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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Essays in Environmental and Applied Economics

Forge, Fabien 18 December 2020 (has links)
This dissertation includes three distinct chapters looking at different challenges faced by developing countries. The first chapter examines the situation of farmers under climate change by mapping future climatic conditions onto the distribution of agricultural revenue in India. The second chapter uses the Mexican conditional cash transfer (CCT) program Progresa to investigate the relationship between income, education and fertility. Finally, the third chapter studies the extent to which preferential tariffs extended by OECD countries have helped least developing countries (LDC) diversify their exports. Given the issues explored by these essays, I contribute to several distinct strands of the economic literature, yet each paper is motivated by its policy relevance and is embedded in the issues faced by developing economies.
82

An analysis of vegetation pattern and its relationship to NDVI data in the Namaqualand area, South Africa

Fox, Sarah-Jane Caroline 23 February 2017 (has links)
The Namaqualand area in the North Western Cape, South Africa is unique in comparison to other similar semi-arid areas of the world. It has a high biodiversity and endemism and is consequently an area of interest for a growing number of conservation initiatives. Climate plays an important role in influencing the phenology and growth of the vegetation in the area. Remote sensing techniques were used to reveal the vegetation patterns in the greater Namaqualand area and to relate them to climatic variables. To do this we used the normalised difference vegetation index (NDVI) to relate biomass to altitude, rainfall and vegetation type. Each vegetation type in the area had a unique temporal signature and the climatic variables influencing the summer rainfall and winter rainfall vegetation types differed significantly from each other. Mean annual NDVI was significantly correlated to precipitation and potential evapotranspiration (PET) (r = 0.60, -0.63 respectively). A multiple regression model explained 52% of the variance when Mean Annual NDVI was related to climatic variables. Mean NDVI in August (the month of maximum NDVI in most of Namaqualand) was significantly related to PET and the current plus two previous months of precipitation (r = -0.72 and 0.74 respectively). A multiple regression model for mean NDVI in August and climatic variables explained almost 58% of the variance. The results suggest that NDVI can be used successfully as a measure of growth and phenology in the Namaqualand area and that NDVI could be used in climate models, drought prediction, desertification predictions and a number of other applications in the future.
83

Climate change and wildlife utilization on private land: evidence from wildlife ranching in South Africa

Otieno, Jackson Ongong'a January 2016 (has links)
This thesis focuses on the economics of climate change and wildlife utilization in privately owned parcels of land in South Africa. A significant proportion of agricultural land in the Southern Africa region has undergone transition with many farmers opting to move away from livestock farming to either wildlife farming, ranching or conservancies. In other instances, farmers in areas which were predominantly under irrigation are also switching to wildlife land use. One of the biggest claims to this transition has been the effects of climate change on livestock and crop production. The increasing cost of production associated with worsening climate continue to force farmers into abandoning livestock and crop production in favor of wildlife, which has been considered more profitable in the marginal areas in the southern Africa region. However, several uncertainties engulf wildlife utilization on private land, this may hinder its ability to bring about development that might improve the welfare of the communities and those individuals who directly participate in wildlife conservation in the private areas. The most pressing issue in wildlife utilization on private land includes; i). Its effects on the welfare of the communities living around the wildlife farms, ranches or conservancies. The livelihood of these communities revolved around livestock and livestock production for employment, food provision and other socioeconomic and cultural provisions. Therefore, the transition from livestock to wildlife production inevitably can improve or worsen the living standards of these communities, ii). Sustainability of wildlife production as alternative land use in the face of prevailing and future climate scenarios. While it has been cited that wildlife and wildlife revenues are more resilient to climate change, there is every indication that climate change affects wildlife conservation, iii). The role of wildlife in climate change adaptation. Farmers in South Africa are known to mix wildlife with livestock as one way of adapting to climate change. Over time, such farms have transited into wildlife ranches. The issue therefore is how vulnerable are wildlife ranches compared to livestock and mixed wildlife-livestock ranches?
84

How has environmental violence been experienced during the Cape Town water crisis using the Newlands Spring as a case-study

Swain, Meagen Courtney 24 February 2020 (has links)
Four million residents of a major modern city faced the very likely existential and physical threat of running out of water. The water crisis continues to be an extremely complex threat with many complicated aspects to the drought, which resulted in residents of Cape Town reacting with intensity to this danger. The crisis is an example of how ignoring environmental issues can lead to catastrophic outcomes for society. For South Africa, which is characterized by a turbulent history, Homer-Dixon (1999) predicted there would be violent conflict in the future over resource scarcities. The drought was not a shock, it was a stress; what the drought fashioned were instances of shock which mostly related to the media campaign for Day Zero. Although no violent conflict on a mass scale has transpired as a result of the ongoing water crisis, there have been cases of civil violence. From protests at the greater Cape Town scale to physical altercations witnessed at Newlands Spring, the results of the present study demonstrate that mass violent conflict is not a far-off consequence of water scarcity. This research aimed to determine whether environmental violence was a lived experience for the residents of Cape Town due to the water crisis. One of the objectives was to understand whether the water crisis-induced feeling of distress and anxiety and whether indicators of slow violence and “Solastalgia” could be identified; a concept put forth to provide clarity to distresses which are environmentally caused (Albrecht et al., 2007; Higginbotham et al., 2007). Over the course of October 2018, semi-structured interviews were conducted with security and informal workers and a public survey was conducted with 100 residents who collect water at the Newlands Spring. The outcomes observed in this research is that when people feel as though their security is threatened, people tend to respond violently to the scarcity of a vital resource. The key finding of this study is that environmental violence was experienced over the crisis period. This leads to the conclusion that Solastalgia was likely to be experienced by those engaging within this Newlands Spring environment and elsewhere. The Structural violence and Supply induced violence have meant that people across South Africa experience water crises of different scales. Climate change is to aggravate these existing forms of violence and produce more complex psychological, social and economic impacts on those affected by water scarcity. Furthermore, this research contributes to the knowledge that droughts and water scarcity pose immeasurable threats to humanity.
85

Marrying water and soil: adaptation to climate by a smallholder farmer in Zvishavane, rural Zimbabwe

Mabeza, Christopher Munyaradzi January 2016 (has links)
This thesis is a qualitative ethnographic study of innovations implemented by Mr Zephaniah Phiri Maseko, a smallholder farmer from Zvishavane, rural Zimbabwe. Ethnographic data provides insight and lessons of his practices for rethinking existing strategies for adaptation to climate change. The concept of adaptation is probed i n relationship to the closely related concepts of vulnerability, resilience and innovation. This study also explores the concept of conviviality and argues that Mr Phiri Maseko's adaptation to climate hinges on mediating barriers between local and exogenous knowledge systems. Ethnographic fieldwork aided by an analytical framework of resilience makes clear that his farming practices are informed by a realisation that dualisms are problematic. His innovations are a way of building resilience to climate change and his practices demonstrate the interdependencies in a socio - ecological system. This study argues that innovations by smallholders play a complementary role to interventions by outsiders in the discourse of adaptation to climate in the drylands of southern Zimbabwe. Mr Phiri Maseko harvested water as a way of adapting to climate variability. I argue that he offered tangible adaptive climate strategies through his innovations that "marry water and soil so that it won't elope and run - off but raise a family" on his plot. His agricultural practices are anchored on the Shona concept of hurudza (an exceptionally productive farmer). This thesis explores the concept and practices of uhurudza , to suggest that the latter - day hurudza (commercial farmer) as embodied by Mr Phiri Maseko offered an important set of resources for the development of climate adaptation strategies in the region. Therefore, his activities call for a revisit of the notion of hurudza based on grain harvested, one that includes consistent income generated from selling farm produce. His innovations demonstrate elements of conviviality, resilience, accommodating local knowledge as well as ideas he learnt from various educational institutions in order to adapt to climate variability. This thesis explores the usefulness of Mr Phiri Maseko's innovations for other smallholder farmers in the Zvishavane area who have replicated it. I demonstrate that due to the success of his innovations, uptake has been high underpinning the fact that these smallholders appear to be managing to adapt to climate variability. This ethnographic study of smallholder farmers' adoption of innovations to climate highlights the "complex interplay" of multiple factors that act as barriers to uptake. Such interplay of multiple stressors increases the vulnerability of smallholders. I conclude by arguing that in as much as the skewed colonial land policy impoverished the smallholder farmers, Mr Phiri Maseko nonetheless redefined himself as a latter - day hurudza and thus breaks free from the poverty cycle by 'conjuring ingenious' ways of reducing vulnerability to climate. I do not suggest that his innovations offer a 'silver bullet' solution to the insecure rural livelihoods of smallholder farmers; nevertheless, they are a source of hope in an environment of uncertainty.
86

The use of traditional weather forecasting by agro-pastoralists of different social groups in Bobirwa sub-district, Botswana

Mosime, Bonolo 14 February 2019 (has links)
Agro-pastoralists of Bobirwa sub-district depend mainly on rain-fed agriculture as a source of their livelihood. However, this agro-pastoralism is affected by climatic variability. Advanced warning of upcoming weather information is, therefore, important in informing farming decisions. Traditional weather forecasting is often a major planning tool used to inform agro-pastoralists’ decision making and has been handed from one generation to another. For instance, local knowledge indicators are used to determine onset of rainfall and quality of the rainfall expected. However, there are numerous factors that may have affected the effective use of and dependence on traditional weather forecasting over the years. For this reason, it is critical to examine the current state and use of traditional weather forecasting among the agro-pastoralists. This thesis describes the traditional weather forecasting that agro-pastoralists in Bobirwa sub-district Botswana hold and use in planning for agricultural activities to cope with climate variability. It also examines changes that have been observed in the use of traditional weather forecasting over time. By exploring the knowledge used to generate early warning systems and coping strategies to climate variability of agro-pastoralists, we examine underlying vulnerabilities and resilience possibilities. Data was collected through purposively selecting a total of 101 agro-pastoralists who were further stratified by age and gender. The following qualitative techniques were used in data collection: semi-structured interviews (54 interviewees constituting 37 forecasters and 17 non-forecasters), focus group discussions (47 participants consisting of between 4 and 12 participants), and key informant interviews (11 forecasters who use multiple indicators). The snowballing technique was the main sampling strategy. Knowledgeable traditional forecasters in FGD’s were used to identify key informants with whom semi-structured interviews were conducted. All data was analysed using the thematic analysis method. Data was constructed using a cyclical process to generate themes which consisted of the initialisation (capturing participants’ accounts), construction of themes, relating the themes and developing results. From the study, it was found that male and female elderly agro-pastoralists in Bobirwa are more knowledgeable about traditional weather forecasting and use the traditional weather forecasting techniques to inform their decisions, while the less-knowledgeable adults and youth expressed having limited use of traditional weather forecasting in decision making. There were also differences in the use of specific traditional indicators based on the positionality of an individual in the society as well as age and gender. While the participants indicated that traditional weather forecasting is a reliable technique, climate change is believed to have resulted in unpredictable trends in recent years. For example, excessive floods, patchy and reduced rainfall, extensive heat spells with no specific patterns, changes in biological indicators, and thus, present a challenge to these agro-pastoralists. In all, traditional weather forecasting remains a cultural artefact in the community and will always be practised by the agro-pastoralists. However, many elements threaten the existence of the traditional weather forecasting such as the death of custodians of knowledge, the disruptive nature of climate change, youth migration to cities and the ubiquity of modern practices. Further to this, the prevalence of modern practices, for example Christianity, is transforming the use and beliefs of individuals in traditional weather forecasting leading to reduced intergenerational transfers of the traditional weather forecasting. It is prudent to expect that as cultural practices change within societies, cognisant of the fact that culture is dynamic, it is also expected that the use of traditional weather forecasting will change. It should, however, not be construed that the changes in the use of traditional weather and seasonal forecasting are an indication of the unreliability of traditional indicators, but inability of individuals to forecast. In turn, the study recommends the conservation of the traditional weather forecasting and traditionally important biological indicators. This can be promoted through documentation and teaching of traditional weather and seasonal forecasting techniques in conventional educational programmes. Alongside this, integration of traditional and scientific weather forecasting could be used to develop national policies to facilitate effective drought and flood coping strategies that are inclusive and aimed at limiting the traditional weather forecasting knowledge gap among agro-pastoralists of different age and gender groups. Interventions by the government can be redirected to traditional leaders or elders who bear extensive knowledge on traditional weather indicators to create awareness and facilitate knowledge exchange especially in aiding agro-pastoralists to cope with climate variability. Also, for those who are sceptical of traditional weather forecasting, the use of religious gatherings of different denominations can be an option to facilitate awareness raising of coping strategies that can be explored to reduce vulnerability amongst this group of agro-pastoralists by teaching them to adapt to the changing weather using local knowledge.
87

The distribution and population structure of Aloe pillansii in South Africa, in relation to climate and elevation

Bolus, Cosman 22 February 2017 (has links)
South Africa comprises almost 10% of known plant species and also has the only arid zone "hotspot" defined worldwide, namely the succulent Karoo. Anthropogenic climate change predictions for South Africa suggest rapid climate change in the next 50 years will have adverse effects on its vegetation biomes. This study shows how the aborescent succulent, Aloe pillansii, has a limited distribution due significantly to environmental and climatic variables and therefore it is potentially at risk given anthropogenic climate change predictions. The total South African A. pillansii population investigated is made up of 1202 individuals and is found in the Richtersveld, which is part of the Succulent Karoo. The A. pillansii individuals were sampled in terms of their height and geographical position and then defined into subpopulations by a distance of 2 kms of separation. The sub-populations were then evaluated in terms of their respective environmental and climatic variables acquired from a CCWR database for South Africa using Arc View 3.2. The sub-population size class distributions were also constructed so that population dynamics and recruitment could be investigated. The results show how the A. pillansii sub-populations are limited to a specific environmental and climatic range. The sub-populations group along similar environmental and climatic variables with the healthiest sub-populations found at lower elevation, higher temperatures and higher Potential Evapo-Transpiration. The climatic range of A. pillansii is also evident from the range of its environmental and climatic variables and the associated unhealthy sub-populations that lie on the extremes of this range. Recruitment was found to correlate strongly with the environmental and climatic variables, % winter rainfall and elevation, suggesting it is moisture limited. The evidence found in this study of A. pillansii 's specific environmental and climatic distribution may have negative implications for its future survival and conservation especially with present indications of anthropogenic climate change.
88

Climate change impact on ecosystems of Prince Edward Islands: role of oceanic mesoscale processes

Asdar, Sarah 25 July 2019 (has links)
The subantarctic Prince Edward Islands (PEIs, 47◦S-38◦E) are classified as isolated and hostile regions, in which the terrestrial and marine ecosystems are relatively simple and extremely sensitive to perturbations. The island’s location, between the Subantarctic Front (SAF) and the Polar Front (PF), bordering the Antarctic Circumpolar Current (ACC) provides an ideal natural laboratory for studying how organisms, ecological processes and ecosystems respond to a changing climate in the Southern Ocean. Recent studies have proposed that climate changes reported at the islands may correspond in time to a southward shift of the ACC and in particular of the SAF. This southward migration in the geographic position of major ocean fronts is likely to coincide with dramatic changes in the distribution of species and total productivity of this region. However, there are other sources of variability in the hydrodynamic conditions around the PEIs: upstream of the islands, at the South West Indian Ridge (SWIR), a region of high eddy kinetic activity produces mesoscale features that directly irrigate the PEIs and may impact their marine environment. Based on satellite altimetry in that region, the positions of the SAF and PF were found to be highly variable at interannual and monthly time scales. They also revealed a significant long-term southward trend which was highlighted at the Southern Ocean scale. The mesoscale activity also showed an interannual and intra-annual variability and a decrease in eddy kinetic energy over 24 years was observed in the region. At a more local scale, we highlighted that the archipelago’s environment was impacted by the mesoscale features produced at the SWIR. The temperature, the mixed layer and velocities recorded between the islands were clearly affected by the eddies passing in the vicinity of the PEIs. Moreover, a large signal dominating the main current time series appeared to be a tidal signal, another important driver of variability of the circulation in between the two islands. On a second hand, an idealised model configuration was designed for the PEIs region to study the mesoscale eddy properties and the physical mechanisms of their formation at the ridge. The Eddy Available Potential Energy revealed a maximum of energy around 800 m depth, confirming the deep reaching characteristic of the eddy originated in the region and suggested the presence of a local energy source at this depth. This eddies activity was shown to be the result of a combination of barotropic and baroclinic instabilities occurring at the ridge. Finally, we investigated on the potential consequences of a southward shift of the SAF in the region of the islands. Because the model was idealised, it allowed us to simulate an SAF southward shift by shifting the initial and boundary conditions. The main result was the clear decrease of mesoscale activity in the region which could potentially impact the ecosystems of the PEIs.
89

Assessing the representation of teleconnective drivers of rainfall over Eastern Africa in global and regional climate models and projected future changes

Endris, Hussen Seid January 2017 (has links)
Climate variability is an important characteristic of regional climate, and a subject to significant control from teleconnections. An extended diagnosis of the capacity of climate models to represent remote controls of regional climate (teleconnections) is vital for assessing model-based predictions of climate variability, understanding uncertainty in climate projections and model development. An important driver of climate variability for Africa is the sea surface temperature (SST) - rainfall teleconnection, such as the El Ni˜no/Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD). In this study, an assessment of the teleconnection between tropical SSTs and Eastern African rainfall in global and regional climate models is presented, with particular attention paid to the propagation of large-scale teleconnection signals (as represented by model reanalyses and Coupled Global Climate models (CGCMs)) into the domain of the Regional Climate Models (RCMs). The teleconnection-rainfall relationship with the Eastern Africa region is assessed in two rainfall seasons (June-July-August-September and October-November- December) under present and future periods. Evaluation runs (RCMs driven by reanalysis datasets) and historical simulations (RCMs driven by CGCMs) are assessed to quantify the ability of the models to capture the teleconnection relationship. The future analysis is performed for two Representative Concentration Pathway scenarios (RCP4.5 and RCP8.5) to assess future change in this relationship as a result of global warming. Using ERA-interim reanalysis as perfect boundary conditions, the RCMs adequately simulate the spatial and temporal distribution of rainfall in comparison with observations, although the model performance varies locally and seasonally within the region. Furthermore, the RCMs correctly capture the magnitude and spatial extent regional-scale seasonal rainfall anomalies associated with large-scale oceanic modes (ENSO and IOD). When the lateral boundary conditions are provided by CGCMs, RCMs barely capture the regional teleconnection patterns associated with large-scale modes, and mostly depend on the selection of the driving CGCM. Comparison of the CGCM-driven RCM simulations with the reanalysis-driven RCM simulations revealed that most of the errors in teleconnection found in the RCM simulations are inherited from the host CGCMs. The ERA-Interim driven downscaled results show better agreement with observed spatial teleconnection patterns than the CGCM driven downscaled results. Analysis of the CGCMs and corresponding downscaled results showed that in most cases both the CGCM and the corresponding downscaled simulations had similar teleconnection patterns, but in some cases the RCM results diverge to those of the driving CGCM results. It has been demonstrated that similarities in SST-rainfall teleconnection patterns between the RCM simulations and respective driving CGCM simulations are noted over the equatorial and southern part of the region during OND season, where the rainfall is primarily controlled by large-scale (synoptic-scale) features, with the RCMs maintaining the overall regional patterns from the forcing models. Di↵erences in RCM simulations from corresponding driving simulations are noted mainly over northern part of the domain during JJAS, which is most likely related to mesoscale processes that are not resolved by CGCMs. Looking at the model projections of the future, although the spatial pattern of teleconnections between ENSO/IOD and rainfall still persist, important changes in the strength of the teleconnection have been found. During JJAS, ENSO is an important driver of rainfall variability in the northern parts of the region where dry anomalies are associated with El Ni˜no and wetter anomalies with La Ni˜na. Both regional and global ensemble projections show higher rainfall during La Ni˜na and lower rainfall during El Ni˜no over the northern part of the region compared to the present period. During OND, the teleconnection between ENSO/IOD and rainfall is projected to strengthen (weaken) over Eastern horn of Africa (southern parts of the region) compared to the present period. This implies heavy seasonal rains associated with positive phases of ENSO and IOD will increase in future across the Eastern horn of Africa. The change OND rainfall teleconnections are stronger and also more consistent between the models and scenarios as compared to the change in JJAS teleconnections. These findings have an important implication for the water and agricultural managers and policies in the region to tackle the anticipated droughts and floods associated anthropogenic climate change. Finally, the analysis demonstrated that the largest source of uncertainty in the regional climate model simulations in the context of teleconnective forcing of rainfall over Eastern Africa is the choice of CGCM used to force the RCMs, reinforcing the understanding that the use of a single GCM to downscale climate predictions/projections and using the downscaled product for assessment of climate change projections is insufficient. Simulations from multiple RCMs nested in more than one GCM, as is undertaken in the Coordinated Regional Downscaling Experiment (CORDEX), are needed to characterize the uncertainty and provide estimates of likely ranges of future regional climate changes.
90

Implications of climate change on the reproductive success of the Southern Yellow-billed Hornbill, Tockus leucomelas

Van de Ven, Tanja M F N January 2017 (has links)
The effects of environmental warming on the reproductive performance of birds are most easily studied in desert habitats where birds already experience air temperatures (Tₐs) close to their upper thermal tolerance. Many desert birds coincide breeding with periods of food availability triggered by rainfall during the summer season. Daily maximum air temperatures (ₘₐₓ) during the Kalahari summer season frequently reach the lower forties (°C) and recent years have been characterised by reduced rainfall and increased Tₐ. Breeding Southern Yellow-billed Hornbills (Tockus leucomelas) could be particularly vulnerable to high Tₐ due to their breeding strategy whereby the females are confined to the nest cavity for most of the nesting period. During this time their male partners are solely responsible for food provisioning, which imposes a considerable energetic demand. In this thesis, I investigated the extent to which Tₐ affects the ability and willingness of breeding males to provision their female partners and offspring. And consequently, the extent to which male investment and the thermal environment affect female body mass (Mb) and chick development rates in Southern Yellowbilled Hornbills in the Kalahari. During three consecutive hornbill breeding seasons (October - March, between 2012 and 2015), I collected life history data during 50 breeding attempts by 32 hornbill pairs. At the study site, Southern Yellow-billed Hornbills readily breed in artificial nest boxes and this allowed me to assess the internal nest climate using temperature and relative humidity loggers which were placed in most of the nests. The male hornbills in the study population were semi-habituated which facilitated behavioural observations. Weather data were recorded at an on-site weather station. Morphometric data from females and chicks were collected on a daily basis at selected nests and perch scales installed at nest entrances recorded Mb data of the provisioning males. From chick hatching to chick fledging, I observed the behaviour of the males during 30-min focal follows and focussed on foraging behaviour, prey allocation decisions (nest versus self), microsite use and thermoregulatory behaviour. Male hornbills spent more than half of their time panting at Tₐs above 34.5 °C. Days on which this threshold temperature was exceeded were therefore described as 'hot days'. The male hornbills experienced trade-offs on hot days between foraging efficiency and panting behaviour, indicating that the additional cost of thermoregulation and high Tₐ affected foraging success (Chapter 2). Males would always provision larger prey items to the nest and consumed the smaller prey items themselves. As Tₐ increased, the males increased their foraging effort, but caught fewer and smaller prey items overall, reducing the total biomass they provisioned to the nest as well as the biomass they consumed. As a result, males were unable to maintain their Mb on days when Tₐ exceeded 37.9 °C (Chapter 3). A similar effect of hot days on Mb maintenance was observed in females and chicks within the nest. Independent of chick age, females departed the nest when their Mb reached a lower limit of 189.3 ± SD 18.1 g. The females would then aid the males in nest provisioning, however the negative effect of increasing ₘₐₓ on provisioning rate was still evident; i.e. females were not able to compensate for reduced male provisioning rates on hot days. High Tₐs during the nesting period resulted in smaller and lighter fledglings and overall reduced the probability of a successful nesting attempt (Chapter 4). A thermal imaging experiment revealed that the large beak of hornbills (both males and females) plays an important role in non-evaporative heat loss. Hornbills were observed to dissipate up to 19.9 % of the total non-evaporative body heat loss via the beak. This water-saving mechanism can be highly advantageous to hornbills living in arid regions where water availability is limited (Chapter 5). Lastly, a comparison of the results of the current study with those of a study on the same hornbill population carried out between 2008 and 2011 revealed that mean ₘₐₓ as well as rainfall during the nesting period had an important impact on overall hornbill reproductive effort and success (Chapter 6). Long-lived species are expected to prioritise future reproductive opportunities over current broods. However, the predicted scenario for the Kalahari is that high Tₐs become more extreme and periods of drought become more frequent. Therefore, I predict an increased risk of breeding failure among Southern Yellow-billed Hornbills in the future which could affect the persistence of this population.

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