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Higino GT, Banville F, Dansereau G, Forero Muñoz NR, Windsor F, Poisot T. Mismatch between IUCN range maps and species interactions data illustrated using the Serengeti food web. PeerJ 2023; 11:e14620. [PMID: 36793892 PMCID: PMC9924135 DOI: 10.7717/peerj.14620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 12/01/2022] [Indexed: 02/12/2023] Open
Abstract
Background Range maps are a useful tool to describe the spatial distribution of species. However, they need to be used with caution, as they essentially represent a rough approximation of a species' suitable habitats. When stacked together, the resulting communities in each grid cell may not always be realistic, especially when species interactions are taken into account. Here we show the extent of the mismatch between range maps, provided by the International Union for Conservation of Nature (IUCN), and species interactions data. More precisely, we show that local networks built from those stacked range maps often yield unrealistic communities, where species of higher trophic levels are completely disconnected from primary producers. Methodology We used the well-described Serengeti food web of mammals and plants as our case study, and identify areas of data mismatch within predators' range maps by taking into account food web structure. We then used occurrence data from the Global Biodiversity Information Facility (GBIF) to investigate where data is most lacking. Results We found that most predator ranges comprised large areas without any overlapping distribution of their prey. However, many of these areas contained GBIF occurrences of the predator. Conclusions Our results suggest that the mismatch between both data sources could be due either to the lack of information about ecological interactions or the geographical occurrence of prey. We finally discuss general guidelines to help identify defective data among distributions and interactions data, and we recommend this method as a valuable way to assess whether the occurrence data that are being used, even if incomplete, are ecologically accurate.
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Affiliation(s)
- Gracielle T. Higino
- Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Francis Banville
- University of Sherbrooke, Sherbrooke, Québec, Canada,University of Montreal, Montréal, Québec, Canada,Quebec Centre for Biodiversity Science, Montréal, Québec, Canada
| | - Gabriel Dansereau
- University of Montreal, Montréal, Québec, Canada,Quebec Centre for Biodiversity Science, Montréal, Québec, Canada
| | - Norma Rocio Forero Muñoz
- University of Montreal, Montréal, Québec, Canada,Quebec Centre for Biodiversity Science, Montréal, Québec, Canada
| | - Fredric Windsor
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Timothée Poisot
- University of Montreal, Montréal, Québec, Canada,Quebec Centre for Biodiversity Science, Montréal, Québec, Canada
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2
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Peral C, Landman M, Kerley GIH. The inappropriate use of time-to-independence biases estimates of activity patterns of free-ranging mammals derived from camera traps. Ecol Evol 2022; 12:e9408. [PMID: 36311406 PMCID: PMC9596328 DOI: 10.1002/ece3.9408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/15/2022] [Accepted: 09/21/2022] [Indexed: 11/16/2022] Open
Abstract
Measuring and comparing activity patterns provide key insights into the behavioral trade‐offs that result in animal activity and their extrinsic and intrinsic drivers. Camera traps are a recently emerged source of data for sampling animal activity used to estimate activity patterns. However, nearly 70% of studies using such data to estimate activity patterns apply a time‐to‐independence data filter to discard appreciable periods of sampling effort. This treatment of activity as a discrete event emerged from the use of camera trap data to estimate animal abundances, but does not reflect the continuous nature of behavior, and may bias resulting estimates of activity patterns. We used a large, freely available camera trap dataset to test the effects of time to independence on the estimated activity of eight medium‐ to large‐sized African mammals. We show that discarding data through the use of time‐to‐independence filters causes substantial losses in sample sizes and differences in the estimated activity of species. Activity patterns estimated for herbivore species were more affected by the application of time‐to‐independence data filters than carnivores, this extending to estimates of potential interactions (activity overlap) between herbivore species. We hypothesize that this pattern could reflect the typically more abundant, social, and patch‐specific foraging patterns of herbivores and suggest that this effect may bias estimates of predator–prey interactions. Activity estimates of rare species, with less data available, may be particularly vulnerable to loss of data through the application of time‐to‐independence data filters. We conclude that the application of time‐to‐independence data filters in camera trap‐based estimates of activity patterns is not valid and should not be used. A rapidly growing body of literature is using data from camera traps to describe and compare activity patterns in animals, but most such studies arbitrarily apply an inappropriate data filter of removing activity records for a time after each sample used, the so‐called time to independence. Using data for eight African large mammals, we show that this approach is not conceptually valid and leads to biases in the estimated activity patterns and that tests for interactions (overlap) using such estimates may not be useful.
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Affiliation(s)
- Christopher Peral
- Centre for African Conservation EcologyNelson Mandela UniversityGqeberhaSouth Africa
| | - Marietjie Landman
- Centre for African Conservation EcologyNelson Mandela UniversityGqeberhaSouth Africa
| | - Graham I. H. Kerley
- Centre for African Conservation EcologyNelson Mandela UniversityGqeberhaSouth Africa
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3
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Cory ST, Smith WK, Anderson TM. First-year Acacia seedlings are anisohydric "water-spenders" but differ in their rates of water use. Am J Bot 2022; 109:1251-1261. [PMID: 35791878 PMCID: PMC9544296 DOI: 10.1002/ajb2.16032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 06/06/2022] [Accepted: 06/08/2022] [Indexed: 06/15/2023]
Abstract
PREMISE First-year seedlings (FYS) of tree species may be a critical demographic bottleneck in semi-arid, seasonally dry ecosystems such as savannas. Given the highly variable water availability and potentially strong FYS-grass competition for water, FYS water-use strategies may play a crucial role in FYS establishment in savannas and, ultimately, in tree-grass competition and coexistence. METHODS We examined drought responses in FYS of two tree species that are dominant on opposite ends of an aridity gradient in Serengeti, Acacia (=Vachellia) tortilis and A. robusta. In a glasshouse experiment, gas exchange and whole-plant hydraulic conductance (Kplant ) were measured as soil water potential (Ψsoil ) declined. Trajectory of the Ψleaf /Ψsoil relationship during drought elucidated the degree of iso/anisohydry. RESULTS Both species were strongly anisohydric "water-spenders," allowing rapid wet-season C gain after pulses of moisture availability. Despite being equally vulnerable to declines in Kplant under severe drought, they differed in their rates of water use. Acacia tortilis, which occurs in the more arid regions, initially had greater Kmax , transpiration (E), and photosynthesis (Anet ) than A. robusta. CONCLUSIONS This work demonstrates an important mechanism of FYS establishment in savannas: Rather than investing in drought tolerance, savanna FYS maximize gas exchange during wet periods at the expense of desiccation during dry seasons. FYS establishment appears dependent on high C uptake during the pulses of water availability that characterize habitats dominated by these species. This study increases our understanding of species-scale plant ecophysiology and ecosystem-scale patterns of tree-grass coexistence.
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Affiliation(s)
- Scott T. Cory
- Department of BiologyWake Forest University1834 Wake Forest RoadWinston‐SalemNC27106USA
| | - William K. Smith
- Department of BiologyWake Forest University1834 Wake Forest RoadWinston‐SalemNC27106USA
| | - T. Michael Anderson
- Department of BiologyWake Forest University1834 Wake Forest RoadWinston‐SalemNC27106USA
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4
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de Jong YA, Butynski TM. Is the southern patas monkey Erythrocebus baumstarki Africa's next primate extinction? Reassessing taxonomy, distribution, abundance, and conservation. Am J Primatol 2021; 83:e23316. [PMID: 34473367 DOI: 10.1002/ajp.23316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 07/15/2021] [Accepted: 07/24/2021] [Indexed: 11/10/2022]
Abstract
The "Critically Endangered" southern patas monkey Erythrocebus baumstarki, thought to be endemic to Tanzania, has been resurrected to species level based on its geographic isolation, and on the coloration and pattern of its pelage. This study presents the first evidence for E. baumstarki in Kenya and reviews its historic and current geographic distributions based on the literature, museum specimens, online platforms, responses to requests for site records, and our own fieldwork. The distribution of E. baumstarki in the early 20th century was roughly 66,000 km2 . This has declined about 85% to around 9700 km2 at present (post-2009). The current "Extent of Occurrence" is only about 2150 km2 . This species was extirpated from Kenya in about 2015 and from the Kilimanjaro Region in Tanzania in about 2011. At present, E. baumstarki appears to be restricted to the protected areas of the western Serengeti, with the western Serengeti National Park being the stronghold. The number of individuals remaining is probably between 100 and 200, including between 50 and 100 mature individuals. The ultimate threat to E. baumstarki is the very rapidly increasing human population, while the main proximate threats are the degradation, loss, and fragmentation of natural habitats, and the related competition with people and livestock for habitat and water, particularly during droughts. Other problems are hunting by poachers and domestic dogs, and probably loss of genetic variation and climate change. This article provides recommendations for reducing the threats and promoting the recovery of E. baumstarki. We hope this article heightens awareness of the dire conservation status of E. baumstarki and encourages an increase in research and conservation action for this monkey.
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Affiliation(s)
- Yvonne A de Jong
- Eastern Africa Primate Diversity and Conservation Program, Nanyuki, Kenya
| | - Thomas M Butynski
- Eastern Africa Primate Diversity and Conservation Program, Nanyuki, Kenya
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5
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Ritchie ME, Penner JF. Episodic herbivory, plant density dependence, and stimulation of aboveground plant production. Ecol Evol 2020; 10:5302-5314. [PMID: 32607153 PMCID: PMC7319133 DOI: 10.1002/ece3.6274] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 01/16/2020] [Accepted: 03/09/2020] [Indexed: 11/19/2022] Open
Abstract
Herbivory is a major energy transfer within ecosystems; an open question is under what circumstances it can stimulate aboveground seasonal primary production. Despite multiple field demonstrations, past theory considered herbivory as a continuous process and found stimulation of seasonal production to be unlikely. Here, we report a new theoretical model that explores the consequences of discrete herbivory events, or episodes, separated in time. We discovered that negative density (biomass) dependence of plant growth, such as might be expected from resource limitation of plant growth, favors stimulation of seasonal production by infrequent herbivory events under a wide range of herbivory intensities and maximum plant relative growth rates. Results converge to those of previous models under repeated, short-interval herbivory, which generally reduces seasonal production. Model parameters were estimated with new and previous data from the Serengeti ecosystem. Patterns of observed frequent and large magnitude stimulated production in these data agreed generally with those predicted by the episodic herbivory model. The model thus may provide a new framework for evaluating the sustainability and impact of herbivory.
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6
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Weckworth JK, Davis BW, Dubovi E, Fountain-Jones N, Packer C, Cleaveland S, Craft ME, Eblate E, Schwartz M, Mills LS, Roelke-Parker M. Cross-species transmission and evolutionary dynamics of canine distemper virus during a spillover in African lions of Serengeti National Park. Mol Ecol 2020; 29:4308-4321. [PMID: 32306443 DOI: 10.1111/mec.15449] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 03/05/2020] [Accepted: 04/08/2020] [Indexed: 01/01/2023]
Abstract
The outcome of pathogen spillover from a reservoir to a novel host population can range from a "dead-end" when there is no onward transmission in the recipient population, to epidemic spread and even establishment in new hosts. Understanding the evolutionary epidemiology of spillover events leading to discrete outcomes in novel hosts is key to predicting risk and can lead to a better understanding of the mechanisms of emergence. Here we use a Bayesian phylodynamic approach to examine cross-species transmission and evolutionary dynamics during a canine distemper virus (CDV) spillover event causing clinical disease and population decline in an African lion population (Panthera leo) in the Serengeti Ecological Region between 1993 and 1994. Using 21 near-complete viral genomes from four species we found that this large-scale outbreak was likely ignited by a single cross-species spillover event from a canid reservoir to noncanid hosts <1 year before disease detection and explosive spread of CDV in lions. Cross-species transmission from other noncanid species probably fuelled the high prevalence of CDV across spatially structured lion prides. Multiple lines of evidence suggest that spotted hyenas (Crocuta crocuta) could have acted as the proximate source of CDV exposure in lions. We report 13 nucleotide substitutions segregating CDV strains found in canids and noncanids. Our results are consistent with the hypothesis that virus evolution played a role in CDV emergence in noncanid hosts following spillover during the outbreak, suggest that host barriers to clinical infection can limit outcomes of CDV spillover in novel host species.
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Affiliation(s)
- Julie K Weckworth
- Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, W. A. Franke College of Forestry and Conservation, University of Montana, Missoula, MT, USA
| | - Brian W Davis
- Department of Veterinary Integrative Biosciences, Texas A&M University College of Veterinary Medicine, TX, USA
| | - Edward Dubovi
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | | | - Craig Packer
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN, USA
| | - Sarah Cleaveland
- The Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Heal and Comparative Medicine, University of Glasgow, Glasgow, UK.,Nelson Mandela African Institution for Science and Technology, Arusha, Tanzania
| | - Meggan E Craft
- Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN, USA
| | - Ernest Eblate
- Tanzania Wildlife Research Institute, Arusha, Tanzania
| | - Michael Schwartz
- Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, W. A. Franke College of Forestry and Conservation, University of Montana, Missoula, MT, USA.,United States Department of Agriculture, Forest Service, National Genomics Center for Wildlife and Fish Conservation, Rocky Mountain Research Station, Missoula, MT, USA
| | - L Scott Mills
- Fisheries, Wildlife, and Conservation Biology Program, Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC, USA
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7
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Muneza AB, Ortiz-Calo W, Packer C, Cusack JJ, Jones T, Palmer MS, Swanson A, Kosmala M, Dickman AJ, Macdonald DW, Montgomery RA. QUANTIFYING THE SEVERITY OF GIRAFFE SKIN DISEASE VIA PHOTOGRAMMETRY ANALYSIS OF CAMERA TRAP DATA. J Wildl Dis 2019; 55:770-781. [PMID: 31009309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Developing techniques to quantify the spread and severity of diseases afflicting wildlife populations is important for disease ecology, animal ecology, and conservation. Giraffes (Giraffa camelopardalis) are in the midst of a dramatic decline, but it is not known whether disease is playing an important role in the broad-scale population reductions. A skin disorder referred to as giraffe skin disease (GSD) was recorded in 1995 in one giraffe population in Uganda. Since then, GSD has been detected in 13 populations in seven African countries, but good descriptions of the severity of this disease are not available. We photogrammetrically analyzed camera trap images from both Ruaha and Serengeti National parks in Tanzania to quantify GSD severity. Giraffe skin disease afflicts the limbs of giraffes in Tanzania, and we quantified severity by measuring the vertical length of the GSD lesion in relation to the total leg length. Applying the Jenks natural breaks algorithm to the lesion proportions that we derived, we classified individual giraffes into disease categories (none, mild, moderate, and severe). Scaling up to the population level, we predicted the proportion of the Ruaha and Serengeti giraffe populations with mild, moderate, and severe GSD. This study serves to demonstrate that camera traps presented an informative platform for examinations of skin disease ecology.
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Affiliation(s)
- Arthur B Muneza
- Research on the Ecology of Carnivores and Their Prey Laboratory, Department of Fisheries and Wildlife, Michigan State University, 480 Wilson Road, 13 Natural Resources Building, East Lansing, Michigan 48824, USA
- Giraffe Conservation Foundation, PO Box 51061 GPO, Nairobi, 00100, Kenya
| | - Waldemar Ortiz-Calo
- Research on the Ecology of Carnivores and Their Prey Laboratory, Department of Fisheries and Wildlife, Michigan State University, 480 Wilson Road, 13 Natural Resources Building, East Lansing, Michigan 48824, USA
| | - Craig Packer
- Department of Ecology, Evolution and Behavior, University of Minnesota, 140 Gortner Laboratory, 1479 Gortner Avenue, St. Paul, Minnesota 55108, USA
| | - Jeremy J Cusack
- Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, UK
| | - Trevor Jones
- Southern Tanzania Elephant Program, PO Box 2494, Iringa, Tanzania
| | - Meredith S Palmer
- Department of Ecology, Evolution and Behavior, University of Minnesota, 140 Gortner Laboratory, 1479 Gortner Avenue, St. Paul, Minnesota 55108, USA
| | - Alexandra Swanson
- Department of Ecology, Evolution and Behavior, University of Minnesota, 140 Gortner Laboratory, 1479 Gortner Avenue, St. Paul, Minnesota 55108, USA
| | - Margaret Kosmala
- Department of Ecology, Evolution and Behavior, University of Minnesota, 140 Gortner Laboratory, 1479 Gortner Avenue, St. Paul, Minnesota 55108, USA
| | - Amy J Dickman
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Abingdon Road, Tubney, Oxon OX13 5QL, UK
| | - David W Macdonald
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Abingdon Road, Tubney, Oxon OX13 5QL, UK
| | - Robert A Montgomery
- Research on the Ecology of Carnivores and Their Prey Laboratory, Department of Fisheries and Wildlife, Michigan State University, 480 Wilson Road, 13 Natural Resources Building, East Lansing, Michigan 48824, USA
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Abingdon Road, Tubney, Oxon OX13 5QL, UK
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Probert JR, Parr CL, Holdo RM, Anderson TM, Archibald S, Courtney Mustaphi CJ, Dobson AP, Donaldson JE, Hopcraft GC, Hempson GP, Morrison TA, Beale CM. Anthropogenic modifications to fire regimes in the wider Serengeti-Mara ecosystem. Glob Chang Biol 2019; 25:3406-3423. [PMID: 31282085 PMCID: PMC6852266 DOI: 10.1111/gcb.14711] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 05/02/2019] [Indexed: 06/09/2023]
Abstract
Fire is a key driver in savannah systems and widely used as a land management tool. Intensifying human land uses are leading to rapid changes in the fire regimes, with consequences for ecosystem functioning and composition. We undertake a novel analysis describing spatial patterns in the fire regime of the Serengeti-Mara ecosystem, document multidecadal temporal changes and investigate the factors underlying these patterns. We used MODIS active fire and burned area products from 2001 to 2014 to identify individual fires; summarizing four characteristics for each detected fire: size, ignition date, time since last fire and radiative power. Using satellite imagery, we estimated the rate of change in the density of livestock bomas as a proxy for livestock density. We used these metrics to model drivers of variation in the four fire characteristics, as well as total number of fires and total area burned. Fires in the Serengeti-Mara show high spatial variability-with number of fires and ignition date mirroring mean annual precipitation. The short-term effect of rainfall decreases fire size and intensity but cumulative rainfall over several years leads to increased standing grass biomass and fuel loads, and, therefore, in larger and hotter fires. Our study reveals dramatic changes over time, with a reduction in total number of fires and total area burned, to the point where some areas now experience virtually no fire. We suggest that increasing livestock numbers are driving this decline, presumably by inhibiting fire spread. These temporal patterns are part of a global decline in total area burned, especially in savannahs, and we caution that ecosystem functioning may have been compromised. Land managers and policy formulators need to factor in rapid fire regime modifications to achieve management objectives and maintain the ecological function of savannah ecosystems.
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Affiliation(s)
- James R. Probert
- Department of Earth, Ocean & Ecological SciencesUniversity of LiverpoolLiverpoolUK
| | - Catherine L. Parr
- Department of Earth, Ocean & Ecological SciencesUniversity of LiverpoolLiverpoolUK
- Centre for African EcologySchool of Animal, Plant and Environmental SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
- Department of Zoology & EntomologyUniversity of PretoriaPretoriaSouth Africa
| | - Ricardo M. Holdo
- Centre for African EcologySchool of Animal, Plant and Environmental SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
- Odum School of EcologyUniversity of GeorgiaAthensGeorgia
| | | | - Sally Archibald
- Centre for African EcologySchool of Animal, Plant and Environmental SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
- Natural Resources and the Environment, CSIRPretoriaSouth Africa
| | - Colin J. Courtney Mustaphi
- Geoecology, Department of Environmental SciencesUniversity of BaselBaselSwitzerland
- Institutionen för arkeologi och antik historiaUppsala UniversitetUppsalaSweden
- York Institute for Tropical Ecosystems, Environment DepartmentUniversity of YorkYorkUK
| | - Andrew P. Dobson
- Ecology and Evolutionary BiologyPrinceton UniversityPrincetonNew Jersey
| | - Jason E. Donaldson
- Centre for African EcologySchool of Animal, Plant and Environmental SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
| | - Grant C. Hopcraft
- Institute of Biodiversity, Animal Health and Comparative MedicineUniversity of GlasgowGlasgowUK
| | - Gareth P. Hempson
- Centre for African EcologySchool of Animal, Plant and Environmental SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
- South African Environmental Observation Network (SAEON), Ndlovu NodePhalaborwaSouth Africa
| | - Thomas A. Morrison
- Institute of Biodiversity, Animal Health and Comparative MedicineUniversity of GlasgowGlasgowUK
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9
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Hepler SA, Erhardt R, Anderson TM. Identifying drivers of spatial variation in occupancy with limited replication camera trap data. Ecology 2018; 99:2152-2158. [PMID: 29901234 DOI: 10.1002/ecy.2396] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 04/22/2018] [Accepted: 04/26/2018] [Indexed: 11/10/2022]
Abstract
Occupancy models are widely used in camera trap studies to analyze species presence, abundance, and geographic distribution, among other important ecological quantities. These models account for imperfect detection using a latent variable to distinguish between true presence/absence and observed detection of a species. Under certain experimental setups, parameter estimation in a latent variable framework can be challenging. Several studies have issued guidelines on the number of independent replicated observations (surveys) needed for each unchanging occupancy field (season) to ensure reliable estimation. In this paper, we present a spatio-temporal occupancy model, and show through a simulation study that it can be fit to data obtained from a single survey per season, so long as the number of seasons is sufficiently large. We include an application using camera-trap data on the Thomson's gazelle in the Serengeti in Tanzania.
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Affiliation(s)
- Staci A Hepler
- Department of Mathematics and Statistics, Wake Forest University, Winston-Salem, North Carolina, USA.,Center for Energy, Environment and Sustainability, Wake Forest University, Winston-Salem, North Carolina, USA
| | - Robert Erhardt
- Department of Mathematics and Statistics, Wake Forest University, Winston-Salem, North Carolina, USA.,Center for Energy, Environment and Sustainability, Wake Forest University, Winston-Salem, North Carolina, USA
| | - T Michael Anderson
- Center for Energy, Environment and Sustainability, Wake Forest University, Winston-Salem, North Carolina, USA.,Department of Biology, Wake Forest University, Winston-Salem, North Carolina, USA
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10
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Seeber PA, Franz M, Dehnhard M, Ganswindt A, Greenwood AD, East ML. Plains zebra (Equus quagga) adrenocortical activity increases during times of large aggregations in the Serengeti ecosystem. Horm Behav 2018; 102:1-9. [PMID: 29630896 DOI: 10.1016/j.yhbeh.2018.04.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 03/19/2018] [Accepted: 04/03/2018] [Indexed: 11/25/2022]
Abstract
Adverse environmental stimuli (stressors) activate the hypothalamic-pituitary-adrenal axis and contribute to allostatic load. This study investigates the contribution of environmental stressors and life history stage to allostatic load in a migratory population of plains zebras (Equus quagga) in the Serengeti ecosystem, in Tanzania, which experiences large local variations in aggregation. We expected higher fGCM response to the environmental stressors of feeding competition, predation pressure and unpredictable social relationships in larger than in smaller aggregations, and in animals at energetically costly life history stages. As the study was conducted during the 2016 El Niño, we did not expect food quality of forage or a lack of water to strongly affect fGCM responses in the dry season. We measured fecal glucocorticoid metabolite (fGCM) concentrations using an enzyme immunoassay (EIA) targeting 11β-hydroxyetiocholanolone and validated its reliability in captive plains zebras. Our results revealed significantly higher fGCM concentrations 1) in large aggregations than in smaller groupings, and 2) in band stallions than in bachelor males. Concentrations of fGCM were not significantly higher in females at the energetically costly life stage of late pregnancy/lactation. The higher allostatic load of stallions associated with females, than bachelor males is likely caused by social stressors. In conclusion, migratory zebras have elevated allostatic loads in large aggregations that probably result from their combined responses to increased feeding competition, predation pressure and various social stressors. Further research is required to disentangle the contribution of these stressors to allostatic load in migratory populations.
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Affiliation(s)
- P A Seeber
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| | - M Franz
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| | - M Dehnhard
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| | - A Ganswindt
- Endocrine Research Laboratory, Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Private Bag XO4, Onderstepoort 0110, South Africa; Mammal Research Institute, Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria 0028, South Africa
| | - A D Greenwood
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany; Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany.
| | - M L East
- Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
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11
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Anderson TM, White S, Davis B, Erhardt R, Palmer M, Swanson A, Kosmala M, Packer C. The spatial distribution of African savannah herbivores: species associations and habitat occupancy in a landscape context. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0314. [PMID: 27502379 DOI: 10.1098/rstb.2015.0314] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2016] [Indexed: 11/12/2022] Open
Abstract
Herbivores play an important role in determining the structure and function of tropical savannahs. Here, we (i) outline a framework for how interactions among large mammalian herbivores, carnivores and environmental variation influence herbivore habitat occupancy in tropical savannahs. We then (ii) use a Bayesian hierarchical model to analyse camera trap data to quantify spatial patterns of habitat occupancy for lions and eight common ungulates of varying body size across an approximately 1100 km(2) landscape in the Serengeti ecosystem. Our results reveal strong positive associations among herbivores at the scale of the entire landscape. Lions were positively associated with migratory ungulates but negatively associated with residents. Herbivore habitat occupancy differed with body size and migratory strategy: large-bodied migrants, at less risk of predation and able to tolerate lower quality food, were associated with high NDVI, while smaller residents, constrained to higher quality forage, avoided these areas. Small herbivores were strongly associated with fires, likely due to the subsequent high-quality regrowth, while larger herbivores avoided burned areas. Body mass was strongly related to herbivore habitat use, with larger species more strongly associated with riverine and woodlands than smaller species. Large-bodied migrants displayed diffuse habitat occupancy, whereas smaller species demonstrated fine-scale occupancy reflecting use of smaller patches of high-quality habitat. Our results demonstrate the emergence of strong positive spatial associations among a diverse group of savannah herbivores, while highlighting species-specific habitat selection strongly determined by herbivore body size.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'.
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Affiliation(s)
- T Michael Anderson
- Department of Biology, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Staci White
- Department of Mathematics and Statistics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Bryant Davis
- Department of Mathematics and Statistics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Rob Erhardt
- Department of Mathematics and Statistics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Meredith Palmer
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN 55108, USA
| | - Alexandra Swanson
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN 55108, USA
| | - Margaret Kosmala
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN 55108, USA
| | - Craig Packer
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN 55108, USA
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12
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Abstract
BACKGROUND Traditional communities have been utilizing animal products for numerous purposes and have for a long time contributed to the accumulation of world knowledge. Local people in Tanzania and elsewhere in Africa, have been using birds including ostriches as pets or their products such as meat, eggs as food; their body parts such as feathers, bones and hide for ornaments but more importantly have used such products in traditional medicine and rituals. Nevertheless, there is a general lack of information about the differences that exist between local people with different cultures, and the best use of such products to improve their livelihoods. This study aimed to determine the use of ostrich products among people residing around Serengeti National Park and explore the potential of improving livelihoods through game ranching. METHODS Use of the products was compared between that of agriculturalists with long hunting traditions in the Serengeti District to the west of Serengeti National Park (SNP) and the largely pastoral community in the Ngorongoro District to the east by using semistructured questionnaires in June 2006. RESULTS A total of 115 respondents were interviewed, and the majority (74.5%) in the Serengeti district admitted that ostriches were mainly hunted for their products by snares, while in the Ngorongoro district, 98.2% of the respondents said that villagers only gathered products such as feathers and eggs. Ostriches were hunted for food, ornamentation, medical and economic purposes, and eggs and oil, which are believed to have medicinal properties, were used for the treatment of various ailments, including asthma. This indigenous knowledge of the medicinal value of ostrich products must be integrated with scientific knowledge to prove the supposed medical efficacy of the products. Ostrich products also had market value and were thus sold to the villagers. CONCLUSION Since it has been found that ostrich products are commercially used, legal establishment of markets through game ranching, might improve local livelihood while simultaneously promoting the conservation of ostriches, whose populations are declining, by reducing hunting pressure. Ostrich farming and conservation education programs are recommended.
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Affiliation(s)
- Flora Magige
- Department of Zoology and Wildlife Conservation, University of Dar es Salaam, P.O. Box 35064, Dar es Salaam, Tanzania
| | - Eivin Røskaft
- Department of Biology, Norwegian University of Science and Technology, Realfagbygget, -7491 Trondheim, NO Norway
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13
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Nikolin VM, Olarte-Castillo XA, Osterrieder N, Hofer H, Dubovi E, Mazzoni CJ, Brunner E, Goller KV, Fyumagwa RD, Moehlman PD, Thierer D, East ML. Canine distemper virus in the Serengeti ecosystem: molecular adaptation to different carnivore species. Mol Ecol 2016; 26:2111-2130. [PMID: 27928865 PMCID: PMC7168383 DOI: 10.1111/mec.13902] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 08/25/2016] [Accepted: 09/02/2016] [Indexed: 12/24/2022]
Abstract
Was the 1993/1994 fatal canine distemper virus (CDV) epidemic in lions and spotted hyaenas in the Serengeti ecosystem caused by the recent spillover of a virulent domestic dog strain or one well adapted to these noncanids? We examine this question using sequence data from 13 'Serengeti' strains including five complete genomes obtained between 1993 and 2011. Phylogenetic and haplotype network analyses reveal that strains from noncanids during the epidemic were more closely related to each other than to those from domestic or wild canids. All noncanid 'Serengeti' strains during the epidemic encoded: (1) one novel substitution G134S in the CDV-V protein; and (2) the rare amino acid combination 519I/549H at two sites under positive selection in the region of the CDV-H protein that binds to SLAM (CD 150) host cell receptors. Worldwide, only a few noncanid strains in the America II lineage encode CDV-H 519I/549H. All canid 'Serengeti' strains during the epidemic coded CDV-V 134G, and CDV-H 519R/549Y, or 519R/549H. A functional assay of cell entry revealed the highest performance by CDV-H proteins encoding 519I/549H in cells expressing lion SLAM receptors, and the highest performance by proteins encoding 519R/549Y, typical of dog strains worldwide, in cells expressing dog SLAM receptors. Our findings are consistent with an epidemic in lions and hyaenas caused by CDV variants better adapted to noncanids than canids, but not with the recent spillover of a dog strain. Our study reveals a greater complexity of CDV molecular epidemiology in multihost environments than previously thought.
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Affiliation(s)
- Veljko M Nikolin
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany.,Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| | | | - Nikolaus Osterrieder
- Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| | - Heribert Hofer
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
| | - Edward Dubovi
- Animal Health Diagnostic Centre, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Camila J Mazzoni
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany.,Berlin Center for Genomics in Biodiversity Research, Königin-Luise-Str. 6-8, 14195, Berlin, Germany
| | - Edgar Brunner
- Department of Medical Statistics, Faculty of Medicine, University of Göttingen, Humboldtallee 32, 37073, Göttingen, Germany
| | - Katja V Goller
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
| | - Robert D Fyumagwa
- Tanzania Wildlife Research Institute, P.O. Box 661, Arusha, Tanzania
| | | | - Dagmar Thierer
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
| | - Marion L East
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
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Kisingo A, Rollins R, Murray G, Dearden P, Clarke M. Evaluating 'good governance': The development of a quantitative tool in the Greater Serengeti Ecosystem. J Environ Manage 2016; 181:749-755. [PMID: 27566933 DOI: 10.1016/j.jenvman.2016.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 07/27/2016] [Accepted: 08/02/2016] [Indexed: 06/06/2023]
Abstract
Protected areas (PAs) can provide important benefits to conservation and to communities. A key factor in the effective delivery of these benefits is the role of governance. There has been a growth in research developing frameworks to evaluate 'good' PA governance, usually drawing on a set of principles that are associated with groups of indicators. In contrast to dominant qualitative approaches, this paper describes the development of a quantitative method for measuring effectiveness of protected area governance, as perceived by stakeholders in the Greater Serengeti Ecosystem in Tanzania. The research developed a quantitative method for developing effectiveness measures of PA governance, using a set of 65 statements related to governance principles developed from a literature review. The instrument was administered to 389 individuals from communities located near PAs in the Greater Serengeti Ecosystem. The results of a factor analysis suggest that statements load onto 10 factors that demonstrate high psychometric validity as measured by factor loadings, explained variance, and Cronbach's alpha reliability. The ten common factors that were extracted were: 1) legitimacy, 2) transparency and accountability, 3) responsiveness, 4) fairness, 5) participation, 6) ecosystem based management (EBM) and connectivity, 7) resilience, 8) achievements, 9) consensus orientation, and 10) power. The paper concludes that quantitative surveys can be used to evaluate governance of protected areas from a community-level perspective.
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Affiliation(s)
- Alex Kisingo
- College of African Wildlife Management, Tanzania
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15
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Mahapatra M, Sayalel K, Muniraju M, Eblate E, Fyumagwa R, Shilinde L, Mdaki M, Keyyu J, Parida S, Kock R. Spillover of Peste des Petits Ruminants Virus from Domestic to Wild Ruminants in the Serengeti Ecosystem, Tanzania. Emerg Infect Dis 2016; 21:2230-4. [PMID: 26583961 PMCID: PMC4672450 DOI: 10.3201/eid2112.150223] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We tested wildlife inhabiting areas near domestic livestock, pastures, and water sources in the Ngorongoro district in the Serengeti ecosystem of northern Tanzania and found 63% seropositivity for peste des petits ruminants virus. Sequencing of the viral genome from sick sheep in the area confirmed lineage II virus circulation.
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16
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Cusack JJ, Swanson A, Coulson T, Packer C, Carbone C, Dickman AJ, Kosmala M, Lintott C, Rowcliffe JM. Applying a random encounter model to estimate lion density from camera traps in Serengeti National Park, Tanzania. J Wildl Manage 2015; 79:1014-1021. [PMID: 26640297 PMCID: PMC4657488 DOI: 10.1002/jwmg.902] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Accepted: 04/21/2015] [Indexed: 11/10/2022]
Abstract
The random encounter model (REM) is a novel method for estimating animal density from camera trap data without the need for individual recognition. It has never been used to estimate the density of large carnivore species, despite these being the focus of most camera trap studies worldwide. In this context, we applied the REM to estimate the density of female lions (Panthera leo) from camera traps implemented in Serengeti National Park, Tanzania, comparing estimates to reference values derived from pride census data. More specifically, we attempted to account for bias resulting from non-random camera placement at lion resting sites under isolated trees by comparing estimates derived from night versus day photographs, between dry and wet seasons, and between habitats that differ in their amount of tree cover. Overall, we recorded 169 and 163 independent photographic events of female lions from 7,608 and 12,137 camera trap days carried out in the dry season of 2010 and the wet season of 2011, respectively. Although all REM models considered over-estimated female lion density, models that considered only night-time events resulted in estimates that were much less biased relative to those based on all photographic events. We conclude that restricting REM estimation to periods and habitats in which animal movement is more likely to be random with respect to cameras can help reduce bias in estimates of density for female Serengeti lions. We highlight that accurate REM estimates will nonetheless be dependent on reliable measures of average speed of animal movement and camera detection zone dimensions. © 2015 The Authors. Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.
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Affiliation(s)
- Jeremy J Cusack
- Department of Zoology, University of Oxford, The Tinbergen Building South Parks Road, Oxford OX1 3PS, United Kingdom, and Institute of Zoology, Zoological Society of London, London NW1 4RY, United Kingdom
| | - Alexandra Swanson
- Department of Ecology, Evolution and Behavior University of Minnesota MN, 55108, USA
| | - Tim Coulson
- Department of Zoology, University of Oxford Oxford OX1 3PS, United Kingdom
| | - Craig Packer
- Department of Ecology, Evolution and Behavior, University of Minnesota MN, 55108, USA
| | - Chris Carbone
- Institute of Zoology, Zoological Society of London London NW1 4RY, United Kingdom
| | - Amy J Dickman
- Department of Zoology, University of Oxford Oxford OX1 3PS, United Kingdom
| | - Margaret Kosmala
- Department of Ecology, Evolution and Behavior University of Minnesota MN, 55108, USA
| | - Chris Lintott
- Department of Physics, University of Oxford Oxford OX1 3RH, United Kingdom
| | - J Marcus Rowcliffe
- Institute of Zoology, Zoological Society of London London NW1 4RY, United Kingdom
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17
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Abstract
The effects of grazing on soil organic carbon (SOC) dynamics, particularly in the tropics, are still poorly understood. Plant compensation to grazing, whereby plants maintain leaf area (C input capacity) despite consumption (C removal) by grazers, has been demonstrated in tropical grasslands but its influence on SOC is largely unexplored. Here, the effect of grazing on plant leaf area index (LAI) was measured in a field experiment in Serengeti National Park, Tanzania. LAI changed little for grazing intensities up to 70%. The response curve of LAI versus grazing intensity was used in a mass balance model, called SNAP, of SOC dynamics based on previous data from the Serengeti. The model predicted SOC to increase at intermediate grazing intensity, but then to decline rapidly at the highest grazing intensities. The SNAP model predictions were compared with observed SOC stocks in the 24 grazed plots of a 10-year grazing exclosure experiment at eight sites across the park that varied in mean annual rainfall, soil texture, grazing intensity and plant lignin and cellulose. The model predicted current SOC stocks very well (R (2) > 0.75), and suggests that compensatory plant responses to grazing are an important means of how herbivores might maintain or increase SOC in tropical grasslands.
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Affiliation(s)
- Mark E Ritchie
- Department of Biology , Syracuse University , Syracuse, NY , USA
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18
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East ML, Kurze C, Wilhelm K, Benhaiem S, Hofer H. Factors influencing Dipylidium sp. infection in a free-ranging social carnivore, the spotted hyaena (Crocuta crocuta). Int J Parasitol Parasites Wildl 2013; 2:257-65. [PMID: 24533344 PMCID: PMC3862517 DOI: 10.1016/j.ijppaw.2013.09.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 08/28/2013] [Accepted: 09/03/2013] [Indexed: 01/08/2023]
Abstract
We investigated Dipylidium infection in a social carnivore, the spotted hyaena. Infection predominantly occurred in juveniles, most adults were probably immune. Juvenile infection prevalence increased with the number of hyaenas visiting dens. Infection prevalence in juveniles decreased when they were least well fed. The use of communal dens maintains Dipylidium infection in spotted hyaena clans.
We provide the first genetic sequence data for a Dipylidium species from a wild carnivore plus an analysis of the effects of ecological, demographic, physiological and behavioural factors on Dipylidium sp. infection prevalence in a social carnivore, the spotted hyaena (Crocuta crocuta), in the Serengeti National Park, Tanzania. Our sequence data from a mitochondrial gene fragment (1176 base pair long) had a similarity of between 99% and 89% to Dipylidium caninum. We determined infection prevalence in 146 faecal samples from 124 known animals in three social groups (termed clans) using molecular screening and Dipylidium proglottid presence. Our analysis revealed significantly higher infection prevalence in juveniles (55%) than adults (15.8%), indicating that predominantly juveniles maintained infection in clans. The likelihood of infection in juveniles significantly: (1) increased as the number of adults and older juveniles (>6 months) at communal dens increased, implying a positive relationship between this factor and the size of the intermediate host (probably a flea species) population at communal dens; (2) decreased as the number of younger juveniles (<6 months) increased, suggesting that the chance of susceptible juveniles ingesting infected fleas during self-grooming declined as the number of infected fleas per younger juvenile declined; and (3) decreased during periods of low prey abundance in clan territories when an increased reliance on long-distances foraging excursions reduces the number of clan members visiting communal dens, possibly resulting in a decline in flea populations at dens. Long-distance foraging also increases the intervals (in days) between nursing visits by lactating females to their offspring. Lengthy intervals between milk intake by infected juveniles may reduce adult Dipylidium fecundity and hence decrease infection prevalence in the den flea population. Our study provides useful insights into Dipylidium epidemiology in a social carnivore population subject to large fluctuations in prey abundance.
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Affiliation(s)
- Marion L East
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315 Berlin, Germany
| | - Christoph Kurze
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315 Berlin, Germany ; Institute of Biology, Freie Universität Berlin, Philippstr. 13, 10115 Berlin, Germany
| | - Kerstin Wilhelm
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315 Berlin, Germany
| | - Sarah Benhaiem
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315 Berlin, Germany
| | - Heribert Hofer
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315 Berlin, Germany
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19
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Strauch AM, Muller JM, Almedom AM. Exploring the dynamics of social-ecological resilience in East and West Africa: Preliminary evidence from Tanzania and Niger. Afr Health Sci 2008; 8 Suppl 1:S28-S35. [PMID: 21448367 PMCID: PMC3060726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
BACKGROUND Social-ecological resilience refers to the dynamic process of adaptive learning, reorganization and meaning-making demonstrated in linked human, animal, and plant ecosystems often organized in formal and/or informal social institutions, as they anticipate, withstand and/or judiciously engage with adversity while maintaining function without fundamentally losing their identity. OBJECTIVE To present two sets of examples that illustrate the complex ways in which transformation and persistence, two key aspects of the adaptive cycle may work together to preserve established patterns of human and/or animal uses of water resources and food plant species, in rural East and West Africa, respectively around the Serengeti National Park (Tanzania), and "Park W" (Niger), with the aim of identifying possible indicators of social-ecological resilience. METHODS Selective combinations of ecological and anthropological, quantitative and qualitative methods, including participatory tools of investigation and analysis. RESULTS AND DISCUSSION Our preliminary results are presented with minimal commentary and discussion in order to avoid hasty and/or unwarranted interpretation of the ongoing purposely iterative processes of investigation and analysis in the two study sites. Nevertheless we have identified a number of possible indicators of social-ecological resilience that may be tested in other localities in Africa and elsewhere.
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Affiliation(s)
- A M Strauch
- Biology Department, Tufts University, 163 Packard Ave, Medford, MA 02155, USA.
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