Shigeru Suzuki | Ryukoku University (original) (raw)
Papers by Shigeru Suzuki
Primate Research, 1995
The purpose of the present survey was to investigate the awareness of the public on the problems ... more The purpose of the present survey was to investigate the awareness of the public on the problems arising from provisioning. The social problems of provisioned wild Japanese macaques happens throughout Japan including Yakushima Island in Kagoshima Prefecture. A questionnaire was given
Among wild Japanese macaques, male life history traits such as tenure in a troop and dominance ra... more Among wild Japanese macaques, male life history traits such as tenure in a troop and dominance rank structure tend to be similar between study populations irrespective of habitat differences. While males transfer throughout their lives alone and voluntarily, only prime adult males takeover an alpha rank when groups contain few males but most males immigrate into a group at very low rank. Male dominance hierarchy is stable during their tenure and males usually rise in rank as more dominant males emigrate or die. Most males in any rank eventually emigrate from a group with an average of 3 years of tenure and males at higher rank do not tend to stay longer in a group than subordinate males. As they mature, males get more chances of transferring into troops higher up in the male hierarchy, and their ranks basically tend to be associated with male age. Since these aspects of male life history should bring difficulties for adult males to immigrate into a troop with relatively large number...
Great Ape Societies, 1996
Primates; journal of primatology, 2003
We examined the relationship between fruit abundance and chimpanzee (Pan troglodytes) party size ... more We examined the relationship between fruit abundance and chimpanzee (Pan troglodytes) party size by comparing data from four study sites: the Kalinzu Forest Reserve, Uganda, the Djinji Camp and Guga Camp in the Ndoki Forest, Congo, and Kahuzi-Biega National Park, Democratic Republic of Congo. Although the difference in the fruit abundance between the sites was responsible for the difference in the party size between the sites, the seasonal changes in fruit abundance did not explain the changes in the party size in each study site. Across the four study sites, there were significant correlations of the mean and minimum of monthly party size with the mean of monthly fruiting-tree density, and a significant correlation of the maximum of monthly party sizes with the minimum of monthly fruiting-tree density. We proposed a hypothesis that (1) the monthly fruit abundance affects the monthly party size in the sites where the fruit availability is as low as to limit the party size during a m...
Primate Research, 1994
and Shigeru SUZUKI3) were used for the analyses. Macaques were found at all sites. The mean numbe... more and Shigeru SUZUKI3) were used for the analyses. Macaques were found at all sites. The mean number of groups seen or heard ranged from 0.11 to 0.82/km/day, and was positively correlated (rs=0.64) with the proportion of mature forest at each site. There was no clear correlation between the mean detection rate of groups and the rate at which droppings were found. The latter may be a less accurate measure of relative group density in a short-term survey. Although Yakushima macaques do utilise areas within 25 years of heavy logging, more groups were found in areas where logging was less recent and/or less extensive. A long-term survey is now underway which will assess the details of this relationship, the influence of forestry plantations, and seasonal variation in use of different habitat types.
Primates, 1996
... Chimpanzee Material Culture. Cambridge Univ. Press, Cambridge. MCGREW, WC; BALDWIN, PJ; TUTIN... more ... Chimpanzee Material Culture. Cambridge Univ. Press, Cambridge. MCGREW, WC; BALDWIN, PJ; TUTIN, CEG 1988. Diet of wild chimpanzees (Pan troglodytes verus) at Mt. Assirik, Senegal: I. Composition. Amer. J. Primatol., 16: 213-226. MITANI, M. 1990. ...
Primates, 1999
There is wide interest in the effects of reproductive biology, mating partner preference, and ran... more There is wide interest in the effects of reproductive biology, mating partner preference, and rank on mating success (MS) and reproductive success (RS) in primates. In particular, theory stresses importance on the mechanisms for attaining RS. Most theory hedges on competitive ability and priority of access to resources, whether they be food or estrous females. However, the majority of data used in favor of such hypotheses come from relatively short-term studies. We review these hypotheses based on longterm data from provisioned and unprovisioned populations of Japanese macaques. Neither MS nor RS were consistently attained by high-ranking males and females. For males, female choice and mating partner preference is seen to override most male-male competitive behaviors likely to affect MS and RS through priority of access to estrous females. Long-term mating patterns driven largely by female partner preferences, results in decreasing MS and RS for older higher-ranking males. The long-term trend for females to prefer less familiar or novel partners results in higher MS and RS for younger, middle-ranking males. The effects of this vary according to troop size and the duration of male tenure. For females, no consistent trend was recognized for rank related RS in either provisioned or unprovisioned troops. Nonreproductive mating may provide differential benefit to high-ranking females for access to limited food resources in some habitats but overall the relationship was inconclusive. Distribution and defendability of food resource, rather than provisioning per se may be more important.
Primates, 1995
The average time lag between the last parturition and the disappearance/death was 6.0 years for t... more The average time lag between the last parturition and the disappearance/death was 6.0 years for the Japanese macaque females that survived at least to the age of 20 years in the Arashiyama B troop. Since it may take 1.5 years for the last offspring to become able to survive without the mother, 4.5 years may correspond to the "post-reproductive life span (PRLS)," which occupied about 16% of the average span of their lives (27.3 years). During the PRLSs, the females continued to become estrous and mate with the males for at least several years. On the other hand, one of the oldest females showed neither estrus nor copulatory behaviors. There may be several causes for the lack of reproductive success among old aged females: (1) in spite of ovulation, other physiological functions related to conception may have declined; (2) the old aged females may not have been able to maintain pregnancy, and may have aborted; or (3) the old aged females may have exhibited estrus without ovulation, and may be considered to have been in menopause. In the Arashiyama B troop, PRLS may not be an unusual phenomenon, because, out of the 32 females born from 1954 to 1963, 13 females (41~ survived to the age of 20 yrs and most of them exhibited conspicuous PRLSs. Similar PRLSs were found in a non-provisioned population of the Japanese macaque of Yakushima Island, and in a wild population of the chimpanzee of the Mahale Mountains National Park, Tanzania.
American Journal of Primatology, 1994
A wild Japanese macaque troop decreased in size because the birth rate dropped and infant mortali... more A wild Japanese macaque troop decreased in size because the birth rate dropped and infant mortality increased. In the 1989 mating season, the last male left the troop, and the remaining two females joined a neighbor-ing troop. Thus, the troop ceased to exist as an ...
Tropics, 1994
Research on lowland gorillas (Gorilla g. gorilla) and chimpanzees (Pan t. troglodytes) began at t... more Research on lowland gorillas (Gorilla g. gorilla) and chimpanzees (Pan t. troglodytes) began at the 'Station d'Etudes des Gorilles et Chimpanzes' in the Lope Reserve, central Gabon, in 1983 and is ongoing. This paper lists 676 species of plants belonging to 91 families that occur in the 50 sq. km study area. Data on trees with diameters of 10 cm or more were collected systematically along line transects and opportunistic collections of fertile plants were made. For each plant species, the life-form, habitat preference and density (for trees recorded on transects) are listed. For plants that provide food for gorillas and chimpanzees, the part eaten is given. The plant species list is not complete but shows the flora of the SEGC study area to be diverse. The seven habitat types described range from Savanna to Closed Canopy Forest but the study area is dominated by Marantaceae Forest. Gorillas and chimpanzees at Lope have diverse diets and obtain food from plants in all of the habitat types. Some minor (in terms of area) habitats provide large amounts of food in particular seasons. Comparison of ape diets in different parts of Africa can only advance if vegetation inventories for each study site are compiled and published.
Primates, 1998
It is predicted that variation in intergroup relationships in group living primates reflects the ... more It is predicted that variation in intergroup relationships in group living primates reflects the cost and benefit of resource defense. We tested the applicability of the model by examining population difference, group difference, and seasonal difference in behaviors ...
Primates, 1998
It is predicted that variation in intergroup relationships in group living primates reflects the ... more It is predicted that variation in intergroup relationships in group living primates reflects the cost and benefit of resource defense. We tested the applicability of the model by examining population difference, group difference, and seasonal difference in behaviors ...
Primate Research, 1995
The purpose of the present survey was to investigate the awareness of the public on the problems ... more The purpose of the present survey was to investigate the awareness of the public on the problems arising from provisioning. The social problems of provisioned wild Japanese macaques happens throughout Japan including Yakushima Island in Kagoshima Prefecture. A questionnaire was given
Among wild Japanese macaques, male life history traits such as tenure in a troop and dominance ra... more Among wild Japanese macaques, male life history traits such as tenure in a troop and dominance rank structure tend to be similar between study populations irrespective of habitat differences. While males transfer throughout their lives alone and voluntarily, only prime adult males takeover an alpha rank when groups contain few males but most males immigrate into a group at very low rank. Male dominance hierarchy is stable during their tenure and males usually rise in rank as more dominant males emigrate or die. Most males in any rank eventually emigrate from a group with an average of 3 years of tenure and males at higher rank do not tend to stay longer in a group than subordinate males. As they mature, males get more chances of transferring into troops higher up in the male hierarchy, and their ranks basically tend to be associated with male age. Since these aspects of male life history should bring difficulties for adult males to immigrate into a troop with relatively large number...
Great Ape Societies, 1996
Primates; journal of primatology, 2003
We examined the relationship between fruit abundance and chimpanzee (Pan troglodytes) party size ... more We examined the relationship between fruit abundance and chimpanzee (Pan troglodytes) party size by comparing data from four study sites: the Kalinzu Forest Reserve, Uganda, the Djinji Camp and Guga Camp in the Ndoki Forest, Congo, and Kahuzi-Biega National Park, Democratic Republic of Congo. Although the difference in the fruit abundance between the sites was responsible for the difference in the party size between the sites, the seasonal changes in fruit abundance did not explain the changes in the party size in each study site. Across the four study sites, there were significant correlations of the mean and minimum of monthly party size with the mean of monthly fruiting-tree density, and a significant correlation of the maximum of monthly party sizes with the minimum of monthly fruiting-tree density. We proposed a hypothesis that (1) the monthly fruit abundance affects the monthly party size in the sites where the fruit availability is as low as to limit the party size during a m...
Primate Research, 1994
and Shigeru SUZUKI3) were used for the analyses. Macaques were found at all sites. The mean numbe... more and Shigeru SUZUKI3) were used for the analyses. Macaques were found at all sites. The mean number of groups seen or heard ranged from 0.11 to 0.82/km/day, and was positively correlated (rs=0.64) with the proportion of mature forest at each site. There was no clear correlation between the mean detection rate of groups and the rate at which droppings were found. The latter may be a less accurate measure of relative group density in a short-term survey. Although Yakushima macaques do utilise areas within 25 years of heavy logging, more groups were found in areas where logging was less recent and/or less extensive. A long-term survey is now underway which will assess the details of this relationship, the influence of forestry plantations, and seasonal variation in use of different habitat types.
Primates, 1996
... Chimpanzee Material Culture. Cambridge Univ. Press, Cambridge. MCGREW, WC; BALDWIN, PJ; TUTIN... more ... Chimpanzee Material Culture. Cambridge Univ. Press, Cambridge. MCGREW, WC; BALDWIN, PJ; TUTIN, CEG 1988. Diet of wild chimpanzees (Pan troglodytes verus) at Mt. Assirik, Senegal: I. Composition. Amer. J. Primatol., 16: 213-226. MITANI, M. 1990. ...
Primates, 1999
There is wide interest in the effects of reproductive biology, mating partner preference, and ran... more There is wide interest in the effects of reproductive biology, mating partner preference, and rank on mating success (MS) and reproductive success (RS) in primates. In particular, theory stresses importance on the mechanisms for attaining RS. Most theory hedges on competitive ability and priority of access to resources, whether they be food or estrous females. However, the majority of data used in favor of such hypotheses come from relatively short-term studies. We review these hypotheses based on longterm data from provisioned and unprovisioned populations of Japanese macaques. Neither MS nor RS were consistently attained by high-ranking males and females. For males, female choice and mating partner preference is seen to override most male-male competitive behaviors likely to affect MS and RS through priority of access to estrous females. Long-term mating patterns driven largely by female partner preferences, results in decreasing MS and RS for older higher-ranking males. The long-term trend for females to prefer less familiar or novel partners results in higher MS and RS for younger, middle-ranking males. The effects of this vary according to troop size and the duration of male tenure. For females, no consistent trend was recognized for rank related RS in either provisioned or unprovisioned troops. Nonreproductive mating may provide differential benefit to high-ranking females for access to limited food resources in some habitats but overall the relationship was inconclusive. Distribution and defendability of food resource, rather than provisioning per se may be more important.
Primates, 1995
The average time lag between the last parturition and the disappearance/death was 6.0 years for t... more The average time lag between the last parturition and the disappearance/death was 6.0 years for the Japanese macaque females that survived at least to the age of 20 years in the Arashiyama B troop. Since it may take 1.5 years for the last offspring to become able to survive without the mother, 4.5 years may correspond to the "post-reproductive life span (PRLS)," which occupied about 16% of the average span of their lives (27.3 years). During the PRLSs, the females continued to become estrous and mate with the males for at least several years. On the other hand, one of the oldest females showed neither estrus nor copulatory behaviors. There may be several causes for the lack of reproductive success among old aged females: (1) in spite of ovulation, other physiological functions related to conception may have declined; (2) the old aged females may not have been able to maintain pregnancy, and may have aborted; or (3) the old aged females may have exhibited estrus without ovulation, and may be considered to have been in menopause. In the Arashiyama B troop, PRLS may not be an unusual phenomenon, because, out of the 32 females born from 1954 to 1963, 13 females (41~ survived to the age of 20 yrs and most of them exhibited conspicuous PRLSs. Similar PRLSs were found in a non-provisioned population of the Japanese macaque of Yakushima Island, and in a wild population of the chimpanzee of the Mahale Mountains National Park, Tanzania.
American Journal of Primatology, 1994
A wild Japanese macaque troop decreased in size because the birth rate dropped and infant mortali... more A wild Japanese macaque troop decreased in size because the birth rate dropped and infant mortality increased. In the 1989 mating season, the last male left the troop, and the remaining two females joined a neighbor-ing troop. Thus, the troop ceased to exist as an ...
Tropics, 1994
Research on lowland gorillas (Gorilla g. gorilla) and chimpanzees (Pan t. troglodytes) began at t... more Research on lowland gorillas (Gorilla g. gorilla) and chimpanzees (Pan t. troglodytes) began at the 'Station d'Etudes des Gorilles et Chimpanzes' in the Lope Reserve, central Gabon, in 1983 and is ongoing. This paper lists 676 species of plants belonging to 91 families that occur in the 50 sq. km study area. Data on trees with diameters of 10 cm or more were collected systematically along line transects and opportunistic collections of fertile plants were made. For each plant species, the life-form, habitat preference and density (for trees recorded on transects) are listed. For plants that provide food for gorillas and chimpanzees, the part eaten is given. The plant species list is not complete but shows the flora of the SEGC study area to be diverse. The seven habitat types described range from Savanna to Closed Canopy Forest but the study area is dominated by Marantaceae Forest. Gorillas and chimpanzees at Lope have diverse diets and obtain food from plants in all of the habitat types. Some minor (in terms of area) habitats provide large amounts of food in particular seasons. Comparison of ape diets in different parts of Africa can only advance if vegetation inventories for each study site are compiled and published.
Primates, 1998
It is predicted that variation in intergroup relationships in group living primates reflects the ... more It is predicted that variation in intergroup relationships in group living primates reflects the cost and benefit of resource defense. We tested the applicability of the model by examining population difference, group difference, and seasonal difference in behaviors ...
Primates, 1998
It is predicted that variation in intergroup relationships in group living primates reflects the ... more It is predicted that variation in intergroup relationships in group living primates reflects the cost and benefit of resource defense. We tested the applicability of the model by examining population difference, group difference, and seasonal difference in behaviors ...