Browsing RESEARCH: Robertson, M by Issue Date
Now showing items 1-20 of 43
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Ecological niche modeling of the invasive potential of Nile tilapia Oreochromis niloticus in African river systems: concerns and implications for the conservation of indigenous congenerics
(2013-06-30)This study applied ecological niche models to determine the potential invasive range of Nile tilapia, Oreochromis niloticus, with a particular focus on river systems in southern Africa where it is now established and ... -
Elevation–diversity patterns through space and time: ant communities of the Maloti-Drakensberg Mountains of southern Africa
(John Wiley & Sons Ltd, 2014)Aim Patterns of biological diversity are often investigated across space but little work has attempted to explore the consistency of such observations through time. Here, our aim was to understand the patterns of diversity ... -
Predicting the potential distribution of invasive silver carp Hypophthalmichthys molitrix in South Africa
(NISC (Pty) Ltd, 2014)Predicting the potential geographical distribution and spread of non-native species is of major concern to ecologists. Silver carp Hypophthalmichthys molitrix, ranked as one of the world’s 100 worst invasive species, were ... -
Invasion trajectory of alien trees: the role of introduction pathway and planting history
(John Wiley & Sons Ltd., 2014)Global change is driving a massive rearrangement of the world’s biota. Trajectories of distributional shifts are shaped by species traits, the recipient environment and driving forces with many of the driving forces directly ... -
Forestry trial data can be used to evaluate climate-based species distribution models in predicting tree invasions
(Pensoft Publishers, 2014)Climate is frequently used to predict the outcome of species introductions based on the results from species distribution models (SDMs). However, despite the widespread use of SDMs for pre- and post-border risk assessments, ... -
Spatially-explicit estimation of geographical representation in large-scale species distribution datasets
(Public Library of Science, 2014-01)Much ecological research relies on existing multispecies distribution datasets. Such datasets, however, can vary considerably in quality, extent, resolution or taxonomic coverage. We provide a framework for a spatially-explicit ... -
A standardized set of metrics to assess and monitor tree invasions
(Springer, 2014-03)Scientists, managers, and policy-makers need functional and effective metrics to improve our understanding and management of biological invasions. Such metrics would help to assess progress towards management goals, ... -
A simple, rapid methodology for developing invasive species watch lists
(2014-11)Biosecurity schemes aim to prevent the introduction of species with a high invasion potential, without unduly restricting personal freedom and commercial activities. But invasive species risk assessments are time consuming, ... -
Contrasting species and functional beta diversity in montane ant assemblages
(John Wiley & Sons Ltd, 2015)Aim Beta diversity describes the variation in species composition between sites and can be used to infer why different species occupy different parts of the globe. It can be viewed in a number of ways. First, it can be ... -
Introduced and invasive cactus species: a global review
(Oxford University Press, 2015)Understanding which species are introduced and become invasive, and why, are central questions in invasion science. Comparative studies on model taxa have provided important insights, but much more needs to be done to ... -
Annual monitoring reveals rapid upward movement of exotic plants in a montane ecosystem
(Springer, 2015)There is increasing evidence that invasive species are threating montane ecosystems globally. However, trends in species distribution are difficult to observe directly due to a lack of data with suitable spatio-temporal ... -
An assessment of the information content of South African alien species databases
(AOSIS Publishing, 2015)National alien species databases indicate the state of a country’s biodiversity and provide useful data for research on invasion biology and the management of invasions. In South Africa there are several different published ... -
Invasion debt – quantifying future biological invasions
(John Wiley & Sons Ltd, 2016)Aim We develop a framework for quantifying invasions based on lagged trends in invasions (‘invasion debt’) with the aim of identifying appropriate metrics to quantify delayed responses at different invasion stages – from ... -
Trophic ecology and persistence of invasive silver carp Hypophthalmichthys molitrix in an oligotrophic South African impoundment
(NISC (Pty) Ltd and Taylor & Francis, 2016)The alien invasive silver carp Hypophthalmichthys molitrix established a self-sustaining feral population in an oligotrophic impoundment, Flag Boshielo Dam, in South Africa. The ability of this population to persist in a ... -
Reconsidering environmental diversity (ED) as a biodiversity surrogacy strategy
(Elsevier Ltd., 2016)Environmental Diversity (ED) has been proposed as a potential biodiversity surrogate for use in spatial biodiversity planning. The concept is based on the premise that differences in species composition between areas are ... -
Understanding and managing the introduction pathways of alien taxa: South Africa as a case study
(Springer, 2016)For the effective prevention of biological invasions, the pathways responsible for introductions must be understood and managed. However introduction pathways, particularly for developing nations, have been understudied. ... -
Ant assemblages have darker and larger members in cold environments
(John Wiley & Sons Ltd, 2016)Aim In ectotherms, the colour of an individual’s cuticle may have important thermoregulatory and protective consequences. In cool environments, ectotherms should be darker, to maximize heat gain, and larger, to minimize ...