The environmental impacts of solar power generation and particularly Concentrated Solar Power (CSP) are not well understood. There have been reports of birds injured and killed by concentrated solar radiation at power 'towers' and from collisions with mirrors at both tower and 'trough' facilities. This study assesses the impacts of a utility-scale 50 MW 'trough' CSP facility - Bokpoort CSP Power Plant - in the Northern Cape, South Africa. To assess the changes in functional and structural changes in bird communities, bird counts in the solar fields (mirror arrays) were compared with transects from rangelands adjacent to the CSP plant. Invertebrates were sampled with sticky and pitfall traps adjacent to the power block, in the solar fields, and in the rangeland landscape to assess changes in invertebrate communities. There were significant changes in bird distribution across the landscape with more species richness and two orders of magnitude greater abundance in the rangeland compared to the solar fields. Fewer invertebrates were caught, but with a greater taxonomic richness in rangeland compared to the power block and solar field. The facilities' evaporation ponds created novel wetland habitat for birds; 23 species were recorded that would have been absent from the area prior to construction, including three breeding species. The solar fields were surveyed for bird injuries or fatalities over 3 months; only eight dead birds were found, all but one was too old to determine the cause of death (>1 month); the remaining carcass likely died from a mirror impact. Western Barn Owls (Tyto alba) made up half of the mortalities. Biases in mortality estimates due to searcher efficiency and scavenger removal were substantial only for small birds. Twenty-one animals (3 reptiles, 12 mammals, 6 birds) likely drowned in the evaporation ponds after being unable to escape. The recorded mortalities were very low in comparison with similar studies on CSP facilities. No threatened or endangered species were killed. Overall, the facility had a low impact on bird populations, but the drowning risk posed to animals by evaporation ponds requires mitigation. The negative impacts observed could be minimised through careful site selection of solar facilities and careful design and mitigation considerations particularly with regard to evaporation and water ponds in arid areas such as the Northern Cape.

Nest predation is one of the principle constraints on bird breeding success, accounting for 20 to 80% of all nest failures. It can be exacerbated by anthropogenic factors and the resultant increased predation pressure has caused the decline of numerous bird species worldwide. Identifying management strategies to reduce nest predation is consequently a priority for biodiversity conservation. Many lethal and non-lethal methods of predator control can be ineffective, unethical, time-consuming and expensive to implement. An alternative is the use of Conditioned Food Aversion (CFA), a method by which animals are deliberately induced to avoid nests following consumption of eggs treated with an illness-inducing toxin. Previous studies suggest that this technique is effective but many have been subject to several methodological flaws that limit their applicability. Here I employ an improved experimental design that uses both spatial and temporal controls and incorporates quantification of predator identity and abundance. By so doing the resultant effects can be attributed to CFA treatment with higher certainty. In the Berg River Estuary, South Africa, nest losses of the Kittlitz's Plover (Charadrius pecuarius) are high due to Pied Crow (Corvus albus) nest predation. I used this common plover as a model species to test whether CFA can be used as a conservation management tool to reduce nest predation. I used a field experiment to assess whether provisioning quail eggs treated with carbachol, an illness-inducing chemical, resulted in reduced nest predation. To assess the effects of treatment, nest survival data for both artificial plover nests containing quail eggs and natural Kittlitz's plover nests, as well as predator abundance were compared across three experimental phases (pre-treatment, treatment and post-treatment) and according to treatment type (carbachol versus water).

Little is currently known about the spatial ecology of the endangered African penguin during the non-breeding season. As foraging success during this period is critical to adult survival, this project explores their dispersal patterns, as well as the degree of overlap with commercial purse-seine fisheries which target the same prey. African penguins from two colonies (Bird Island, Algoa Bay, south coast and Dassen Island, west coast) were tracked over 3 non-breeding seasons using Platform Terminal Transmitters and Global Positioning System devices to explore their pre- and post-moult dispersal patterns. Dispersal trips varied greatly between individuals, but there were still significant differences in the dispersal patterns found between islands and between life history-stages at Dassen Island. Bird Island penguins tended to make frequent, short trips, returning to their breeding colony in between, whereas Dassen Island penguins followed one of two strategies: either making few (up to 3) very long trips (up to 4000km), or adopting a central-place foraging pattern based at a point along the coast, distant from their breeding colony. At Dassen Island a clear spatial divide is evident with most pre-moulters dispersing south whereas most post-moult birds dispersed north, off the west coast. Bird Island penguins all moulted at their breeding colony and seldom visited either the adjacent coastline or other islands. During pre-moult, Dassen Island birds often spent nights close to shore along the coast or at other colonies and about a quarter of them moulted at another colony, most often at Stony Point, on the mainland east of Cape Point. Five dispersal patterns (defined in terms of the direction and distance of the furthest point reached) were identified for birds from Dassen Island and there is some indication that different dispersal patterns have distinct survival implications. Over 60% of PTT loss (a proxy for penguin mortality) occurred in a small area in the northern part of St Helena Bay, offshore from Lambert's Bay and Strandfontein and could be due to high levels of seal predation, which has been previously documented in the area. Commercial small pelagic fishing data were analysed over three years (2012-2014). Average fishing effort decreased each month from September to December (when hardly any fishing occurred in any of the three years) and there was much greater fishing effort along the west coast than on the south coast. Commercial fishing effort was compared to penguin track data to assess the degree of potential overlap between these two pelagic predators. Firstly, the spatial overlap between core penguin non-breeding dispersal areas and core fishing areas was assessed on a broad temporal scale (three years). Bird Island penguins were found to be more spatially removed from fishing activity with no overlap in core fishing and dispersal areas on the south coast. Compared to the size of their dispersal area, Dassen Island penguins which stayed along the lower west coast showed the highest overlap with core fishing areas. The two most common dispersal patterns exhibited by Dassen Island penguins both involve journeying to areas outside the range of purse-seine fishing, indicating the possibility of avoidance behaviour once the pressures of breeding are lifted. Direct (daily) overlap between commercial fishing effort and penguin tracks was studied although the low frequency of the penguin position data restricted the analysis to a 20 km scale. The results were similar to those described above, with most direct overlap occurring between Dassen Island and Gansbaai.

Includes bibliography. / This study aimed to describe patterns of distribution in terrestrial Afrotropical birds, to investigate the causes of these patterns, and examine how aspects of distributional patterns may be used to prioritize local regions for conservation attention. Presence-only data were gathered and digitized at one-degree square scale for 1686 terrestrial bird species that breed on or regularly visit sub-Saharan Africa as non-breeding migrants. Biogeographical analysis of the 1437 species that are globally restricted to sub-Saharan Africa (Afrotropical endemics) revealed a suite of geographical areas that have a homogenous and characteristic avifaunal composition, termed avifaunal zones. The approach used in this study ensured representativeness in the resultant biogeographical classification scheme, which was not biased towards avifaunas that are species rich or that contain many narrow endemics, and further included avifaunas that consisted of few, but taxonomically and ecologically distinct species (e.g. the Namib Province). Analysis of zonal boundaries exhibiting high levels of turnover, defined specifically as species replacement, were distinguished from zonal boundaries that are characterised by species richness gradients. For instance, the northern forest-savanna boundary between the Guineo-Congolian and Northern Savanna Subregions was shown to consist of a sharp ecotone between forest and savanna, whereas the boundary between the Northern Savanna and Northern Arid Subregions was shown to be dominated by species drop-outs. This shows that whereas the Northern Savanna Subregion represents a unique avifauna that is distinct from that of the Guineo-Congolian Subregion, the Northern Arid Subregion is merely a depauparate subset of the Northern Savanna avifauna. Patterns of species richness and narrow endemism where shown to differ between species groups that exhibit different life history characteristics (e.g. residents vs. migrants) and distributional characteristics Atrotropical endemics vs. nonendemics). Differences can probably be attributed to island biogeography and aerography theory.

The use of poison by farmers to control livestock predators is a major threat to vulture populations across Africa. In Namibia, there is now some understanding of poison use on commercial farms, but the situation in the communal farmlands is still poorly understood. Using a series of 36 questions, I interviewed 367 communal farmers to assess the prevalence of poison use across the north-west, north and eastern communal land. I found that 18% (SE 2.8) of farmers had killed a predator in the last year and 1.7% (SE 2.1) used poison to do so. I mapped the probability of poison use across the communal regions surveyed and found that poison use is predicted to be higher (up to 7% of farmers using poison) in some areas of the upper north-west. In contrast to previous research, those living adjacent to protected areas did not experience greater losses to predators and as a result were not more inclined to use poison. I found that those using poison are more likely to own greater numbers of livestock, particularly large livestock. Overall, my study suggests that poison use is approximately 12 times lower in the communal areas than on commercial farms. A number of farmers expressed that it is dangerous to use poison on communal land as the risk of non-target impacts is much higher where the land is not fenced and is communally used. Nonetheless there are communal farmers who are using poison and this poses a risk to already threatened vulture populations. Lastly, I did a survey to look at the farmers' local knowledge about vultures, their attitudes towards them and any cultural value that vultures hold. Overall vultures were viewed positively by farmers. The cultural use of vulture parts appeared fairly uncommon, with 9.5% of farmers reporting that they knew of uses. Many farmers indicated that the cultural use of vulture parts was something practiced by previous generations. Feathers were the most commonly used part, mainly for decorations and making arrows. From my assessment, it appears that anthropogenic threats to vultures in communal areas are fairly low. The cultural use of vulture body parts is rare. In addition, poison is used but this practice is not nearly as common as it is on commercial farms. Since poison can have such devastating impacts on vulture populations, I nonetheless advise that reactive and preventative measures are put in place to reduce poisoning and minimise the impact when poison is used. The identified 'hotspots' of poison use will assist local authorities to focus their poison mitigation efforts.

Southern Ground-Hornbills Bucorvus leadbeateri are listed as Endangered in South Africa and there is a concerted effort to reverse their population decline. Understanding the factors affecting their movement patterns and how they interact with their habitat is useful to inform conservation and habitat management options for the species, to select sites for artificial nests and to identify suitable areas for reintroduction initiatives. In this study, I report daily and seasonal patterns of habitat use as well as patterns of roost site use of four Southern Ground-Hornbill groups in the Associated Private Nature Reserves, northeast South Africa, based on data from GPS-satellite tags collected over one year from October 2010 to September 2011. Home ranges varied from 5.9-10.3 km² and were larger in winter than during the summer breeding season. Daily travel distances were greater during the breeding season, when birds were constrained to forage close to their nest, and were lower in winter, when birds ranged more widely. Hourly travel distances were affected by time of day, season, air temperature and group. Birds travelled farthest per hour in the morning, decreasing in the afternoon in winter. However, in summer hourly travel distances were bimodally distributed, with a minimum during the middle of the day when ambient temperatures exceed 25⁰C. Acacia-dominated vegetation and riparian habitats were favoured disproportionately during the heat of the day in summer, presumably because they offer more shade than other habitats. The number of roost sites used per month decreased progressively throughout the Early Wet season (October-December) and was lowest during the Late Wet season (January-March) for three groups that bred successfully. Mean monthly nights per roost were highest for these groups in the Early Wet and Late Wet seasons, specifically over December and January, coinciding with the peak breeding period. Throughout the Early Wet season, all four groups frequently roosted in close proximity to the nest, with 54-83% of roosts being within 1 000 m of the nest. During the Wet season, riparian habitats were favoured for roosting by the three groups that bred successfully, while during the dry season, disturbed areas, combretum-dominated habitats and mopane-dominated habitats were used. I conclude that the optimal habitat configurations for ground-hornbills include a mosaic of habitat types, including open areas for foraging and dense trees for shade as well as adequate large trees for nesting and roosting, particularly in riparian habitats.

As trends in urbanisation continue globally, there is a growing need to understand the impacts of urban development on wildlife. Whilst urban impacts on patterns of diversity and abundance of species have been well-studied, there remains a distinct lack of understanding around the impacts on ecological interactions. Different species have different levels of tolerance to urban disturbance, some species even appear to thrive in urban areas and make use of human-subsidised resources; but the physiological costs and trade-offs faced by urban-dwelling species are poorly understood. Given that their range in South Africa has only recently expanded into the human-dominated landscapes of the Western Cape, the Black Sparrowhawk (Accipiter melanoleucus) provides an excellent opportunity to explore some of these questions. In this study we explored how urbanisation may affect the health of this raptor on the Cape Peninsula, South Africa. If the health of this species is negatively influenced by levels of urbanisation, this might be driven by differences in diet and prey availability across the urban spectrum. Thus, we explored this potential mechanism by examining diet composition and assessing prey abundance within different territories and habitat types. The health of nestling Black Sparrowhawks was evaluated through their immune response (Heterophil/Lymphocyte ratio in white blood cell counts), body condition (based on morphometric measurements) and blood parasite infection (presence and abundance of Haemoproteus and Leucocytozoon). Trends in diet composition along a gradient of urban cover were determined through the analysis of prey remains collected in the immediate nest surroundings and differences in prey abundance were determined through point counts in different habitat types.

Abstract The Rudd's Lark Heteromirafra ruddi is a globally threatened species with a fragmented population occurring in one of the world's most poorly-protected biomes, the grasslands. This, together with its endemism to the Highveld of South Africa and climate envelope modelling which predicts a dramatic reduction in its available habitat, places the species firmly in the cross-hairs of extinction risk. This thesis aims to gain a better understanding of Rudd's Lark population trends, habitat preference and threats in one of its most important remaining core sites in the grasslands around Wakkerstroom, Mpumalanga Province, which are under private ownership and used predominantly for grazing. My objectives were, first, to determine whether the species has declined in the Wakkerstroom area since a survey conducted in 2002 by David Maphisa. Second, to determine what habitat variables predict Rudd's Lark incidence, whether there has been a change in its available habitat and in farm management practices, and whether the species has changed in its habitat selection since the previous survey. Finally, I aimed to investigate whether other grassland birds (particularly other threatened grassland endemics) also respond to fine-scale habitat variation and share habitat preference with the Rudd's Lark. I found both absolute lower numbers of Rudd's Larks (5 transects with Rudd's Lark present down from 9 in 2002; 9 individuals down from 32), and a lower probability of encounter (significantly lower in the case of individuals). Seven transects had been lost to crop production, two of which formerly contained Rudd's Larks. Forb and dead vegetation cover had significantly increased at a coarse scale, but vegetation variables did not explain any significant variation in Rudd's Lark incidence at either a fine or a coarse scale within 2016. However, Rudd's Larks appear to be occupying subtly different habitat now compared to 12 years ago: lark territories surveyed in 2016 had less bare ground and more but shorter grass cover than in 2002. Most farmers reported warmer conditions in recent years and that burning generally took place between August and October, matching the analysis of remotely-sensed fire data from the past ten years and implying that destructive late-season fires are not common. Correspondingly, I found that burning regimes did not predict Rudd's Lark incidence. Among other threatened grassland species, Yellow-breasted Pipits showed a clear preference for taller grass and higher altitudes, unlike Rudd's Larks which showed no detectable preferences. In summary, direct loss of grassland habitat through conversion to crops appears to be a pressing threat to Rudd's Larks, although the species has also declined within the remaining area of grassland habitat. The specific drivers of this decline remain unclear given that the observed changes in grassland structure since 2002 do not correspond with Rudd's Lark habitat selection. Taken together, these findings are very concerning given that the Wakkerstroom area is considered to be one of the last remaining core sites for the species, and call its IUCN threat status of globally Vulnerable into question. A priority for future research will be to understand what limits Rudd's Larks to its current pockets of occupancy within its remaining apparently suitable grassland habitat, and whether increasing grassland fragmentation will accelerate its decline. Key words: fire, grassland, habitat selection, Heteromirafra ruddi, IUCN status, rangelands, Rudd's Lark, threatened species, transects

Global average temperatures are predicted to increase by as much as 5ᵒC by 2100. Therefore, it is imperative to identify how species are affected by temperature increase to ensure that proper conservation and management of wildlife can be implemented. Species which already live in warmer climates, such as deserts, may provide the first clues to the impacts of increasing temperatures. Birds represent an ideal indicator because research has shown that rising temperatures affect their behaviour, including foraging and provisioning of young, thereby reducing reproductive success. However, it remains unclear whether this results from physiological constraints on behaviour, from declining food availability and or access to prey items at high temperatures. In this study, I aimed to identify how temperature affects the foraging and provisioning behaviour of wild Fork-tailed Drongos, Dicrurus adsimilis, when supplemental food is provided. Additionally, I aimed to identify how nestling growth rates change with temperature. The results of two supplemental feeding experiments indicated that as temperatures increased, adults significantly reduced their willingness to forage, reduced provisioning to offspring and exhibited increased rates of heat dissipation behaviour. Furthermore, when provisioning nestlings, adult drongos consumed a larger proportion of supplementary food at higher air temperatures, and provisioned less. This suggests that they suffer greater provisioning costs at such times. Surprisingly, despite finding several negative effects of temperatures on adults' willingness to forage and provisioning, there was only a weak and non-significant effect of temperature on nestling growth rates. This suggests that adults may be able to compensate for reduced foraging at high temperatures. My study shows that the increased thermoregulatory costs of activity at high temperatures can constrain foraging and provisioning, even when food remains abundant. However, whether this impacts the fitness of current offspring or parents future reproductive success remains unclear.

Includes bibliographical references. / I studied a long-term data set for Wandering Albatrosses Diomedea exulans collected at sub-Antarctic Marion Island to investigate adult survival, breeding biology and factors affecting reproductive success of this long-lived pelagic seabird. Until recently, the complex adult life cycle has caused biases in conventional mark-recapture modelling analyses that assume that recapture probability is equal for 'observable' and 'unobservable' states of the biennial adult life cycle. During 'sabbaticals' taken after successful and late-failed breeding attempts, the chances of resighting an adult Wandering Albatrosses are reduced, thus affecting estimated recapture rates. I applied a multi-state mark-recapture method to the colony breeding data from Marion Island (1987-2005). This method allows individual albatrosses to move through a network of breeding states according to previous breeding history using transition probabilities to estimate survival, breeding and breeding success probability. The best fit models in the multi-state analysis were those representing constant survival and independent breeding probabilities, suggesting that Wandering Albatrosses constrain reproductive investment to ensure long-term survival. I used the parameter estimates in a transition matrix to calculate the steady state equilibrium for the Wandering Albatross breeding population. For the first time I was able to estimate that approximately 3000 pairs of Wandering Albatrosses use Marion Island for nesting. I also describe the effects of age, sex and experience on Wandering Albatross reproductive success. Birds that were most successful began breeding at the mean age of first breeding and older and younger birds were less successful in 5/10 year periods after the onset of breeding. Disappearance from the population decreased with an increase of age of first breeding. I tested the selection and experience hypotheses on birds with 'complete' histories defined according to an imposed rule on recovery data. Males appeared to increase breeding success as a result of selective removal of low-quality individuals from the population (the selection hypothesis), whereas females appeared to improve their breeding success as a result of increased experience.