーナル
自 2023年04月08日, 至 2023年04月08日 - フロンティア発 カモシカの社会進化、捉えた 餌が豊富な草原で「多妻」
山地に住む国の特別天然記念物「ニホンカモシカ」は、森林に生息するときには一夫一妻制の関係なのに対して、草原では一夫多妻の関係になることが分かったとの研究結果を、東京農工大などのグループが動物行動学の国際誌に発表したと紹介される。
東京新聞／WEB
自 2023年03月19日, 至 2023年03月19日 - 「バラいろダンディ」
長野県小諸市浅間山に生息するニホンカモシカの行動生態について取材を受ける。
TOKYO MX
自 2023年03月17日, 至 2023年03月17日 - カモシカは森林から草原に移ると開放感で「プレイボーイ」になる?
東京農工大学の研究チームは、7年にわたるニホンカモシカの長期観察から、森林に暮らすカモシカと草原に暮らすカモシカでは”恋愛事情”が変わることを発見したと紹介される。
ナゾロジー
自 2023年03月13日, 至 2023年03月13日 - さわやか自然百景「浅間山 秋」
長野県小諸市浅間山に生息するニホンカモシカの生態について
NHK総合
自 2022年12月18日, 至 2022年12月18日 - 雌もアピール！？カモシカの繁殖事情
農工大 髙田隼人特任准教授がニホンカモシカの調査をしたところ、ため糞が縄張りではなく雌が発情状態を知らせるためにつくられることが分かった、と掲載される。
National Geographic
自 2025年08月29日, 至 2025年08月29日 - 「ダーウィンが来た！」
特集「密着４０年！断崖絶壁でシロイワヤギを追え」で農工大 髙田隼人特任准教授が監修等を行う。
NHK
自 2025年07月06日, 至 2025年07月06日 - 「行くぜ！“地球の特等席”ロマンチック少年ボーイ」
農工大の高田隼人特任准教授提供の特別天然記念物ニホンカモシカの映像が放送される。
TBS
自 2025年06月24日, 至 2025年06月24日 - ためたウンチで発情期アピール？ メスのカモシカ、トイレ通じ伝達か
農工大ら研究チームは、ニホンカモシカのメスがオスにアピールするために「ウンチの山」（ため糞）を作っている可能性があるとの成果をまとめた、と掲載される。
withnews
自 2025年05月18日, 至 2025年05月18日 - 山梨・富士山北麓のニホンジカを調査、捕獲リスクへの行動に性差？
農工大らの調査で、山梨県の富士山北麓での人間の捕獲活動によって、ニホンジカがエサ場とするエリアがオスとメスで異なってきていることが分かった、と掲載される。
朝日新聞
自 2026年03月14日, 至 2026年03月14日 - 富士山麓 シカの居場所で性差 オスは捕獲リスクあっても餌重視 メスは繁殖第一で伐採地へ 富士山科学研・農工大が解明
農工大 高田隼人特任准教授と小池伸介教授らの共同研究チームが、富士山北鹿の広域でニホンジカの生息地利用の性差を解明したと発表した、と掲載される。
科学新聞
自 2026年03月06日, 至 2026年03月06日 - ニホンカモシカの「ため糞」はメスからオスへのアピール？東京農工大学・麻布大学
農工大らの研究チームは、ニホンカモシカのメスがふんや尿を特定の場所に集めるのは、異性に発情期をアピールしている可能性があると発表した、と掲載される。
大学ジャーナルオンライン
自 2025年05月07日, 至 2025年05月07日 - カモシカのメス、「トイレ」で発情期アピール？ 東京農工大学など
農工大らの研究チームは、ニホンカモシカのメスがふんや尿を特定の場所に集めるのは、異性に発情期をアピールしている可能性があると発表した、と掲載される。
日本経済新聞
自 2025年04月28日, 至 2025年04月28日 - ニホンカモシカ「トイレ」作る理由
農工大ら研究チームは、ニホンカモシカのメスがフンや尿を特定の場所に集まるのは、異性に発情期をアピールしている可能性があるとの成果をまとめた、と掲載される。
日本経済新聞
自 2025年05月13日, 至 2025年05月13日 - テングコウモリ 着地して虫捕食か
農工大は日本の森林に生息するテングコウモリの食性を明らかにした、と掲載される。
日本経済新聞
自 2026年02月01日, 至 2026年02月01日