OpenUCT :: Browsing by Author "Spottiswoode, Claire"

Browsing by Author "Spottiswoode, Claire"

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Open Access
Can sociality buffer the impacts of climate change on a cooperatively-breeding bird, the southern pied babbler Turdoides bicolor?
(University of Cape Town, 2020) Bourne, Amanda R; Cunningham, Susan J; Ridley, Amanda R; Spottiswoode, Claire
Increasingly harsh and unpredictable climate regimes are affecting animal populations everywhere and understanding how species respond to current environmental variability is important for predicting vulnerability to climate change over longer timescales. Species living in characteristically harsh and unpredictable arid and semi-arid ecosystems are useful models for studying impacts of climate variability and change because these ecosystems are experiencing rapid increases in both average and maximum temperatures, as well as increased interannual rainfall variation, as a result of anthropogenic climate change. That animals living in highly variable environments are disproportionately more likely to engage in cooperative breeding implies that this strategy may buffer individuals against the negative effects of adverse climate conditions. An aspect of species' vulnerability to climate change that remains relatively unexplored is whether responses to environmental stressors might therefore be mitigated by sociality, particularly in those species in which group members are highly cooperative. In this thesis, I use behaviour, morphology, and physiology data that I collected over three consecutive austral summer field seasons (2016-2019) and A. Prof. Amanda Ridley's 15-year life history dataset (2003-2019, to which I contributed the last three years of data) for a cooperatively-breeding bird, the southern pied babbler Turdoides bicolor. I investigate the impacts of temperature, rainfall, and group size on interannual survival, behaviour, physiology, growth, and reproduction in southern pied babblers, taking a multidisciplinary approach combining behavioural ecology, life history, and ecophysiology. In order to avoid disturbance to the study population, I validated and implemented a non-invasive method for collecting physiological measurements (daily energy expenditure and water turnover). I also tested for the influence of interactions between weather and group size variables because the presence of significant interactions would provide evidence in support of a moderating effect of sociality. I found that exposure to high temperatures significantly constrained successful breeding and the interannual survival of both breeding adults and juvenile birds, and explored the mechanisms behind these observed relationships: adjustments in parental care behaviour, body mass loss, reduced nestling growth rates, and the physiological costs of care at high temperatures. Higher rainfall and larger groups sizes were generally associated with higher reproductive success and survival, but I found no evidence for an interaction between weather variables and group size: individuals across all group sizes experienced similar effects of conditions. I therefore conclude that 1) pied babblers will increasingly face challenges for population recovery and persistence in the near future as survival and reproduction are increasingly compromised by ever higher temperatures, and 2) a life history strategy that relies on the presence of helpers for successful breeding is unlikely to buffer individual group members against climatic variability and climate change in this cooperatively breeding species.
Open Access
Coevolution between brood-parasitic honeyguides and their hosts
(2020) Mcclean, Luke Alexander; Spottiswoode, Claire; Horrocks, Nicholas P C
Obligate brood parasites lay their eggs in the nests of other species, foisting the costs of parental care onto the host parents. The success of the parasite and host are then at odds, with both parties evolving defences and countermeasures in an evolutionary arms race. This reciprocal influence of acting upon both species' evolution — a process known as coevolution — has forged the natural world around us. Avian brood parasites and their hosts are now model systems for studying such coevolutionary interactions between species, providing striking examples of the adaptations that arise when the life histories of two species become entangled. In this thesis I highlight the adaptations that have arisen in response to coevolutionary selection pressures in a group of understudied avian brood parasites, the honeyguides (Indicatoridae), and their hosts. This study focuses on the greater (Indicator indicator) and lesser (I. minor) honeyguides, and their respective primary hosts, the little bee-eater (Merops pusillus) and the black-collared barbet (Lybius torquatus). The interactions between honeyguides and their cavity-nesting hosts of the Old World tropics are evolutionarily ancient, contrasting with the majority of studies of avian brood parasitism which have predominantly focused on temperate brood-parasitic species targeting open cup-nesting hosts. Therefore, honeyguides and their hosts are an ideal study system in which look for novel adaptations that have not evolved in other systems. Using field observations and experimental manipulations at each stage of the parasitic life cycle — before parasitism, during egg-laying, during incubation, and during chickrearing — I examine how honeyguides and their hosts have evolved in response to the selection pressures they exert on each other. First, in chapter two, I consider whether the nest structure of the little bee-eater – host to the greater honeyguide – can act as a defence against brood parasitism. Experimental manipulation of the size of bee-eater nest tunnels demonstrates that bee-eaters with narrower nest tunnels are less likely to be parasitized by greater honeyguides than those bee-eaters whose nests have wider nest tunnel entrances. This study provides the first experimental evidence of a host nest functioning as a frontline defence against brood parasitism. In chapter three, I take a comparative approach and use a phylogenetic framework to investigate, across multiple avian brood parasite species, the evolutionary drivers of rapid egglaying. This trait is shared by most brood-parasitic birds, but not by non-parasitic birds. I find strong evidence that the egg-laying speed of avian brood parasites is ecologically and physiologically constrained, but find no evidence that variation in the costs incurred duringparasitism events have driven variation in the rapidity of egg-laying among brood-parasitic species. In chapter four, I examine whether there are costs associated with the virulent egg puncturing behaviour of greater honeyguides, and whether honeyguides can adjust their level of virulence in accordance with these costs. I find strong support for the idea that virulence is costly to honeyguides, as bee-eater hosts are more likely to reject clutches that contained eggs punctured by honeyguides. Such punctured clutches are also more likely to be predated. Honeyguides appear to adjust how much they puncture host eggs in accordance with the severity of these costs, providing the first evidence of an avian brood parasite moderating its virulence in response to the associated costs. In chapter five, I examine egg rejection behaviour in the black-collared barbet, a common host of the lesser honeyguide. I consider whether the (smaller) size of a parasitic egg could be used as a cue for egg rejection inside the dark environment of a cavity nest. Through observations of natural parasitism events, and experimental parasitism of host nests using different sized eggs, I demonstrate that barbets are more likely to reject a clutch of eggs when they detect a small egg within the nest. This seems to be achieved through a process of true recognition, a mechanism that involves a specific innate or learnt template of what size eggs a host should reject. Barbets do not appear to rely on discordancy – comparing all eggs within their clutch in order to reject the odd one out – in order to make rejection decisions. Finally, in chapter six I explore whether honeyguides elicit additional provisioning from their foster parents by using vocal mimicry, and investigate why such extra food would be required. I demonstrate that both greater and lesser honeyguides mimic the sound of a brood of chicks of their respective hosts in order to receive higher levels of provisioning from their foster parents. I establish that greater and lesser honeyguides do this for contrasting reasons. Greater honeyguides require higher levels of provisioning to support their fast growth rate to a size much larger than their host siblings, whereas lesser honeyguides require more food in order to offset a sub-optimal diet provided to them by their foster parents.
Open Access
The decline of the globally threatened Rudd's Lark in one of its last remaining core sites, the Wakkerstroom grasslands
(2017) Gush, Wesley Gurney; Spottiswoode, Claire; Maphisa, David H; Donald, Paul
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
Open Access
How does surface mining impact surrounding miombo woodland bird communities?
(2022) Hickman, Rowan; Jamie, Gabriel; Spottiswoode, Claire
Africa is estimated to contain almost one quarter of global biodiversity, but also a third of global non-fuel mineral resources. Together with relatively low past exploitation, this has led to a surge in mining investment and development over the past few decades. Mining negatively impacts biodiversity in numerous ways. One hotspot of mining activity in Africa is the Central African Copperbelt, which contains vast copper reserves and half of global minable cobalt. The Central African Copperbelt is located roughly in the centre of the miombo ecoregion, a biodiverse area that is listed as a global conservation priority, which provides ecosystem services that support over 100 million livelihoods. Despite its ecological and social importance, research on the impacts of mining and possible mitigation measures in the ecoregion is limited. This study was conducted in miombo woodlands inside and outside an ecological protection zone surrounding an open pit copper mine in north-western Zambia. It tested effect of distance from the mine, habitat structure and woodland protection on total avian species richness and the species richness of frugivores, granivores, insectivores, woodland and open habitat specialists, breeding and non-breeding species and Zambezian endemics. The results showed that distance from the mine and habitat structure did not significantly explain variation in total species richness or in the species richness of any of the ecological guilds tested. The most likely explanation for this is that mine effects on avian species richness are not detectable at the scale used in this study, implying that by the closest sampling sites (500m from the mines edge) the woodland had mitigated the mine's effects. This suggests that using woodlands as a barrier to mine pollution may be an effective form of mitigation. The results also showed that species richness of frugivores, insectivores, woodland habitat specialists, Zambezian endemic species and breeding species was not significantly explained by protection. However, total species richness and the species richness of granivores, open habitat specialists and non-breeding species all increased significantly outside of the ecological protection zone, which corresponded to woodland surrounded by cropland. These findings highlight the importance of unprotected woodland patches in the conservation of miombo bird species, since these may persist (likely in lower numbers) even in such fragmented patches within transformed habitats. Cropland expansion threatens woodland patches throughout the miombo ecoregion, and while protected areas are undeniably important in biodiversity conservation, matrix habitats may also potentially contribute to the maintenance of miombo species.
Open Access
Individual contributions to group behaviour in the cooperatively breeding southern ground-hornbill Bucorvus leadbeateri
(2023) Middleton, Kyle-Mark; Covas, Rita; Rybak, F; Spottiswoode, Claire
Cooperative breeding, in which individuals other than breeders contribute to raising offspring, has been the focus of much scientific research over the past decades. Why do some individuals help to raise offspring that are not their own? In birds, cooperative breeding is found mainly in harsh regions with greater environmental variability, such that individuals might do better to help relatives than attempt to breed themselves. However, in some bird families cooperative breeding is instead associated with stable and benign environments, suggesting that species may form cooperative groups for different reasons. Most studies have focused on the benefits that additional group members bring to offspring, by increasing provisioning rates, nestling survival, and overall reproductive output. These benefits have been suggested to mitigate the effects of harsh climatic conditions and to be particularly important in the face of anthropogenic climate change, during which increases in temperature extremes and interannual rainfall variability are expected to push species' tolerance to the limit. However, other advantages of group living have been less often considered; for example, collective territory defence is common in cooperative breeders and ensures exclusive access to crucial resources such as food, nesting sites, and mates. A better understanding of the diverse factors favouring cooperative behaviour can offer insights as to why, and in what environmental conditions, social behaviour has evolved, and whether and how it might help animal populations to cope with environmental change. Therefore, the aims of this thesis were to investigate how individuals within cooperative groups contribute to reproduction and territory defence in an atypical cooperative breeder, the southern ground-hornbill Bucorvus leadbeateri. The large body size and exceptionally long lifespan of ground-hornbills leads to a “slow” life-history strategy, providing a striking contrast to most wellstudied avian cooperative breeders, which tend to be small, relatively short-lived passerines. Furthermore, while the hornbill family is usually associated with mesic, stable environments, groundhornbills inhabit semi-arid, fluctuating environments. Studying them thus may shed light on why cooperative breeding might be favoured in both harsh, fluctuating environments, as well as benign, stable environments. I use a combination of my own data collected over five years (2017‒2022) and long-term data collected from the APNR Southern Ground-Hornbill Project (2000‒2022) to test the effects of environmental and social factors (climatic conditions, group size and composition, and age structure of group members) on reproductive and territorial cooperative behaviour. The first two data chapters focus on how group members influence provisioning efforts and reproductive outcomes, and whether group members of different ages can mitigate the effects of harsh climatic conditions. My results showed that high temperatures and low rainfall had generally negative effects on reproduction, and that cooperative breeding provided some reproductive benefits, but did not act as a buffer to provisioning rates or reproductive outputs. Specifically, we showed that adult males had the highest provisioning rates and provisioned larger items, but the additive care they provided did not buffer the effects of high temperatures. Additionally, we showed that hot and dry conditions were associated with decreased breeding probability, later laying dates, and decreased nestling body mass, and that group composition did not significantly mitigate these negative effects. Instead, our results suggested that group or territory quality may be a more important factor in determining reproductive success. The second two data chapters focus on territory defence. Specifically, I asked how different group members contributed to the species' characteristic deep booming chorus vocalisations used to advertise territories, and how responses to territorial intrusions were mediated by caller identity and group size. I showed that calls were significantly different between the sexes, and that females produced sequences of calls that formed unique melodies that could be automatically assigned to the correct individual with a 94% success rate. Melodies are an effective way of signalling individual identity in long distance communication, as this acoustic information travels well when composed of low-pitched sounds. Therefore, since each group generally contains only one adult female, groups can be identified by the female's signature. Next, I showed that there were no clear effects of intruder group identity on the responses of territory holders, but found that group size was positively associated with aggressive responses, indicating that group living may provide resource defence benefits. Overall, the findings in this thesis indicated that group living provided benefits for territory defence and to a lesser extent, reproduction, and that individual contributions of different group members varied between different cooperative behaviours. Despite ground-hornbills inhabiting semiarid regions with harsh climatic conditions, the presence of additional group members of different ages during reproduction were insufficient to mitigate the negative effects of high temperature and low rainfall. However, the likely benefits provided by additional helpers to territory defence suggest that the ecology, longevity, and slow-development of ground-hornbills may render the presence of additional helpers less critical for reproduction, but more important for resource defence. Further research into other group behaviours such as predator vigilance, foraging and hunting, and energy conservation would provide additional insights into other benefits that cooperative breeding might provide. This study implies that a species' life-history strategy may be an important mechanism determining the benefits individuals receive from breeding cooperatively, and so help to explain the ecological correlates and diversity of forms taken by cooperative breeding, including the remarkable biology of the southern ground-hornbill.
Open Access
Mutualism between honeyguides, beekeepers and honey-hunters in the southern highlands of Tanzania
(2023) Kilawi, Amana; Spottiswoode, Claire
The greater honeyguide (hereafter “honeyguide”) is a wax-eating bird species that engages in a remarkable mutualism with humans. Honeyguides use a specialised chattering call to guide honeyhunters to bees' nests, which honey-hunters harvest with the help of smoke and tools. Honey-hunters increase their harvesting yield by finding bees' nests with the help of honeyguides, and honeyguides feed on leftover beeswax. The relationship between honeyguides and honey-hunters in search of wild bees' nests has been well studied, but we know little about the relationship between honeyguides and beekeepers who harvest honey from man-made beehives. I studied the relationship between people and honeyguides in southern Tanzania, in and/or around Ruaha National Park, Rungwa Game Reserve, and Katavi National Park. I visited 20 villages and interviewed 150 people who either practice beekeeping or honey-hunting or do both. I also visited beekeeping camps to observe how people harvest and process honey, and I set camera traps to investigate the fate of beeswax left behind. Specifically, I asked: (i) what is the relationship between honeyguides and beekeepers? (ii) Does honey-hunting with honeyguides persist in southern Tanzania despite beekeeping and if so, how does it function? (iii) What are the ecosystem effects of honey harvesting in southern Tanzania? (iv) What is the future of human-honeyguide interactions in southern Tanzania? Overall, my results suggest that (i) surprisingly, the relationship between honeyguides and beekeepers is often a mutualism, because beekeepers use honeyguides to find beehives that are ready to harvest, and reward honeyguides with an empty wax comb. (ii) Despite being illegal, honey-hunting with honeyguides persists in southern Tanzania; all 66 honey-hunters mentioned that they use honeyguides to find bees ‘nests, and the majority use a specialised calls (particularly “prrrr-prrrr mama”) to communicate with honeyguides. (iii) Honey-hunters typically cut down trees to harvest wild beehives, but beekeepers also destroy trees by cutting down or debarking them to make different types of traditional beehives, typically cylinders made of either bark or solid wood. Many beekeepers possess hundreds of hives, suggesting that beekeeping is not less destructive to trees than honey-hunting, and may be more so. (iv) Interview responses suggested that people are losing interest in following honeyguides due to beekeeping replacing honey-hunting, and due to people, who still want to honey-hunt being constrained from doing so by protected areas, and possibly by climate change and habitat loss causing bee declines. Conversely, interview responses also highlighted beekeepers' use of honeyguides to find their own beehives as a reason why human-honeyguide mutualism continues to thrive in southern Tanzania.
Open Access
The potential impact of climate change on the genetic diversity of the endangered western leopard toad, Sclerophrys pantherina
(2017) Casola, Sarah; Tolley, Krystal A; Spottiswoode, Claire; Visser, Vernon
Climate change is now considered to be one of the greatest threats to the persistence of biodiversity. Much work has focused on the potential for climatic shifts to alter species' ranges, phenology, physiology, and behaviour, addressing higher level units of biodiversity from populations to biomes. However, the potential effects of climate change on the most fundamental unit of biodiversity, intraspecific genetic diversity, has only recently received research attention. Studies to date suggest that the accelerated climatic changes we currently face could cause a loss of intraspecific diversity, hampering the ability of populations to respond to further environmental change. Amphibians are considered to be one of the most vulnerable taxa to climate change. The amphibians of the Western Cape of South Africa provide a powerful opportunity to study the impact of climate change on genetic diversity, as many are endemic, threatened, and generally considered to be poor dispersers, limiting their ability to respond to climatic changes through range shifts. This project had two aims: first, to explore the potential impact of climatic shifts on the genetic landscape of the endemic and Endangered western leopard toad, Sclerophrys pantherina, a species with a disjunct distribution on either side of the Cape Flats. Second, I aimed to test the hypothesis that climatic fluctuations drive genetic divergence, a mechanism which may explain the potential overlap of high diversity areas with areas of high climatic instability. Population genetic analyses supported the findings of previous genetic work on S. pantherina, that populations in the Cape Metropole and the Overstrand Municipality (to the west and east of the Cape Flats, respectively) are genetically distinct, and thus should be treated as separate conservation units. Higher haplotype diversity was identified in the populations in the Cape Metropole when compared with the Overstrand, highlighting the importance of urban habitat patches in harbouring diversity in the species. Distinct pockets of low haplotype diversity were identified at Observatory and Hout Bay, suggesting a lack of connectivity between these and adjacent breeding sites, likely due to urban-associated habitat fragmentation. Species distribution modelling revealed that the species could lose a substantial amount of climatically suitable space in its current area of occurrence by 2070. Furthermore, the degree of loss was not uniform across the species' distribution. The populations of the Cape Metropole were predicted to experience greater losses in climatically suitable space than populations in the Overstrand. Additionally, the change in climatic suitability between the mid-Holocene (6,000 years ago) and present as well as the change in suitability between future (2050 and 2070) and present were significant predictors of genetic diversity, where areas of the greatest change in suitability between time periods were associated with the highest genetic diversity. Future efforts to conserve the species should focus on establishing connectivity between breeding sites to allow for the rescue of genetically depauperate sites. Efforts to mitigate the drastic negative effects of climate change predicted by the species distribution models should prioritise the breeding sites in the Cape Metropole, which are both higher in diversity and at greater risk from climate change. Mitigation efforts will likely require the application of engineered solutions to promote the maintenance of suitable wetland habitat for the species.
Open Access
The effect of supplementary nectar feeders on bird-plant mutualisms in the Cape Fynbos, South Africa
(2021) Du Plessis, Monique; Coetzee, Anina; Seymour, Colleen; Spottiswoode, Claire
Across the world, people feed birds to interact with nature. A variety of feeder types have been developed over the years to target a broad bird community. Attracting nectarivorous birds to gardens using supplementary nectar feeders is a popular human activity across the globe, but few studies have explored its effects on birds and the plants they pollinate. Nectar feeders may have positive effects, facilitating the urban adaptation of nectarivorous birds, and supplementing their diets when floral resources are scarce. However, supplementary feeders may also lure birds away from indigenous vegetation, affecting the rate of visits to bird-pollinated plants, with consequences for seed set. This study is the first to investigate the effect of nectar feeders on an African plantpollinator mutualism. Given that many plant species in the fynbos biome are bird pollinated, this study was conducted in residential gardens and natural vegetation along the urban edge of the Cape Peninsula, South Africa. I carried out a feeding experiment with a matched paired design to answer two main questions: (1) Do nectar feeders affect bird abundance and distribution ranges? If so, (2) do these affect their visitation rates to bird-pollinated plants? I conducted bird surveys to compare relative bird abundance and local distribution patterns for three feeding guilds (i.e., nectar-specialists, nectar-opportunists and non-nectarivores) between feeder and control treatments (Chapter 2). I then tested whether the presence of nectar feeders in gardens affected sunbird visitation rates to two bird-pollinated Erica species (Erica plukenetii subsp. plukenetii and Erica abietina subsp. atrorosea) in the neighbouring vegetation compared to control sites (Chapter 3). In chapter 2, I found that nectar feeders attracted higher densities of avian nectarivores (but not non-nectarivores) to gardens relative to natural vegetation, and decreased their densities in the neighbouring fynbos, even when floral abundance in the neighbouring vegetation was high. In chapter 3, I found that the consequent changes to sunbird distribution patterns (the main pollinators of ericas) seemed to have no influence on visitation rates to E. abietina, but decreased visitation to E. plukenetii flowers within 300 m of gardens with feeders. Thus, nectar feeders may have positive effects for birds themselves by reducing their urban sensitivity but may also have negative effects on the surrounding fynbos ecosystem. Given that nectar feeders appear to compete with the flowers of E. plukenetii, and perhaps those of other birdpollinated species, supplementary feeding may inadvertently threaten bird-plant pollination networks. This issue is particularly concerning in biomes such as the Cape Floristic Region where many bird-pollinated plants occur near urban edges.
Open Access
Understanding the mutualistic interaction between greater honeyguides and four co-existing human cultures in northern Tanzania
(2021) Laltaika, Eliupendo Alaitetei; Spottiswoode, Claire; van der Wal, Jessica
Greater honeyguides (Indicator indicator) eat wax, and to obtain it, they guide people to bees' nests by flying from one tree to another while giving a distinctive chattering call, in the direction of a wild bees' nest. This relationship is mutually beneficial: the hunters harvest valuable honey, and the honeyguides feed on the beeswax leftover from the harvest. In northern Tanzania, multiple human cultural groups live in close proximity in the same geographical area, and most of them practice honey-hunting with the help of honeyguides. Yet, they may differ in cultural traits that determine their relationship with honeyguides. To map this, I visited 12 villages to interview 129 people from the Hadzabe, Ndorobo, Maasai, Sonjo and Datoga cultural groups about their honey-hunting activities and interactions with honeyguides. Specifically, this thesis investigates (i) how important honey and honeyguides are to each human cultural group; (ii) the sounds used by each group to communicate with honeyguides, to test whether honeyguides may have to learn multiple human ‘languages' in the same geographical area; (iii) the traditions of each cultural group concerning whether and how to reward the honeyguide after it has shown them a bees' nest; (iv) the methods used by different cultures to subdue the bees, and whether some of these are more sustainable than the use of fire; (v) each cultural group's ownership traditions concerning wild bees' nests, which might incentivise sustainable honey-hunting practices; and finally, (iv) the likely impact of cultural change for the future of the honeyguide-human mutualism. Overall, my results suggest that (i) the human-honeyguide mutualism still thrives in this region, particularly in the Hadzabe and Ndorobo cultural groups who do not practice bee-keeping; (ii) people from each culture are largely consistent in the calls they use to communicate with honeyguides, but that these calls differ between cultures (but are most similar between the Maasai and Ndorobo people who are culturally close despite many differences in lifestyle); (iii) many cultures deliberately ‘keep the honeyguide hungry' so it shows them more bees' nests, by either concealing the wax (particularly Hadzabe people) or by pretending not to see the bees' nest the bird shows them (particularly Ndorobo people); (iv) people commonly use methods besides fire to subdue bees, specifically because these methods are less harmful to bees, and particularly a fungus called ‘Engishimui' (Scleroderma verrucosum); (v) only the Ndorobo currently have ownership traditions associated with wild bees' nests; and (vi) cultural changes such as bee-keeping were sometimes reported to underlie declines in humanhoney-guide mutualism, but that environmental deterioration of bee habitat because of climate change and pastoralist activities seem to be the biggest threats to the still very active Hadzabe and Ndorobo honey-hunting cultures.

Browsing by Author "Spottiswoode, Claire"

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