111 research outputs found

    Observation of an adult female oribi with leucistic pelage in Lobo, Serengeti National Park, Tanzania

    Get PDF
    The oribi (Bovidae: Antilopinae: Ourebiini: Ourebia ourebi [Zimmermann, 1783 ]) is a small antelope distributed widely across open woody grasslands of sub‐Saharan Africa (Goldspink, Holland, Sweet, & Stewart, 2002 ), especially in hilly open‐broadleaf savanna and primarily feeds on herbaceous vegetation (Monfort & Monfort, 1974 ). The species lives singly or in small groups with multiple males, yet long‐term pairing is frequently low (Adamczak & Dunbar, 2008 ; Arcese, 1994 ; Arcese, Jongejan, & Sinclair, 1995 ; Jongejan, Arcese, & Sinclair, 1991 ). Oribi are readily identifiable with a tan coat and whitish underbelly, large ears, a conspicuous black‐coloured preorbital glandular spot below the ear, long neck and long legs (Foley et al., 2014 ; Kingdon et al., 2013 ). Up to 13 subspecies have been described with one subspecies found in Serengeti National Park: O. ourebi cottoni

    Stabilizing effects of group formation by Serengeti herbivores on predator-prey dynamics

    Get PDF
    Predator-prey theory often assumes that potential prey individuals are solitary and evenly distributed in space. This assumption is violated in social, mobile prey, such as many ungulates. Here we use data from 80 monthly field censuses to estimate the parameters for a power relationship between herd density and population density for eight species of large herbivores commonly found in the diet of Serengeti lions, confirming a power relationship proposed from a preliminary Serengeti dataset. Here we extend our analysis of that model to demonstrate how parameters of the power function relate to average herd size and density-dependent changes in herd size and evaluate how interspecific variation in these parameters shapes the group-dependent functional response by Serengeti lions for eight prey species. We apply the different prey-specific functional response models in a Rosenzweig-MacArthur framework to compare their impact on the stability of predator–prey dynamics. Model outcomes suggest that group formation plays a strong role in stabilizing lion–herbivore interactions in Serengeti by forcing lions to search over a larger area before each prey encounter. As a consequence of grouping by their prey, our model also suggests that Serengeti lions are forced to broaden their diets to include multiple species of prey in order to persist, potentially explaining the generalist foraging by lions routinely recorded across multiple ecosystems

    A Novel Approach to Assessing the Prevalence and Drivers of Illegal Bushmeat Hunting in the Serengeti

    Get PDF
    Assessing anthropogenic effects on biological diversity, identifying drivers of human behavior, and motivating behavioral change are at the core of effective conservation. Yet knowledge of people's behaviors is often limited because the true extent of natural resource exploitation is difficult to ascertain, particularly if it is illegal. To obtain estimates of rule-breaking behavior, a technique has been developed with which to ask sensitive questions. We used this technique, unmatched-count technique (UCT), to provide estimates of bushmeat poaching, to determine motivation and seasonal and spatial distribution of poaching, and to characterize poaching households in the Serengeti. We also assessed the potential for survey biases on the basis of respondent perceptions of understanding, anonymity, and discomfort. Eighteen percent of households admitted to being involved in hunting. Illegal bushmeat hunting was more likely in households with seasonal or full-time employment, lower household size, and longer household residence in the village. The majority of respondents found the UCT questions easy to understand and were comfortable answering them. Our results suggest poaching remains widespread in the Serengeti and current alternative sources of income may not be sufficiently attractive to compete with the opportunities provided by hunting. We demonstrate that the UCT is well suited to investigating noncompliance in conservation because it reduces evasive responses, resulting in more accurate estimates, and is technically simple to apply. We suggest that the UCT could be more widely used, with the trade-off being the increased complexity of data analyses and requirement for large sample sizes

    Metabolic maturation in the first 2 years of life in resource-constrained settings and its association with postnatal growths

    Get PDF
    Funding Information: The Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project (MAL-ED) is carried out as a collaborative project supported by the Bill & Melinda Gates Foundation (BMGF 47075), the Foundation for the National Institutes of Health, and the National Institutes of Health, Fogarty International Center, while additional support was obtained from BMGF for the examination of host innate factors on enteric disease risk and enteropathy (grants OPP1066146 and OPP1152146 to M.N.K.). Additional funding was obtained from the Sherrilyn and Ken Fisher Center for Environmental Infectious Diseases of the Johns Hopkins School of Medicine (to M.N.K.). Publisher Copyright: Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).Peer reviewedPublisher PD

    Full breastfeeding protection against common enteric bacteria and viruses: Results from the MAL-ED cohort study

    Get PDF
    Background: Breastfeeding is known to reduce risk of enteropathogen infections, but protection from specific enteropathogens is not well characterized.Objective: To estimate the association between full breastfeeding (days fed breast milk exclusively or with non-nutritive liquids) and enteropathogen detection.Design: 2,145 newborns were enrolled in eight sites, of whom 1,712 had breastfeeding and key enteropathogen data through 6 months. We focused on eleven enteropathogens: adenovirus 40/41, norovirus, sapovirus, astrovirus, and rotavirus, enterotoxigenic Escherichia coli (ETEC), Campylobacter spp, and typical enteropathogenic E. coli as well as entero-aggregative E. coli, Shigella and Cryptosporidium. Logistic regression was used to estimate the risk of enteropathogen detection in stools and survival analysis to estimate the timing of first detection of an enteropathogen.Results: Infants with 10% more days of full breastfeeding within the preceding 30 days of a stool sample were less likely to have the three E. Coli and Campylobacter spp detected in their stool (mean odds 0.92-0.99) but equally likely (0.99-1.02) to have the viral pathogens detected in their stool. A 10% longer period of full breastfeeding from birth was associated with later first detection of the three E. Coli, Campylobacter, adenovirus, astrovirus, and rotavirus (mean hazard ratios of 0.52-0.75). The hazards declined and point estimates were not statistically significant at 3 months.Conclusions: In this large multi-center cohort study, full breastfeeding was associated with lower likelihood of detecting four important enteric pathogens in the first six months of life. These results also show that full breastfeeding is related to delays in the first detection of some bacterial and viral pathogens in the stool. As several of these pathogens are risk factors for poor growth during childhood, this work underscores the importance of exclusive or full breastfeeding during the first six months of life to optimize early health

    Influences on catch-up growth using relative versus absolute metrics : evidence from the MAL-ED cohort study

    Get PDF
    Acknowledgements The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project (MAL-ED) was a collaborative project led by the Foundation for the National Institutes of Health and the National Institutes of Health, Fogarty International Center. The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the U.S. National Institutes of Health or Department of Health and Human Services. Funding The MAL-ED study was supported by the Bill & Melinda Gates Foundation, through grants to the Foundation for the National Institutes of Health, and with additional support from the National Institutes of Health, Fogarty Inter- national Center. The funder had no direct role in the writing of the manu- script or in the study design, data collection, analysis or interpretation of study results. We are grateful to the children and caregivers who participated in the study for their invaluable contributions.Peer reviewedPublisher PD

    Enteric dysfunction and other factors associated with attained size at 5 years : MAL-ED birth cohort study findings

    Get PDF
    Funding Information: The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project (MAL-ED) is carried out as a collaborative project supported by the Bill & Melinda Gates Foundation, the Foundation for the NIH, and the NIH/Fogarty International Center. This work was also supported by the Fogarty International Center, NIH (D43-TW009359 to ETR).Peer reviewe
    • 

    corecore