36 Works

Can time-to-detection models with fewer survey replicates provide a robust alternative to traditional site-occupancy models?

Dominic Henry, Alan Lee & Res Altwegg
Occupancy models are widely used in ecology because they explicitly separate the observation and state processes and hence account for imperfect species detection. Traditional occupancy models that record detection/non-detection (DND) of a species typically rely on either spatial or temporal survey replication to estimate model parameters. Recording the time until a species is first encountered after starting a survey is often possible with little extra effort and such time-to-detection (TTD) surveys may be more efficient...

Foraging in a dynamic environment: response of four sympatric sub-Antarctic albatross species to interannual environmental variability

Tegan Carpenter-Kling, Ryan Reisinger, Florian Orgeret, Maelle Connan, Kim Stevens, Peter Ryan, Azwianewi Makhado & Pierre Pistorius
Seasonal and annual climate variations are linked to fluctuations in the abundance and distribution of resources, posing a significant challenge to animals that need to adjust their foraging behaviour accordingly. Particularly during adverse conditions, and while energetically constrained when breeding, animals ideally need to be flexible in their foraging behaviour. Such behavioural plasticity may separate ‘winners’ from ‘losers’ in light of rapid environmental changes due to climate change. Here, the foraging behaviour of four sub-Antarctic...

Survey of Jewish South Africans 2005

Consuming Urban Poverty Survey 2016-2017

Surplus People Project Survey 1980-1981

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OHS-LFS Consistent Series Weights 1994-2007

Nicola Branson

Employers and Self Employed Series 2001-2013

Epiphytic bryophyte diversity and range distributions along an elevational gradient in Marojejy, Madagascar

Lovanomenjanahary Marline, Claudine Ah-Peng & Terry Hedderson
Describing spatial variation in species richness and understanding its links to ecological mechanisms are complementary approaches for explaining geographical patterns of richness. The study of elevational gradients holds enormous potential for understanding the factors underlying global diversity. This paper investigates the pattern of species richness and range-size distribution of epiphytic bryophytes along an elevational gradient in Marojejy National Park, North-east Madagascar. The main objectives are to describe bryophyte species composition and endemism in Marojejy National...

Data from: A predictive model for improving placement of wind turbines to minimise collision risk potential for a large soaring raptor

Megan Murgatroyd, Willem Bouten & Arjun Amar
1. With the rapid growth of wind energy developments worldwide, it is critical that the negative impacts on wildlife are considered and mitigated. This includes minimising the numbers of large soaring raptors which are killed when they collide with wind turbines. 2. To reduce the likelihood of raptor collisions, turbines should be placed at locations which are least used by sensitive species. For resident or breeding species, this is often delineated crudely through the use...

Data from: Urbanization is associated with increased breeding rate, but decreased breeding success in an urban population of near-threatened African Crowned Eagles (Stephanoaetus coronatus)

Colleen Downs, Shane McPherson, Rebecca Muller, Petra Sumasgutner & Arjun Amar
Urban areas can be attractive to certain species because of increased food abundance and nesting availability which in turn may increase productivity or breeding rates. However, there are also potential costs associated with urban living such as higher nest failure, poorer body condition or increased prevalence of disease. These costs may result in species trading off the number of young produced against the condition of their young. African Crowned Eagles (Stephanoaetus coronatus) are a rare...

Khayelitsha Mitchell's Plain Survey 2000

Cape Area Study 2005

Sustainable Cities Survey 2018, Luanda

Sylvia Croese

Thermal properties and segregation behaviour of Pt nanowires modified with Au, Ag and Pd atoms: A Classical Molecular Dynamics Study - data

Thobani G Gambu, Umberto Terranova, David Santos-Carballal, Melissa A Petersen, Glenn Jones, Eric Van Steen & Nora H De Leeuw
The thermal properties of bimetallic Pt nanowires have been investigated using classical interatomic potentials. Edge decorated Pt nanowires may improve the inter-facet exchange of reaction intermediates resulting in improved oxygen reduction reaction activities at fuel call cathode electrodes. In this work we report on the melting behaviour of Pt-based nanowires where either an edge atomic row or atomic shell of Pt nanowires are substituted by Au, Ag or Pd. Our overall intention is to find...

Data from: Cretaceous origins of the vibrotactile bill-tip organ in birds

Carla Du Toit, Anusuya Chinsamy & Susan Cunningham
Some probe-foraging birds locate their buried prey by detecting mechanical vibrations in the substrate using a specialised tactile bill-tip organ comprising mechanoreceptors embedded in densely clustered pits in the bone at the tip of their beak. This remarkable sensory modality is known as “remote-touch”, and the associated bill-tip organ is found in probe-foraging taxa belonging to both the paleognathous (in kiwi) and neognathous (in ibises and shorebirds) clades of modern birds. Intriguingly, a structurally similar...

Lack of vulnerability segmentation among woody species in a diverse dry sclerophyll woodland community

Chris Smith-Martin, Robert Paul Skelton, Kate Johnson, Christopher Lucani & Tim Brodribb
1. Recent findings suggest that tree mortality and post-drought recovery of gas exchange can be predicted from loss of function within the water transport system. Understanding the susceptibility of plants to hydraulic damage requires knowledge about the vulnerability of different plant organs to stress-induced hydraulic dysfunction. This is particularly important in the context of vulnerability segmentation between plant tissues which is believed to protect more energetically “costly” tissues, such as woody stems, by sacrificing “cheaper”...

Cape Town RSC Levy Firm Panel Data 2000-2006

Kerr, Andrew

SALDRU Newspaper Clippings Collection

Numerical Analysis of the Transient and Non-Isothermal Channel Flow of a Third-Grade Fluid with Convective Cooling

Tiri CHINYOKA & Oluwole Daniel MAKINDE
We investigate the unsteady, non-isothermal, pressure driven channel flow of a third grade liquid subject to exothermic reactions. We assume temperature dependent fluid viscosity and also that the flow is subjected to convective cooling at the channel walls. The exothermic reactions are modelled via Arrhenius kinetics and the convective heat exchange with the ambient at the channel walls follows Newton’s law of cooling. The time-dependent, coupled, and nonlinear partial differential equations governing the flow and...

Data from: The role of browsers in maintaining the openness of savanna grazing lawns

Michael Voysey, Michelle Greve, Sally Archibald, William Bond, Carla Staver & Jason Donaldson
1. In savannas, ruminant herbivores can have divergent impacts on tree recruitment and resulting woody cover. Heavy grazing by cattle results in woody thickening, whereas intensive grazing by wildlife instead tends to be associated with lower woody cover. 2. To disentangle why woody cover is low in areas heavily grazed by wildlife, we tested (I) whether short-grass environments attract indigenous mammalian browsers; (II) whether preference for short grass decreases with browser body mass because of...

Madagascan highlands: originally woodland and forest containing endemic grasses, not grazing-adapted grassland

Grant Joseph & Colleen Seymour
Long considered a consequence of anthropogenic agropastoralism, the origin of Madagascar’s central highland grassland is hotly disputed. Arguments that ancient endemic grasses formed grassland maintained by extinct grazers and fire have been persuasive. Consequent calls to repeal fire-suppression legislation, burn protected areas, and accept pastoralism as the ‘salvation’ of endemic grasses mount, even as the IUCN declares 98% of lemurs face extinction through fire-driven deforestation. By analysing grass data from contemporary studies, and assessing endemic...

Registration Year

  • 2020
    36

Resource Types

  • Dataset
    34
  • Collection
    1
  • Data Paper
    1

Affiliations

  • University of Cape Town
    36
  • Stellenbosch University
    3
  • University of Vienna
    2
  • University of New Mexico
    2
  • University of La Réunion
    1
  • University of Oviedo
    1
  • University of Montana
    1
  • University of Washington
    1
  • Stanford University
    1
  • University of Pretoria
    1