9 results match your criteria: "Plant and Environmental Sciences University of the Witwatersrand Johannesburg South Africa.[Affiliation]"

Trade-offs between food acquisition and predator avoidance shape the landscape-scale movements of herbivores. These movements create landscape features, such as game trails, which are paths that animals use repeatedly to traverse the landscape. As such, these trails integrate behavioral trade-offs over space and time.

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Carnivora occupy many ecological niches fundamental to ecosystem functioning. Within this diverse order, carnivore species compete to establish dominance, ensure survival and maintain fitness. Subordinate carnivores must, therefore, adapt their behaviour to coexist with dominant species.

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Time from birth or hatching to the first shed (postnatal ecdysis) in snakes ranges from about an hour to several weeks depending upon the species. We assessed patterns in time to postnatal ecdysis in 102 snake species for which we could source appropriate information, covering 2.6% of all extant snake species, and related measures to various biological traits.

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Article Synopsis
  • - Frequent grazing can lead to the creation of high-quality grazing lawns that attract many grazers, but it can also result in overgrazed areas with poor grass quality and low grazers, making the outcome highly dependent on environmental conditions.
  • - A study of 33 grass communities in eastern South Africa and Tanzania identified four types of grass growth forms, including two that are palatable and support grazing lawns, and two that are of low forage value and are avoided by grazers.
  • - Grazing lawns are influenced by environmental factors, with certain grasses thriving in dry, sandy areas and others in wetter, clay-rich soils; monitoring these lawns is crucial to prevent overgrazing, especially since tufted grasses are more susceptible to degradation
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Conservation translocations have become an important management tool, particularly for large wildlife species such as the lion (). When planning translocations, the genetic background of populations needs to be taken into account; failure to do so risks disrupting existing patterns of genetic variation, ultimately leading to genetic homogenization, and thereby reducing resilience and adaptability of the species. We urge wildlife managers to include knowledge of the genetic background of source/target populations, as well as species-wide patterns, in any management intervention.

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Fire and frost represent two major hurdles for the persistence of trees in open grassy biomes and have both been proposed as drivers of grassland-forest boundaries in Africa.We assess the response of young tree seedlings, which represent a vulnerable stage in tree recruitment, to traumatic fire and frost disturbances.In a greenhouse experiment, we investigated how seedling traits predicted survival and resprouting ability in response to fire versus frost; we characterized survival strategies of seedlings in response to the two disturbances, and we documented how the architecture of surviving seedlings is affected by fire versus frost injury.

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  • The study explores global predictions of plant community traits to better understand their responses to environmental changes, focusing on assessing the reliability of these predictions.
  • Utilizing an ensemble modeling approach, researchers predicted plant traits like height and leaf area using locally sourced data while evaluating model accuracy and ecological realism.
  • Results showed that while some traits could be reliably predicted with high data quality, leaf nitrogen concentrations were less reliable; the ensemble method outperformed individual models, especially in regions like African deserts and the Arctic.
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Abandoned cattle () kraals are sources of habitat heterogeneity in dystrophic semi-arid African savannas with a strong positive effect on soil nutrients and plant productivity. However, little is known regarding how macro-invertebrate assemblages vary between abandoned kraals and the surrounding savanna matrix. We tested whether herbaceous biomass and basal and aerial covers and soil nutrients have an effect on aboveground and belowground macro-invertebrate assemblages.

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Studies on resource sharing and partitioning generally consider species that occur in the same habitat. However, subsidies between linked habitats, such as streams and riparian zones, create potential for competition between populations which never directly interact. Evidence suggests that the abundance of riparian consumers declines after fish invasion and a subsequent increase in resource sharing of emerging insects.

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