Research Outputs (Animal, Plant and Environmental Sciences)

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Browsing Research Outputs (Animal, Plant and Environmental Sciences) by Keyword "Africa"

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    Comparative ethnoentomology of edible stinkbugs in southern Africa and sustainable management considerations
    (BioMed Central, 2013) Catherine Maria Dzerefos, C.M.; Witkowski, E.T.F.; Toms, R.
    Insects, such as stinkbugs, are able to produce noxious defence chemicals to ward off predators, nevertheless, some ethnic groups have recipes to render them delicious. We provide an example of edible stinkbugs (Encosternum delegorguei) used by two locally separate ethnic groups in South Africa, the Vhavenda and Mapulana, with a third group, the Bolobedu using them for commercial purposes. Structured interview schedules and observations with 106 harvesters were conducted to determine differences in use, nomenclature and oral history, methods of collection and preparation as well as perceptions pertaining to availability. The stinkbugs’ foul defence chemical and flight response necessitates nocturnal harvesting when the insect is immobilised by cold. The defence chemical stains the skin and affects vision yet protective gear is not worn. Damage to host trees was recorded when harvesters poached from plantations or private land, whereas, in communal-lands, sustainable methods were preferred. The legitimisation of stinkbug harvesting and introduction of a collection funnel could reduce conflicts with managers of plantations and private land. Two methods to remove the defence chemical for increased palatability were used. Preparation methods differed in whether or not water was used and also whether the head was left intact or removed. Stinkbugs have numerous medicinal uses, in particular as a hangover cure. Awareness and optimal use of beneficial insects, such as stinkbugs, in rural areas could lead to a reconsideration of current environmental management strategies, where harvesters act as habitat stewards and clearing, grazing or burning indigenous vegetation is kept to a minimum.
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    The consequences of replacing wildlife with livestock in Africa
    (Scientific Reports, 2017-12-01) Hempson, G.P.; Archibald, S.; Bond, W.J.
    The extirpation of native wildlife species and widespread establishment of livestock farming has dramatically distorted large mammal herbivore communities across the globe. Ecological theory suggests that these shifts in the form and the intensity of herbivory have had substantial impacts on a range of ecosystem processes, but for most ecosystems it is impossible to quantify these changes accurately. We address these challenges using species-level biomass data from sub-Saharan Africa for both present day and reconstructed historical herbivore communities. Our analyses reveal pronounced herbivore biomass losses in wetter areas and substantial biomass increases and functional type turnover in arid regions. Fire prevalence is likely to have been altered over vast areas where grazer biomass has transitioned to above or below the threshold at which grass fuel reduction can suppress fire. Overall, shifts in the functional composition of herbivore communities promote an expansion of woody cover. Total herbivore methane emissions have more than doubled, but lateral nutrient diffusion capacity is below 5% of past levels. The release of fundamental ecological constraints on herbivore communities in arid regions appears to pose greater threats to ecosystem function than do biomass losses in mesic regions, where fire remains the major consumer.
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    Risks to Birds Traded for African Traditional Medicine: A Quantitative Assessment
    (PLoS ONE, 2014-08-27) Williams, V.L.; Cunningham, A.B.; Kemp, A.C.; Bruyns, R.K.
    Few regional or continent-wide assessments of bird use for traditional medicine have been attempted anywhere in the world. Africa has the highest known diversity of bird species used for this purpose. This study assesses the vulnerability of 354 bird species used for traditional medicine in 25 African countries, from 205 genera, 70 families, and 25 orders. The orders most represented were Passeriformes (107 species), Falconiformes (45 species), and Coraciiformes (24 species), and the families Accipitridae (37 species), Ardeidae (15 species), and Bucerotidae (12 species). The Barn owl (Tyto alba) was the most widely sold species (seven countries). The similarity of avifaunal orders traded is high (analogous to ‘‘morphospecies’’, and using Sørensen’s index), which suggests opportunities for a common understanding of cultural factors driving demand. The highest similarity was between bird orders sold in markets of Benin vs. Burkina Faso (90%), but even bird orders sold in two geographically separated countries (Benin vs. South Africa and Nigeria vs. South Africa) were 87% and 81% similar, respectively. Rabinowitz’s ‘‘7 forms of rarity’’ model, used to group species according to commonness or rarity, indicated that 24% of traded bird species are very common, locally abundant in several habitats, and occur over a large geographical area, but 10% are rare, occur in low numbers in specific habitats, and over a small geographical area. The order with the highest proportion of rare species was the Musophagiformes. An analysis of species mass (as a proxy for size) indicated that large and/or conspicuous species tend to be targeted by harvesters for the traditional medicine trade. Furthermore, based on cluster analyses for species groups of similar risk, vultures, hornbills, and other large avifauna, such as bustards, are most threatened by selective harvesting and should be prioritised for conservation action.