87 research outputs found

    \u3cem\u3eThe Director\u27s Desk\u3c/em\u3e It’s a Bear Market for Research

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    \u3cem\u3eThe Director\u27s Desk\u3c/em\u3e Why this Journal was Created

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    \u3cem\u3eThe Director\u27s Desk\u3c/em\u3e Standardizing the Data on Wildlife-Vehicle Collisions

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    There are few more dramatic manifestations of human– wildlife conflict than squealing brakes, a sickening crunch, flying gravel, and then silence except for the weakly spasmodic scrabbling of a semipulverized deer as it lies dying on the side of a highway. The scientific analysis of wildlife–vehicle collisions is an applied science of increasing importance throughout the industrialized world, but it is yet woefully deficient in theoretical underpinnings and standardized methodology. The overarching discipline of road ecology has only recently gained formal recognition through the publication of the first definitive book on this topic by Forman et al. (2003). And until now, there has not been a target journal in which research on the problem of wildlife– vehicle collisions can be highlighted and developed within a focused readership

    The Differences Between Rewilding and Restoring an Ecologically Degraded Landscape

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    Rewilding is a developing concept in ecosystem stewardship that involves reorganizing and regenerating wildness in an ecologically degraded landscape, with present and future ecosystem function being of higher consideration than historical benchmark conditions. This approach differs from ecosystem restoration but the two concepts are often conflated because (a) they both rely on similar management actions (at least initially) and (b) it can be erroneously assumed that they both aim for similar states of wildness. Rewilding and restoring both influence biodiversity, and common management actions such as species reintroductions (e.g. beavers or wolves) can be integral to a rewilding project. However, in contrast with restoration, rewilding has lower fidelity to taxonomic precedent and promotes taxonomic substitutions for extinct native species that once underpinned the delivery of key ecological functions. We suggest the adaptive cycle as the appropriate conceptual framework in which to distinguish rewilding from ecosystem restoration. The focus of restoration ecology is to return an ecosystem to as close to its former state as is possible after a major disturbance, by directly reinstating it on the ‘foreloop’ of the adaptive cycle. In contrast, rewilding draws from the ‘backloop’ by promoting reorganization and redevelopment of the ecosystem under changing environmental conditions. If environmental conditions have changed so significantly that a regime shift is inevitable, then rewilding can facilitate the development of a novel ecosystem to sustain the provision of ecosystem services. Synthesis and applications. Rewilding and restoring both have their places in biodiversity conservation. In each case, their respective merits should be weighed in relation to stakeholder priorities, prevailing and predicted environmental conditions, the level of biological organization targeted for management, and existing and future management capacity. We provide simple schematic decision‐pathways to assist in exploring whether an ecologically degraded landscape might be a candidate for restoration, active rewilding, or passive rewilding

    Steps to operationalize a rewilding decision : focus on functional types

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    DATA AVAILABILITY STATEMENT : The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.If transparent and inclusive stakeholder discussion delivers a consensus for active rewilding, then five steps are recommended for operationalizing that decision, focused initially on the large herbivore assemblage. Consideration of large predators could follow, contingent upon the establishment of prey populations. First, determine the potential biomass density (kg/km2) of large mammalian herbivores in the target landscape. Regression models based on rainfall or primary productivity are helpful if applicable, otherwise comparative studies are needed. Second, use empirical data from reference ecosystems to apportion biomass density among functional types, crudely defined by body size and feeding type (grazer, browser, mixed feeder). Third, identify specific functional traits (coarse grazing, endozoochory, etc.) of particular local importance. Fourth, identify species within each functional type that are already present, estimate their potential biomass densities, and thus identify the shortfall within each cell of the body size x feeding type matrix. A candidate set of native and non-native (surrogate) species is then identified to make up the shortfalls. This is followed by an iterative process of estimating equilibrium population sizes, stakeholder acceptance, and viability of each potential population. Fifth, stakeholders must be inclusively re-engaged to visualize the potential assemblage, its expected functional interactions, the ecosystem services to be delivered, and the long-term costs (including opportunity costs) and benefits. When a plan is supported, local stakeholders should be integrated as active participants in the implementation, monitoring, and championing of their rewilding project.Utah State University and, previously, the University of Pretoria.http://www.frontiersin.org/Ecology_and_Evolutionam2024Mammal Research InstituteZoology and EntomologySDG-15:Life on lan

    Improving the effectiveness of interventions to balance conservation and development: a conceptual framework

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    There are numerous case studies around the world describing integrated conservation and development projects (ICDPs). Recently some localized syntheses have been published that use sophisticated statistics to identify patterns and causal linkages, but no attempt has yet been made to draw together lessons from across the globe. This paper is an attempt to provide a framework for such an analysis. A set of lessons is proposed for improving the prospects of ICDPs by giving consideration to each of the five capitals: natural, social, human, built, and financial. The language of ICDPs has been adopted by development agencies of all persuasions. There is now some urgency to identify the characteristics of the environment and the community in which success is most likely. This paper is intended as a step in that direction

    Ecological implications of bovine tuberculosis in African buffalo herds

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    Following the recent invasion of bovine tuberculosis (BTB) into the Kruger National Park, South Africa, we conducted a study on the maintenance host, African buffalo, to investigate associations between BTB prevalence and calf:cow ratio, age structure, body condition, and endoparasite load. Statistical analyses compared herds of zero, medium (1–40%), and high (\u3e40%) BTB prevalence. To control for ecological variation across the park we collected data in northern, central, and southern regions and restricted some analyses to particular regions of the park. Body condition declined over the course of the 2001 dry season, and buffaloes in the southern region of the park, with the highest BTB prevalence, were in worse condition than buffaloes in the northern region (which receives less annual rainfall but is still virtually BTB-free). Herd-level analyses of the entire park, the south and central regions, and just the southern region all indicated that herds of higher BTB prevalence were in worse condition and lost condition faster through the dry season than herds of lower BTB prevalence. Fecal endoparasite egg counts increased during the dry season and were associated with both decreased body condition and increased BTB prevalence. Although we did not detect any obvious effect of BTB on the age structure of the buffalo population, our findings indicate early symptoms of wider scale BTB-related ecological disturbances: buffalo herds with high BTB prevalence appear more vulnerable to drought (because of a decrease in body condition and an increase in endoparasite load), and because lions selectively kill weak buffaloes their prey base is accumulating a disproportionately high prevalence of BTB, to which lions are susceptible

    Interactions between megaherbivores and microherbivores : elephant browsing reduces host plant quality for caterpillars

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    Direct effects of herbivory, and indirect effects through induced responses to herbivory, can both influence the susceptibility of plants to subsequent attacks by herbivores. There has, however, been very little research (if any) to investigate how the large-scale effects of browsing by megaherbivores (.1000 kg body mass) on woody plants might influence the subsequent use of those plants by phytophagous insects. We conducted a field study in Kruger National Park, South Africa, to investigate whether browsing by elephants (Loxodonta africana) on mopane trees (Colophospermum mopane) had any influence on the subsequent selection of those trees by ovipositing mopane moths (Imbrasia belina). Our results showed that, after controlling for differences in canopy volume, the density of egg masses was almost halved in mopane woodlands recovering from severe elephant browsing in the previous season. This is despite the regrowth on heavily browsed trees having lower tannin:protein ratios and longer shoots. Our suggested explanation is that large monophagous caterpillars can only feed in the canopies of the trees in which they hatch and so the quantity of food in each canopy is more important than its quality. There are implications for the sustainable harvesting of mopane caterpillars, which represent an important food resource for rural communities in southern Africa. Future avenues for research include patch selection by large herbivores in response to local nutrient enrichment by frass deposited during caterpillar outbreaks.The National Research Foundation (GUN 2053601 to J. T. du Toit).http://www.esajournals.orgam2014ab201

    Population status and distribution modelling of the critically endangered riverine rabbit (Bunolagus monticularis)

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    The Riverine Rabbit (Bunolagus monticularis), a habitat specialist, is one of the most endangered mammals in southern Africa due to the large-scale fragmentation of Karoo riverine vegetation in South Africa that it inhabits. B. monticularis is an important indicator of ecosystem health and an umbrella species for conservation of the unique riverine ecosystems of the Karoo and the important ecological processes they maintain. This study aimed to contribute towards our understanding of B. monticularis through an assessment of historical survey data to better understand population status and distribution. Geospatial analysis using GIS and distribution modelling was done using Maxent. Extent of occurrence for the species is 54,227 km2 and area of occupancy 2,943 km2. Population size estimates of between 157 and 207 mature individuals indicate extremely low population size for B. monticularis and along with the estimate that no subpopulation contains more than 50 mature individuals, supports the species’ continued listing as Critically Endangered under IUCN Red List criteria C2a(i). Maxent models performed well in terms of predictive ability and fit and continue to be a useful tool for assessing potential future conservation and management actions for this species.START Doctoral Fellowship Program, University of Pretoria, National Research Foundation, Wildlife Conservation Society, Commonwealth Scholarship Commission, Pittsburgh Zoo, Chicago Zoological Society, Endangered Wildlife Trust and GeoTerraImage.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-20282017-06-30hb2016Zoology and Entomolog

    Iodine as an alleviator of bromine toxicity in thyroid, liver and kidney of broiler chickens

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    The study pursued the hypothesis that bromine (Br) in drinking water at levels > 0.01 mg Br/L may have detrimental effects on the liver, kidneys and thyroid and the thyroid hormones T3 and T4 and that iodine (I) may alleviate the potential hazardous effect of Br. The research was done with mixed Ross broiler chickens over a 42-day post-hatch growth period. The trial design was six treatments, T1: 0 mg Br/L and 0 mg I/L; T2: 1 mg Br/L and 0 mg I/L; T3: 3 mg Br/L and 0 mg I/L; T4: 0 mg Br/L and 0.7 mg I/L; T5: 1 mg Br/L and 0.7 mg I/L; and T6: 3 mg Br/L and 0.7 mg I/L delivered via drinking water and three replicates per treatment with 30 birds per replicate. The effect of Br on T3 and T4 levels overall was non-significant, but T3 and T4 levels decreased between Weeks 4 and 6 with a significant effect at Week 6 on T3. Br had an overall effect on the thyroid gland (P = 0.0457), liver (P = 0.0025) and kidney (P = 0.0032), and had accumulated in these three organs. Histopathological assessment showed explicit damage to the livers that received the Br treatments. Iodine (0.07 mg/L) ameliorated the negative effects of high Br (3 mg/L Br) concentration and ingestion.http://www.elsevier.com/locate/livscihj2017Animal and Wildlife Science
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