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Human Presence (human + presence)
Selected AbstractsScale dependence of the correlation between human population presence and vertebrate and plant species richnessECOLOGY LETTERS, Issue 1 2007Marco Pautasso Abstract Human presence is generally negatively related to species richness locally, but the relationship is positive at coarse scales. An increase in the strength of the latter correlation with increasing study resolution has been documented within studies, but it is not known whether such a scale dependence is present across different studies. We test this with data on the spatial co-occurrence of human beings and the species richness of plants and vertebrates from a continuum of scales. The correlation coefficient between human presence and species richness is positively related to study grain and extent. The correlation turns from positive to negative below a study grain of c. 1 km and below a study extent of c. 10 000 km2. The broad-scale positive correlation between human presence and species richness suggests that people have preferentially settled and generally flourished in areas of high biodiversity and/or have contributed to it with species introductions and habitat diversification. The scale dependency of the correlation between people and biodiversity's presence emphasizes the importance of the preservation of green areas in densely populated regions. [source] Behavioral responses of one western lowland gorilla (Gorilla gorilla gorilla) group at Bai Hokou, Central African Republic, to tourists, researchers and trackersAMERICAN JOURNAL OF PRIMATOLOGY, Issue 10 2010Michelle Klailova Abstract Gorilla tourism, widely perceived as a lucrative industry, is propelled by strong market demand with programs in five countries and for three of four gorilla subspecies. Human presence may negatively affect wild gorillas, potentially lowering immunity and increasing the likelihood of acquiring human-borne disease. Yet, behavioral impacts of humans on wild gorilla behavior remain largely unexplored, particularly for western lowland gorillas. We evaluate the impact of tourist presence, human observer numbers (tourists, trackers, and researchers), and human observer distance on the behavior of one habituated gorilla group at Bai Hokou, Central African Republic. Behavioral data were collected for more than 12 months from January 2007. Of silverback aggressive events, 39% (N=229) were human directed, but 65% were low-level soft barks. Adult females, and one in particular, were responsible for the highest number of aggressive events toward humans. Humans maintained closer proximity to the silverback when tourists were present, although tourist numbers had no significant impact on overall group activity budgets or rates of human-directed aggression. However, as research team size increased, group feeding rates decreased. Close observer,silverback distance correlated with a decrease in his feeding rates and an increase in human monitoring. He directed less aggression toward observers at distances >10,m, although observers spent 48.5% of time between 6 and 10,m of the silverback. We discuss gorilla personality as a factor in human-directed aggression. We explore whether the current 7,m distance limit governing gorilla tourism, based on disease transmission risks, is sufficient considering the potential behavioral stressor of close human presence. We recommend increasing minimum observation distance to >10,m where possible, decreasing observer group sizes, particularly after a visit consisting of maximum numbers and restricting tourist access to 1 visit/day. Am. J. Primatol. 72:897,906, 2010. © 2010 Wiley-Liss, Inc. [source] Temporal association between food distribution and human caregiver presence and the development of affinity to humans in lambsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2008Céline Tallet Abstract The presence of the caregiver around feeding favors the development of a human,animal relationship. To understand the underlying mechanism, we tested various temporal associations between food distribution and human presence: from an early age, a person was repeatedly present for 2 min just before milk distribution ("Forward"), during milk distribution ("Simultaneous"), and 20 min afterwards ("Delayed"). The "Control" group received no human contacts. During the treatments, "Forward" and "Delayed" lambs had more physical contacts with the person than "Simultaneous" lambs. When tested in unfamiliar environments, they stood longer near the person than did "Control" or "Simultaneous" lambs, which did not differ. Only "Forward" and "Delayed" lambs bleated when separated from the person. Fasting before testing had no effect. "Forward" and "Delayed" seemed to produce the same human,animal relationship, showing that this did not rely only on a conditioning process associating the caregiver with food. The caregiver may acquire properties for social support through other mechanisms (attachment and/or postingestive effects). © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 147,159, 2008. [source] Responses of weaned lambs to fear-eliciting situations: Origin of individual differencesDEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2003Manon Viérin Abstract The aims of this study were 1) to develop methods of objectively measuring fear in weaned lambs, and 2) to evaluate the effects of age, sex, breed, and rearing conditions on fear reactions. Four hundred forty-one lambs, aged 3 to 6 months, were submitted to three fear-eliciting situations (isolation, surprise effect, and human presence). Factor analysis revealed a first factor, interpreted in terms of fear, that accounted for 40% of total variance in the three tests. As in adult sheep, the main signs of fear were inhibition of feeding, long distance from the frightening stimulus, frequent immobilizations, and numerous high-pitch bleats. Behavior was also influenced by differences in general locomotor activity and exploratory motivation. Fear reactions were influenced by age (3- to 4-month-old lambs more fearful than 5- to 6-month-old), sex (females more fearful than males), breed (Romanov more fearful than Ile-de-France), and rearing conditions (artificial vs. maternal: almost no influence in males and influence in females depending on age). These results with sheep provide interesting theoretical and practical perspectives to the study of fearfulness. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 131,147, 2003 [source] Scale dependence of the correlation between human population presence and vertebrate and plant species richnessECOLOGY LETTERS, Issue 1 2007Marco Pautasso Abstract Human presence is generally negatively related to species richness locally, but the relationship is positive at coarse scales. An increase in the strength of the latter correlation with increasing study resolution has been documented within studies, but it is not known whether such a scale dependence is present across different studies. We test this with data on the spatial co-occurrence of human beings and the species richness of plants and vertebrates from a continuum of scales. The correlation coefficient between human presence and species richness is positively related to study grain and extent. The correlation turns from positive to negative below a study grain of c. 1 km and below a study extent of c. 10 000 km2. The broad-scale positive correlation between human presence and species richness suggests that people have preferentially settled and generally flourished in areas of high biodiversity and/or have contributed to it with species introductions and habitat diversification. The scale dependency of the correlation between people and biodiversity's presence emphasizes the importance of the preservation of green areas in densely populated regions. [source] Evidence for indigenous selection and distribution of the shea tree, Vitellaria paradoxa, and its potential significance to prevailing parkland savanna tree patterns in sub-Saharan Africa north of the equatorJOURNAL OF BIOGEOGRAPHY, Issue 10 2003S. Maranz Abstract Aim, Woody vegetation patterns in African savannas north of the equator are closely connected to human presence, but the distinctions between natural and anthropogenic landscapes have not been clear to many observers. Criteria for identifying savanna landscapes on a continuum of intensity of anthropic impact are explored. Methods, A key savanna tree species, Vitellaria paradoxa (Sapotaceae), was used as model for evaluating anthropic impact. Fruits harvested from tree populations across the species range were analysed for variation in traits valued by indigenous peoples. A simple selection index was used to scale tree populations from a hypothetical wild state to a hypothetical domesticated state. Index values were compared with trait values along climate zone gradients and evaluated in the context of indigenous savanna management practices and historical species distribution reports. Results, Trait values such as fruit size and shape, pulp sweetness, and kernel fat content show a significant influence of temperature and rainfall. At the same time, the mean values of groups of traits vary perpendicular to the general climatic zone gradient. Selection index values between Vitellaria populations vary up to sixfold, with highest values in central Burkina Faso. Comparison of present day Vitellaria distribution with historical range limits show range expansion by human migration. Main conclusions, The prevalence of major economic tree species in the savannas of Africa north of the equator is a strong indicator of human involvement in tree dispersal. This conclusion is supported by paleobotanical evidence and by recent Vitellaria range expansion as a result of human migration. The presence of high mean values of several Vitellaria fruit traits in central Burkina Faso suggests that selection for desired characteristics has occurred. The impact of indigenous savanna peoples on woody species composition and spatial distribution is probably much greater than usually thought and is the result of a deliberate strategy of altering the landscape to provide needed human resources. [source] Bacterial ancient DNA as an indicator of human presence in the past: its correlation with palynological and archaeological data,JOURNAL OF QUATERNARY SCIENCE, Issue 4 2009Jacek Madeja Abstract Palynological investigation is one of the most important tools for reconstructing past vegetation. Some plants have proved to be relatively sensitive indicators of human activity, but most of them are not specific. In this paper we propose a method which can be used for the verification of phases of anthropogenic impact on vegetation distinguished in pollen diagrams. In this work we adopted the existing molecular methods for tracking bacterial ancient DNA of Bifidobacterium and Bacteroides-Prevotella (known as human- and cow-specific genetic markers) in palynologically and archaeologically associated sediments. This method can be helpful in determining local human presence, especially in those time periods when pollen analysis has not always been very discriminating (Palaeolithic, Mesolithic) and at sites without archaeological evidence. Copyright © 2008 John Wiley & Sons, Ltd. [source] The human colonisation of Europe: where are we?,,JOURNAL OF QUATERNARY SCIENCE, Issue 5 2006Wil Roebroeks Abstract This paper focuses on the earlier parts of the human colonisation of Europe and its wider setting and addresses the two basic tasks of archaeologists working in this field: (1) to identify the spatio-temporal patterns of human presence and absence, i.e. getting the pattern ,right'; (2) to explain these patterns. Archaeologists have invested mostly in the first task, while the second one takes us to the field of biogeography. Study of biogeographical limits of hominins necessitates integration of many aspects of a species, e.g. diet, life history and social organisation, and the way environmental factors shape these. Palaeoanthropologists need to combine these with establishing data on the chronology of hominin presence, on palaeoenvironment and climatic oscillations, on emergence and disappearance of land bridges, and so on. They further have to acknowledge the fact that only very small parts of the former ranges of the species have been sampled ,adequately'. The paper explores some of the key issues at stake in dealing with the human colonisation of Europe. Copyright © 2006 John Wiley & Sons, Ltd. [source] Behavioral responses of one western lowland gorilla (Gorilla gorilla gorilla) group at Bai Hokou, Central African Republic, to tourists, researchers and trackersAMERICAN JOURNAL OF PRIMATOLOGY, Issue 10 2010Michelle Klailova Abstract Gorilla tourism, widely perceived as a lucrative industry, is propelled by strong market demand with programs in five countries and for three of four gorilla subspecies. Human presence may negatively affect wild gorillas, potentially lowering immunity and increasing the likelihood of acquiring human-borne disease. Yet, behavioral impacts of humans on wild gorilla behavior remain largely unexplored, particularly for western lowland gorillas. We evaluate the impact of tourist presence, human observer numbers (tourists, trackers, and researchers), and human observer distance on the behavior of one habituated gorilla group at Bai Hokou, Central African Republic. Behavioral data were collected for more than 12 months from January 2007. Of silverback aggressive events, 39% (N=229) were human directed, but 65% were low-level soft barks. Adult females, and one in particular, were responsible for the highest number of aggressive events toward humans. Humans maintained closer proximity to the silverback when tourists were present, although tourist numbers had no significant impact on overall group activity budgets or rates of human-directed aggression. However, as research team size increased, group feeding rates decreased. Close observer,silverback distance correlated with a decrease in his feeding rates and an increase in human monitoring. He directed less aggression toward observers at distances >10,m, although observers spent 48.5% of time between 6 and 10,m of the silverback. We discuss gorilla personality as a factor in human-directed aggression. We explore whether the current 7,m distance limit governing gorilla tourism, based on disease transmission risks, is sufficient considering the potential behavioral stressor of close human presence. We recommend increasing minimum observation distance to >10,m where possible, decreasing observer group sizes, particularly after a visit consisting of maximum numbers and restricting tourist access to 1 visit/day. Am. J. Primatol. 72:897,906, 2010. © 2010 Wiley-Liss, Inc. [source] Ethical issues faced by field primatologists: asking the relevant questionsAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2010Linda Marie Fedigan Abstract Field primatologists face unusual ethical issues. We study animals rather than people and receive research approval from animal care rather than ethics committees. However, animal care evaluation forms are developed from concerns about laboratory animal research and are based on the "Three R's" for humane treatment of captive experimental subjects (replacement, reduction and refinement), which are only debatably relevant to field research. Scientists who study wild, free-ranging primates in host countries experience many ethical dilemmas seldom dealt with in animal care forms. This paper reviews the ethical issues many field primatologists say they face and how these might be better addressed by animal care forms. The ethical issues arising for field researchers are divided into three categories: "Presence, Protocols and People" and for each the most frequent issues are described. The most commonly mentioned ethical concern arising from our presence in the field is the possibility of disease transmission. Although most primate field studies employ only observational protocols, the practice of habituating our study animals to close human presence is an ethical concern for many since it can lessen the animals' fear of all humans, thereby facilitating undesirable behaviors (e.g., crop-raiding) and rendering them vulnerable to harm. Field primatologists who work in host countries must observe national laws and local traditions. As conservationists, primatologists must often negotiate between the resource needs and cultural practices of local people and the interests of the nonhuman primates. Many say they face more ethical dilemmas arising from human interactions than from research on the animals per se. This review concludes with suggestions for relevant questions to ask on animal care forms, and actions that field primatologists can take to better inform animal care committees about the common ethical issues we experience as well as how to develop guidelines for addressing them. Am. J. Primatol. 72:754,771, 2010. © 2010 Wiley-Liss, Inc. [source] The influence of human disturbance on California sea lions during the breeding seasonANIMAL CONSERVATION, Issue 6 2009K. Holcomb Abstract California sea lions Zalophus californianus occupy 26 islands in the Gulf of California (GoC), Mexico. Although human presence is prohibited on these islands without a government permit, the law is not enforced and tourism to the islands is increasing. Tourists, along with local fishermen, often come ashore to get close to the animals, which may disrupt behaviors critical for reproduction. In this paper, we report the results of an experimental study on the behavioral effects of human disturbance on California sea lions in the GoC. To document effects, we recorded sea lion behavior immediately before and in 10-min intervals for up to an hour after experimental human disturbance. Our results showed few behavioral responses of sea lions to human disturbance. Adult females and juveniles demonstrated immediate responses, but these were not consistent between years, apparent an hour after disturbance, or evident across other age and sex classes. These results suggest that California sea lions may be resilient to human disturbance and a possible flagship species for ecotourism, but further studies of the physiological and population-level effects of human disturbance are needed. [source] | |||||||||||||