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An increasing incidence of mass mortalities of birds in hot deserts suggests that birds may be appropriate candidates for assessing how natural selection, under the influence of climate change, drives adaptation. ... The effects of ambient temperature on daily weight gain, foraging effort and efficiency and the presence of heat-dissipation behaviours were assessed to determine the mechanisms by which increased temperature affect babbler body condition.

Includes abstract. / Includes bibliographical references. / In the last two decades Kenyan agriculture has developed rapidly. In particular, horticultural and floricultural activities have intensified on the riparian fringe of Lake Naivasha, a RAMSAR site. The lake supports a large variety of wildlife and avifauna in particular. In the 1980s, the African Fish-Eagle (Haliaeetus vocifer) population on the lake was the densest in Africa. As a top predator resident in the Kenyan Rift Valley Lakes the African Fish-Eagle is a good indicator of general ecosystem health but is also highly susceptible to toxic effects of pesticide contamination...Globally, most organochlorine pesticides have been banned, but endosulfan, HCH and methoxychlor are widely used in Kenya, while aldrin, dieldrin and lindane are restricted and DDT, endrin, and heptachlor banned. Studies examining residue levels of these harmful chemicals in African Fish-Eagles are limited to small sample sizes examined in the 1970s and 1980s. This study is the first comprehensive investigation of organochlorine residue contamination in biological and environmental parameters from Lake Naivasha and the control water body at Lake Baringo.

Includes bibliographical references. / Several cochineal species have been used with great success for biological control of invasive cactus species, both in South Africa and elsewhere. Although most cochineal species are oligophagous, they are all exclusively associated with opuntioid cacti and therefore pose minimal risk of non-target effects in the Old World where there are no native Cactaceae. However, the ability of cochineal to use more than one host plant species has validated reports of inadvertent displacement of Dactylopius ceylonicus (the original agent released in 1913) by D. opuntiae (which was originally released on Opuntia ficus-indica in 1938) on O. monacantha in South Africa. There are also reports that the two cactus hosts, O. monacantha and O. ficus-indica, have hybridized in South Africa, but there are uncertainties as to which of the two cochineal species is associated with the alleged hybrid. The primary aim of this study was to determine the present status of D. ceylonicus and D. opuntiae on O. monacantha and on the possible hybrid. Cochineal samples were collected off cactus plants from sites in the Eastern Cape and Western Cape and identified using bioassays and morphological features. The performance of each cochineal species on each of the three cactus hosts (O. monacantha, O. ficus-indica and the hybrid) was determined through measures of female developmental rates, survival and mass at reproductive maturity. Results showed that D. ceylonicus remains present on O. monacantha at each of seven study sites, while D. opuntiae did not occur on O. monacantha at any of the sites. However, D. opuntiae is capable of establishing on O. monacantha, O. ficus-indica and the possible hybrid cactus under laboratory conditions. Dactylopius ceylonicus is also compatible with both O. monacantha and the possible hybrid, although it did not establish on O. ficus-indica. These findings showed that D. ceylonicus has not been displaced by D. opuntiae on O. monacantha in South Africa and it is expected that O. monacantha will continue to be kept under excellent biological control into the future. Results also indicated that possible hybridisation between the two Opuntia species has not produced a new taxon that is immune to either of the two control agents. However, further research is required to improve our understanding of this new plant taxon and confirm it will be suppressed by one or both of the cochineal species.

Includes bibliographical references / Human-wildlife conflicts are increasing globally and are believed to be one of the most prevalent and intractable issues that face conservation biologists today. One such conflict is found on golf courses, where high numbers of geese can come into conflict with residents and members. In South Africa, the indigenous Egyptian Goose Alopochen aegyptiaca population has increased dramatically over recent years and as a result they are often seen as nuisance animals whose population requires active management. Most non-lethal methods of goose control have had little success due to habituation to their presence, whilst the use of lethal methods are often deemed socially unacceptable. In this study we experimentally investigated the efficacy of falconry as a management tool to mitigate human-wildlife conflict. We hypothesised that the use of falconry would re-establish a landscape of fear, whereby habitat choice is influenced by the perceived fear of predation, resulting in the local departure of geese to a safer habitat, thereby reducing the population of geese to a tolerable level. Absolute counts of geese and analysis of vigilance levels were conducted at three golf courses in the Western Cape which included two control sites and a treatment site. The results of the experiment indicate that goose abundance declined by 73% at the treatment site after falconry was initiated, and that this was well over the losses due to direct predation. Vigilance levels increased by 7 6% during the treatment period, with no such changes observed at either control site. Additionally, vigilance was higher when filmed from a golf buggy compared to when filmed on foot, which may suggest the geese also learned to associate the golf buggy with the threat of predation, enhancing the overall efficacy of the falconry. While there is a relatively small lethal aspect to falconry, the results of this study confirm that a reduction in the population of geese can be achieved by simulating the naturally occurring non-lethal effects of predation that have been lost in some habitats, as a result of anthropogenic changes to the landscape. To our knowledge, this is the first truly experimental test of the efficacy of falconry to reduce nuisance birds and these important ecological findings have relevance for techniques that people deploy for dealing with human wildlife conflict, particularly where lethal options are unfavourable.

Includes bibliographical references (pages 49-58). / Subtidal reef communities in KwaZulu-Natal (KZN), South Africa are poorly known. This lack of knowledge is problematic as the biodiversity of these reefs may be severely impacted and inadequately conserved. This study documents and describes subtidal benthic communities occurring on reefs at four depth categories along the whole length of the coast. A distinct difference between northern reefs from those in the south and central parts of the province emerged with substantiating evidence of a discrete biogeographic separation at Cape St Lucia. Pairwise ANOSIM tests found no significant differences in community composition of reefs along a depth range of 10 m to 30 m at nine localities in KZN. However, differences among localities were significant at both regional (R = 0.607, P = 0.1%) and local (R = (1.792, P = 0.1%) scales. In the north, trends in species assemblages and functional groupings revealed a higher percentage cover of fauna (mainly corals) at shallower depths and a greater coverage of algae on deeper reefs. In the southern localities algae dominated shallower reefs while filter-feeding epifauna were more prevalent at deeper depths. Species richness, evenness and diversity were highest at 10m in the northern coral-dominated region while in the central/south region diversity peaked in the intermediate depth zone (15 - 25 m). Appropriate measures to conserve representative habitats in each biogeographic zone are necessary. Further research to assess biodiversity at a finer scale, as well as the establishment oflong-term monitoring to quantify natural variability and human effects, are required.

In the arid African savanna, the limited availability of water strongly affects plant productivity, but other key drivers of vegetation dynamics, such as herbivory and fire, are usually considered to have a relatively minor impact. The main purpose of this study was to characterise the spatial and temporal pattern in plant productivity in the 100 000 hectare Tswalu Kalahari Reserve (TKR) in the semi-arid Northern Cape and relate the observed changes to potential drivers using medium spatial resolution of MODIS Enhanced Vegetation Index (EVI) time series data (16 day, 250 m) from 2000 to 2015. The time series of EVI for the past 16 years in TKR presented a highly seasonal pattern which fluctuated between years. A composite of annual small integrated value of EVI images highlighted spatial and temporal heterogeneity of plant productivity in the area. The EVI value was mainly influenced by rainfall and effect of fire and herbivory was considered to be minor. These observations confirmed the extreme variability of plant productivity in the drylands in the summer rainfall region of South Africa. Additionally, most of the values concerning the phenometrics of EVI differ significantly among vegetation types. This suggests that the structure and function of the vegetation determine plant productivity as well as their being a possible effect of soil property and reflectance. The trend in plant productivity computed by residual trend analysis (RESTREND) detected a significant positive trend in plant productivity in the east and south west of TKR, which overlapped with shrub-dominated vegetation, providing evidence for possible ongoing bush encroachment in these areas. On the other hand, a negative trend was detected in some locations in the west. The data generated from MODIS EVI and the small integrated value of EVI using TIMESAT produced biologically interpretable results. However, the correlative relationship between the EVI derived from Landsat Operational Land Imager (OLI) and plant cover estimated in the field was poor or not significant and needs to be examined further.

Fencing, particularly electric fencing, is widely used across South Africa for livestock and game ranching practices. Recent studies found that leopard tortoises (Stigmochelys pardalis) are more prone to dying from electrocution along electric fences than any other taxa. However, no studies have quantified tortoise mortality along non-electric fences or assessed the impact of fence structure. With South Africa being home to more tortoise species than anywhere else in the world, thus is a conservation concern. This study quantifies tortoise mortalities associated with electrified and non-electrified fences and relates these rates to fence structure (mesh or strand). Open veld transects are used as controls to estimate background mortality. This study also reports the distribution and abundance of different fence types along 2200 km of roads in the southeastern Karoo, allowing the cumulative impacts of different fence types to be estimated. All fence types had significantly higher tortoise mortalities than open veld transects. Leopard tortoise mortalities were significantly higher along electric fences than non-electric fences. Despite forming only approximately 4% of all roadside fencing, electric fences account for 56% of leopard tortoise mortalities. This study validates concern for increased electric fence use in the future and the potential impacts on leopard tortoises. When considering the current abundance of fence types and their associated mortalities, the total number of leopard tortoise mortalities along electric and non-electric fences are similar. Angulate tortoise (Chersina angulata) mortalities were significantly higher along mesh fences than strand fences, but did not differ between electric and non-electric fences. Angulate tortoises appear to wedge themselves in mesh fences and are unable to escape. This study highlights the current threat of non-electric fencing on tortoises as no similar findings have been reported. These additional tortoise mortalities should be considered alongside other emerging threats when questioning the longevity of these tortoise populations, not only in the Karoo, but globally. The implementation and practicality of previously suggested mitigation strategies are discussed and alternative mitigation strategies are suggested. This study concludes that raising of the electric strands is impractical and the implementation of rock aprons are ineffective. Live tortoises displayed active behavior when temperature was above 20 °C, thus thermostatic switches for electric fences could potentially reduce tortoise mortalities without compromising fences function.

In an ecological context, ‘flexibility’ refers to an animal’s ability to respond immediately to environmental stimuli through physiological and behavioural adjustments. Specifically, primates exhibit a high degree of ecological flexibility, which allows them to persist through environmental changes that vary in duration and predictability. To cope with the variability of conditions within their habitats, baboons have evolved flexibility in ranging behaviour, social behaviour, and diet. Natural disasters are predicted to increase across the globe, and many parts of the world are experiencing longer wildfire seasons and higher wildfire frequencies than ever before. The aim of this study is to use an existing data set to assess how baboons responded, behaviourally and physiologically, to an extensive wildfire. I compare home range use, activity budgets, faecal glucocorticoid concentrations, and urinary C-peptide concentrations three months after the fire to the same three months in the previous year for the same 16 adult females. In the months following the fire, the baboons had a larger spatial range compared to the same months in the year prior. The additional area incorporated unburnt areas into their home range, which were preferentially used over burnt areas. Behavioural adjustments included notably less time spent engaging in social behaviours than in the year prior. Perhaps most surprisingly, postfire physiological indicators did not suggest high levels of psychological, energetic, or nutritional stress, as glucocorticoid concentrations were significantly lower post-fire compared to the year prior, while C-peptide concentrations were not significantly different between the two periods. The troop appears to have benefited from a surfeit of exotic pine seeds that were released by pine trees as a result of the fire. This unexpected nutritional windfall, in addition to the inclusion of vineyards within their ranging patterns, may explain why there were no physiological indicators of nutritional stress despite the loss of most above ground biomass. Despite suffering the loss of 12 troop members in the fire and injury to a further 12 individuals, adult females in the Tokai troop were able to adjust to a severe and extensive change to their home range. Although primate ecological flexibility has been widely documented, this is the first study to explore the behavioural and physiological responses of baboons to extensive habitat changes resulting from a wildfire, and the potential implications for the management of wildlife on the urban edge.

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