Abstract
Vultures are presently the most threatened raptor guild in the world. Threats to vultures are numerous and mainly anthropogenic. Understanding human communities' relationship with threatened species can guide and strengthen conservation initiatives. We assessed the awareness, benefits, beliefs, threats, and conservation perspectives of people surrounding protected areas accommodating the few remaining vulture strongholds in KwaZulu-Natal, South Africa. We conducted a total of 450 semi-structured interviews and seven focus group discussions. Respondents demonstrated a strong awareness of vultures and reportedly derived benefits from having these avian scavengers in their localities. The most cited benefit (65%) was carrion removal. A predominant belief amongst local people was that vultures are potent in traditional medicine (66%); this was regarded by the majority of respondents (79%) as the main driver for the illegal killing of vultures. Most participants (84%) viewed vulture populations to have declined. Overall, local people demonstrated complex but predominantly positive perceptions towards vultures. Mounting evidence of the use of vultures in traditional medicine compels urgent action. We recommend co-learning-based engagements between resource users and conservation scientists.
Zusammenfassung
Die Wahrnehmung von Geiern in einem sozio-ökologischen Kontext: Eine Fallstudie über drei Schutzgebiete in KwaZulu-Natal, Südafrika. Geier sind derzeit die am stärksten bedrohte Greifvogelgruppe der Welt. Die Bedrohungen für Geier sind zahlreich und hauptsächlich anthropogen bedingt. Wenn man die Beziehung von Menschen zu bedrohten Arten versteht, kann man Schutzinitiativen anleiten und stärken. Wir untersuchten das Bewusstsein, den Nutzen, die Überzeugungen, die Gefahren und die Vorstellung bezüglich Schutzmaßnahmen von Menschen in der Umgebung von Schutzgebieten, welche die wenigen verbliebenen Geierhochburgen in KwaZulu-Natal, Südafrika, beherbergen. Wir führten insgesamt 450 halbstrukturierte Interviews und sieben Fokusgruppendiskussionen durch. Die Befragten zeigten ein großes Bewusstsein für Geier und gaben an, dass sie von der Anwesenheit dieser Aasfresser in ihrer Umgebung profitierten. Der am häufigsten genannte Nutzen war die Beseitigung von Aas (65%). Ein vorherrschender Glaube unter den Einheimischen war, dass Geier in der traditionellen Medizin wirksam sind (66%). Dies wurde von der Mehrheit der Befragten als Hauptgrund für das illegale Töten von Geiern angegeben (79%). Die meisten Teilnehmer (84%) waren der Ansicht, dass Geierpopulationen zurückgegangen sind. Insgesamt zeigten die Einheimischen eine komplexe, aber überwiegend positive Wahrnehmung von Geiern. Die zunehmenden Beweise für die Verwendung von Geiern in der traditionellen Medizin zwingen zu dringendem Handeln. Wir empfehlen daher ein kooperatives, auf Erfahrungsaustausch basierendes Zusammenwirken von Ressourcennutzern und Naturschutzwissenschaftlern.
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Introduction
Populations of Old-world vultures have declined dramatically in recent decades because of multiple environmental and anthropogenic threats (Prakash et al. 2003; Ogada et al. 2012; Botha et al. 2017; McClure et al. 2018; Safford et al. 2019). Threats to vultures worldwide include land-use change, food shortages, direct hunting, poisoning, energy infrastructure, and possibly climate change (Virani et al. 2011; Odino et al. 2014; Pomeroy et al. 2015; Botha et al. 2017; Safford et al. 2019). In sub-Saharan Africa, both intentional and unintentional poisoning incidents have been chiefly responsible for most vulture mortalities in the last three decades (Kruger et al. 2015; Botha et al. 2017; Monadjem et al. 2018). In parts of Africa, vultures have been found poisoned, with body parts removed, particularly their heads and feet, and evidence links this to their use in belief-based practices (McKean et al. 2013; Mashele et al. 2021a,b). The ethnomedicinal consumption of vultures is reportedly well-established in South Africa (McKean et al. 2013; Williams et al. 2014; Pfeiffer et al. 2015; Botha et al. 2017). A recent study has indicated that African traditional healers use up to 800 vultures annually in the Kruger to Canyons Biosphere Reserve (Mashele et al. 2021b), which covers an area of about 20 000 km2 (Coetzer et al. 2010).
Protected areas play a significant role as refugia for vultures (Morales-Reyes et al. 2017), but these avian scavengers are wide-ranging, and their activities cover vast areas, including those unprotected, where their vulnerability to mortality is heightened (Kruger et al. 2015; Oliva-Vidal et al. 2022). For example, communal and agricultural lands attract vultures by providing food in the form of livestock and ungulate carcasses (Pfeiffer et al. 2015; Delgado-González et al. 2022). Addressing anthropogenic threats and mortality risks to vultures solely from a protected area standpoint may be ineffective, as vultures cannot be physically confined within the boundaries of protected areas (Kane et al. 2022). Mashele et al. (2021b) reported that vultures used by traditional health practitioners in the Kruger to Canyons Biosphere Reserve were sourced from protected areas and communal rangelands. This, therefore, highlights the importance of considering relationships between local communities and vultures if threats to these species are to be reduced. Data on psycho-social dynamics that directly and indirectly affect vulture conservation can be used to strengthen the effectiveness of conservation initiatives and tools.
Research concerning human–vulture relations provides a rich and unique perspective that is complementary to ecological vulture conservation strategies (Morales-Reyes et al. 2018; Lambertucci et al. 2021; Garcia-Jimenez et al. 2022). However, such research is generally lacking in the context of South Africa (but see Pfeiffer et al. 2015; Mashele et al. 2021a), particularly in KwaZulu-Natal although this province hosts a relatively high diversity of vulture species occurring in the country (Rushworth et al. 2007, 2018; McKean et al. 2013; Kruger et al. 2015). Social sciences provide tools for assessing human dimensions of environmental phenomena (Bennett et al. 2017). Through multidisciplinary approaches, scholars in the field of environmental management have been able to ascertain how local people perceive and adapt to environmental changes (Below et al. 2015). But more importantly, studies of human perceptions, attitudes, beliefs and knowledge have a way of revealing existing and potential threats to species as well as opportunities for improving the conservation of threatened species (Bennett 2016; Nash et al. 2016; Cailly-Arnulphi et al. 2017; Thondhlana and Cundill 2017). Our study investigated the awareness, benefits, beliefs, threats and conservation perspectives of people residing adjacent to three protected areas, housing the remaining vulture strongholds in KwaZulu-Natal, South Africa.
Methods
Study sites
The present study involved communities bordering three protected areas, in KwaZulu-Natal, namely Giant’s Castle Game Reserve, Hluhluwe-iMfolozi Park (HiP) and Mkhuze Game Reserve (Fig. 1).
Giant’s Castle, situated in Maloti Drakensberg Park (MDP), is a World Heritage Site situated on the western boundary of KwaZulu-Natal, forming the border between South Africa and Lesotho (Fig. 1). Giant’s Castle is home to the Bearded (Gypaetus barbatus) and Cape (Gyps coprotheres) Vultures. Both are cliff-nesting species and have sustained dramatic population declines over the last few years. The species have lost large proportions of their home ranges as anthropogenic land uses expanded over time (Brown 1991; Kruger et al. 2015). Bearded and Cape Vultures are globally listed as Vulnerable and Near-Threatened, respectively (Birdlife International 2021a, b). Notably, there is a sharp contrast between the global and regional status of the Bearded Vulture, as this species is listed as Critically Endangered in southern Africa (Kruger et al. 2015).
Mkhuze and HiP are located in uMkhanyakude District Municipality, north of KwaZulu-Natal. This area supports the majority of tree-nesting vulture species remaining in the province (Rushworth et al. 2018), Lappet-faced Vulture (Torgos tracheliotos), globally listed as Endangered as well as the White-backed (Gyps africanus) and White-headed (Aegypius occipitalis) Vultures, both listed as Critically Endangered (BirdLife International 2021c, d, e). The three protected areas are surrounded by isiZulu-speaking communities of Nguni descent, whose livelihoods are predominantly centred around agro-pastoralism. Conservation, tourism, agriculture and trade are other economic activities and sources of employment common in the areas studied (Nsukwini and Bob 2016).
Data collection and analyses
The communities included in this study were located within 15 km of the reference protected areas (Fig. 1). Data were collected between May and August 2019 through household interviews coupled with focus group discussions (FGD). Approval of the ethical appropriacy of the research instrument was granted by the University of KwaZulu-Natal, Ethics committee (Reference: HSS/1089/108D). Permission to conduct research was sourced from the respective traditional authorities in each study area. The research team spent a maximum of 10 days in each study area, during which further analyses of the sites, participation in local events and pilot studies were conducted. The pilot study outcomes helped rephrase some questions and remove those that were considered sensitive such as the level of education. We observed that some participants would suggest that they could not participate in the study because they either never went to school or had low educational attainment. To proceed, we explained that the purpose of the study was to solicit experience-based knowledge.
We followed a simple random sampling technique (Cohen et al. 2017), where every second closest household was selected. This is because rural settlements do not always follow a linear structure. The interviews were semi-structured, consisting of closed and open-ended questions (Dawson 2007; Supplementary information Table S1). The interviews were conducted in isiZulu, mostly at the homesteads of the participants and in the company of trained local research assistants. Interviews lasted between 15 and 45 min. Verbal consent was obtained from each study participant before the interviews were administered. Only participants 18 years and older were invited to participate, and both gender groups were incorporated.
A total of 450 household interviews and seven focus group discussions were conducted. Data were supplemented with observations and informal conversations with key informants working in the conservation sector. The focus group discussions consisted of 12 to 14 members and were non-gender specific (Dawson 2007). Participants were recruited with the assistance of traditional authorities and local field assistants. We hosted seven groups in total, with discussions lasting for up to 1.5 h. Apart from socio-economic and demographic attributes, questions were mainly centred around familiarity with vultures, encounters, benefits, beliefs, threats and conservation perspectives. Data were captured and analysed using Excel© and the Statistical Package for the Social Sciences© (SPSS). Analyses included descriptive statistics, regressions (i.e. ordinal and multinomial) and Chi-Squared tests of significance.
Of the 450 interviews, 430 (96%) qualified for analyses. The interviews that were excluded from the analyses (n = 20) were incomplete, and these mainly included interviews where the participant opted out before the interview was finalised; mainly because of other commitments.
Results
Study composition and respondents’ demographic attributes
A summary of the sample composition, study participants' demographic information, and socioeconomic attributes is shown in Table 1. Fifty-six per cent (n = 240) of the study participants were male, whilst 44% (n = 190) were female. The majority (30%, n = 127) of respondents were between the ages of 42 and 50 years, whilst those between the ages of 18 and 25 years constituted the smallest fraction of our sample (5%, n = 22). The unemployment rate within the study group was high (57%, n = 245). Other respondents were pensioners (20%, n = 85), self-employed individuals (7%, n = 28) and scholars (3%, n = 14).
Most households (52%, n = 198) were involved in agro-pastoralism (a combination of livestock and crop farming) (Table 1). They kept goats and cattle and produced beans, maize, a variety of vegetables, and cotton for subsistence. Livestock ownership and crop farming constituted 24% (n = 91) and 20% (n = 77) of the listed activities, respectively. Natural resource collection was less prevalent across all study sites (4%, n = 14). Resources collected were plant material for craft, firewood, wild fruits and bushmeat. All activities were small-scale and predominantly subsistence-based.
Local people’s awareness and familiarity with vultures
The present study was conducted in two geographically distinct regions of Maloti Drakensberg Park and northern KwaZulu-Natal, with different vulture species occurring in them. Most participants (84%, n = 361) reported encountering vultures within 12 months of the study. A standard-resolution image list was provided for respondents to identify the species they had seen. The list contained images of six vulture species, five resident, and one locally extinct (Supplementary Information Table S1). Respondents (89%, n = 320) accurately identified species in relation to their local geographic distribution. Encounters were reflective of species’ population densities. For example, respondents reported more sightings of White-backed (47%, n = 150) and Cape (40%, n = 128) Vultures in comparison with Bearded Vultures (2%, n = 6) (Fig. 2a). Vulture awareness amongst the participants was strong (95%, n = 408), albeit at different levels (Fig. 2b). To gauge awareness levels, we considered responses to encounter (Yes/No), species encountered, site of encounter and activity of the species during encounter (Fig. 3).
Respondents who demonstrated a high level of awareness were many (57%, n = 323). Study site and gender were found to be significant in predicting awareness and familiarity with vultures. Respondents living around Giant’s Castle GR were likely to fall within the high level of awareness category (Wald = 25.3, P = 0.0001) and were 6.2 times more likely to exhibit high awareness than participants living near Mkhuze. With reference to gender, males were 1.7 times more likely to demonstrate high levels of awareness than female participants (Wald = 4.3, P = 0.039) (Supplementary information Table S2).
Benefits derived by local people from having vultures in their localities
Most (82%, n = 354) participants derived benefits from coexisting with vultures. The majority of respondents (65%, n = 199) appreciated vultures for feeding on carcasses in the fields, thus keeping the environment clean (regulatory services). Northern KwaZulu-Natal participants gave accounts of the past few years when they experienced severe drought conditions in the region and cattle mortality was high. Respondents stated that carcass management would have been a major challenge to livestock owners had it not been for vultures coming into communal lands and consuming the dead cattle. They further reported that the environment would have been uninhabitable because of the smell of rotting carcasses if vultures had not fed on them. Vultures were also admired for helping residents find livestock that had gone missing (20%, n = 71). In rural areas, cattle often graze unattended and can die without anyone knowing their whereabouts. Vultures flying in circles over an area is indicative of a carcass presence. Farmers find their missing and dead cattle by following vulture movements. Furthermore, 14% (n = 49) of the participants admired vultures for their importance as constituents of local natural heritage – to be preserved for future generations. Tourism and bushmeat were the least mentioned benefits associated with vultures in the communities visited (1.4% and 1%, respectively).
Gender was significant in predicting benefits perceived by local people. Male participants were 2.1 times more likely to cite a benefit from carcass removal than females (Wald = 7.6, P = 0.006). These respondents were also 3.4 times more likely to benefit from the location of missing livestock than their female counterparts (Wald = 12, P = 0.0001). In addition, natural heritage was a benefit mostly mentioned by males 3.7 times more than females (Wald = 11, P = 0.001) (Supplementary information Table S3).
Locally shared beliefs about vultures
Only 25% (n = 108) of the study participants presented beliefs about vultures (Fig. 4). The most predominant belief was associated with vultures having traditional medicine properties (66%; n = 71). In addition, a sighting of vultures circling over one’s property was believed to indicate an impending great misfortune (20%; n = 22). A small proportion of respondents believed vultures to be bearers of rain and luck (11% and 3%, respectively). Again, beliefs about vultures were best explained by gender. Male participants were 8.2 times more likely to believe in vultures as having a value in traditional medicine rather than indicators of misfortune than females (Wald = 12.8, P = 0.0001) (Supplementary information Table S4).
Threats to vultures
Indirect threats: solutions to problem-causing animals
Results from our pilot study highlighted that wildlife invasions in communal lands frequently occurred. To ascertain whether vultures were exposed to indirect poisoning in the form of problem-causing animal control, we asked the participants about their management of damage-causing wild animals. Wild animals reported to cause problems in communal lands were Leopard (Panthera pardus), Spotted Hyaena (Crocuta crocuta), Black-backed Jackal (Canis mesomelas), Serval (Serval leptailurus), Chacma Baboon (Papio ursinus), Pied Crow (Corvus albus) and eagles. Damages caused were mainly livestock depredation and occasional crop raiding. The reporting of incidents to protected area authorities was the most common response to problem-causing animals (37%, n = 107) (Fig. 5). The second most predominant response was retaliation through hunting with dogs (30%, n = 87). Other respondents cited the use of snares/traps (11%, n = 32). The use of poisoned baits was less common in the surveyed areas (2%, n = 6) (Fig. 5). Some respondents reported moving their activities to areas with less wildlife interference.
Direct threats: What drives the killing of vultures by residents?
Forty-five per cent (n = 193) of the respondents expressed awareness of factors that motivated the hunting of vultures in their local areas. Traditional medicine use was the most reported driver for hunting vultures (93%, n = 181). Vultures were rarely hunted for sport or bushmeat (3% and 2%, respectively). Similarly, the killing of vultures as a result of conflict with humans was almost non-existent (2%, n = 2) (Fig. 6).
Local people’s vulture conservation perspectives
We investigated the status of vulture populations from the local people’s perspective. Many participants had noticed changes in vulture populations over the last 10 years (63%, n = 272). Most (84%, n = 228) believed that vulture populations were in decline (Table 2). The majority of respondents (83%, n = 357) stated that vultures should be protected mainly through collaborative efforts between conservation agencies and local communities. However, a significant proportion of respondents (33%, n = 117) perceived that vultures were better off in the hands of conservation agencies (Table 2).
Support for the protection of vultures was determined by study site, gender and age. Giant’s Castle residents were 2.8 times more likely to support vulture protection than Mkhuze respondents (Wald = 6.9, P = 0.009). Similarly, HiP residents were even more (5.6 times) likely to favour vulture protection than their neighbours in Mkhuze (Wald = 20.7, P = 0.0001). Male respondents were reportedly less likely (0.3 times) to support vulture protection than females (Wald = 13, P = 0.0001) (Supplementary information Table S5). The latter finding is contradictory to perceptions expressed by male participants throughout this study. Furthermore, our analyses showed that the oldest members of our study, respondents over 50 years, were more likely to support vulture protection than all other age groups represented in the study.
Discussion
Local people’s awareness and familiarity with vultures
The present study builds on assessments of public perceptions about vultures conducted in parts of southern Africa (Mdhlano et al. 2018; Craig et al. 2018; Mashele et al. 2021a) and southwest Europe (Cortés-Avizanda et al. 2018; Morales-Reyes et al. 2018; Oliva-Vidal et al. 2022). It is the first of its kind in KwaZulu-Natal, an important ecological zone for vultures.
Many respondents reported encounters with vultures and could identify the species they had seen from the image list provided. The majority of encounters were related to species’ local spatial distribution. For example, Giant’s Castle respondents were more familiar with Cape and Bearded vultures, whereas respondents from Mkhuze and HiP were familiar with White-backed, Lappet-faced and White-headed vultures. Moreover, encounters with vultures were in accordance with species’ relative abundance (Rushworth et al. 2018). More common species, such as White-backed and Cape vultures, were frequently cited as species encountered contrary to species with lower population numbers. Local people demonstrated considerable awareness of vultures. When awareness was tested at different levels, more than half of the respondents obtained the highest score.
Awareness was best predicted by study site and gender. Respondents residing adjacent to Giant’s Castle were more likely to demonstrate increased familiarity with vultures. This can be attributed to greater visualisation in Giant’s Castle as the vultures in this area occupy mountain cliffs surrounding villages and are seen almost on a daily basis flying in and out of their roosts. Furthermore, high awareness levels were predominantly observed in male rather than in female participants. Numerous narratives about vultures were willingly shared by men, often with great passion. Other studies have shared similar observations (Ehlers-Smith et al. 2021; Hariohay et al. 2022). According to Pam et al. (2018), people often learn better about nature through personal encounters. The assignment of duties is often governed by traditional gender roles, especially in rural agro-pastoralist communities (Pokou et al. 2021). Accordingly, men spend most of their time in the wilderness rearing livestock, hunting and gathering various raw materials (Hariohay et al. 2022). Spending time in the wilderness facilitates exposure to wildlife, enhancing familiarity and increasing knowledge about resident wildlife (Clamsen and Roskaft 2013; Pokou et al. 2021). From a conservation perspective, adequate awareness amongst local people is admirable as studies show that where awareness is limited, misinformation prevails, posing a threat to species, especially those with peculiar behaviours such as vultures (Margalida and Donázar 2020; Lambertucci et al. 2021; Oliva-Vidal et al. 2022).
Benefits derived by local people from having vultures in their localities
Generally, birds provide numerous economic, cultural and ecological benefits that broadly support human well-being and livelihoods (Clamsen and Røskaft 2013; Mwadzingeni et al. 2018; Garcia-Jimenez et al. 2021). Benefits derived from coexisting with wildlife can play a key role in shaping local people’s perceptions and attitudes towards biodiversity and its conservation (Partasasmita et al. 2016; Ehlers-Smith et al. 2021). Different population groups, such as farmers and tourists, appreciate vultures for providing niche-based provisioning, regulatory and cultural ecosystem services (Cortés-Avizanda et al. 2018; Garcia-Jimenez et al. 2021). Many of our study participants derived benefits from the occurrence of vultures in their environments. Carrion removal was the most appreciated service provided by vultures as it reportedly helps keep the environment habitable, whilst possibly preventing the spread of diseases from animals to humans (Morales-Reyes et al. 2018). Study participants from northern KwaZulu-Natal (HiP and Mkhuze) gave a narrative about a severe drought that hit the region between 2015 and 2016, decimating large herds of livestock (Vetter et al. 2020; Lottering et al. 2021). More than 40 000 cattle were lost by the end of 2015 in KwaZulu-Natal (Vetter et al. 2020). Respondents indicated that vultures removed most carcasses that the community would have otherwise battled to dispose of timely.
Carrion removal is the most recognised and valued material benefit of human-vulture coexistence worldwide (Moleón et al. 2014; Cortes-Avizanda et al. 2018; Craig et al. 2018; Mdhlano et al. 2018). In a study conducted in two municipalities of the Eastern Cape Province, Pfeiffer et al. (2015) indicated that 82% of the participants noted that Cape vultures consumed livestock that had died from natural causes or predation. It has been established that vultures have a natural competitive advantage over scavenging mammals and can control their populations, especially in communal lands (Whelan et al. 2008). Vultures are also the only scavenger guild that can alternate between protected areas and communal lands without initiating cogent human-wildlife conflict. Moreover, evidence suggests that by optimising on the freely available carrion removal service provided by vultures, regions can reduce their carbon footprint and save on monetary resources (Morales-Reyes et al. 2015).
Vultures were also valuable to local people for assisting in locating missing cattle. Herders often found the location of their lost and often dead cattle by following vulture cues. This relationship has been observed in other parts of southern Africa (Craig et al. 2018; Mdhlano et al. 2018). Carcass location is an essential contribution because many rural communities in southern Africa customarily rely on livestock farming for economic and cultural purposes. During the dry season, when pasture and drinking water are reduced, cattle are compelled to travel long distances searching for food and water, often unattended. By being naturally drawn to carcasses, vultures provide cues for owners to locate their cattle in the event of death. This information can help farmers quantify costs and adopt better management and monitoring practices to reduce cattle mortalities. The aforementioned scenario provides evidence of local people using local ecological knowledge (LEK) and experience to take advantage of ecosystem services (Morales-Reyes et al. 2018; Ehlers Smith et al. 2021).
Locally shared beliefs about vultures
A few participants (25%) presented beliefs about vultures, mainly concerning their alleged traditional medicine usefulness. Vultures are believed to have a keen sense of smell, enabling them to locate carcasses from vast distances. Locally, they are otherwise called izwangomoya (main name: Inqe) because they find food by deciphering the contents of the air whilst flying, often in circular motions. Therefore, by using certain vulture parts, especially the head, ordinary people can gain the ability to see into the future or obtain information that would otherwise be inaccessible to them. However, this belief contradicts scientific evidence, demonstrating that Old-world vultures locate carcasses by sight, relying on collective foraging strategies and following cues provided by other scavengers (Kane et al. 2014; Buechley and Şekercioğlu 2016). Nonetheless, the belief-based use of vultures is seemingly prevalent in southern Africa (Cunningham and Zondi 1991; McKean et al. 2013; Williams et al. 2014; Mdhlano et al. 2018; Mashele et al. 2021b). In the current study, traditional medicine was the most reported driver for the killing of vultures, especially in northern KwaZulu-Natal. Ogada et al. (2016) state that traditional medicine is responsible for approximately 29% of African vulture mortalities. Existing evidence further indicates that the use of vulture parts in traditional medicine is projected to increase. Hence, McKean et al. (2013) suggest the formulation of strategies aimed at supporting cultural traditions whilst ensuring the long-term persistence of natural resources that form part of these beliefs. Such initiatives may require meaningful deliberations between resource users and conservation practitioners.
Culturally, human-raptor relations are complex, ranging from raptors being considered sacred to being perceived as bad omens (Wyndham and Park 2018; Horgan et al. 2021). Despite being known as bringers of luck and rain, owing to their close association with carcasses, vultures were believed by many (20%) participants to indicate an impending misfortune if they were spotted flying in a circular motion above someone’s property. We link this belief to an isiZulu idiom, uzulelwa amanqe, meaning vultures are hovering over you. This phrase is often used when threatening or warning someone whose behaviour is about to land them in danger. Such impressions suggest that historically, vultures were once widespread across KwaZulu-Natal, and interactions with local people were established, gaining their prominence in the isiZulu culture and folklore. These findings reveal nuances of non-material culture and identity-related values of vultures worth exploring (Garcia-Jimenez et al. 2022).
Threats to vultures and conservation perspectives
Socio-ecological landscapes are synonymous with human-wildlife conflicts. Most commonly, cases of human-wildlife conflict involve predators preying on livestock and farmers resorting to using poison to eradicate the perceived culprits. Farmers have long considered poisoning the most effective predator control method (Ogada 2014). Although vultures are seldom targeted in retaliatory wildlife killings, they do, however, fall victim to unintentional poisoning (Ogada 2014), representing one of the major threats to vulture populations globally (Margalida et al. 2011; Ogada et al. 2012; Botha et al. 2017; Safford et al. 2019). In the present study, participants responded to human-wildlife conflict by reporting cases to the neighbouring protected area, and the use of poison was rarely reported. Similarly, Pfeiffer et al. (2015) found that using poison in predator management was not common in communities neighbouring the Msikaba Cape Vulture Colony. The use of toxic substances to kill wildlife is illegal, whilst most apex predators are threatened and therefore protected by the law against the illegal killing (Ogada et al. 2003; Lindsey et al. 2013). It is then likely that respondents underreported their use of poison against problem-causing animals in fear of potential prosecution (Shanee 2012). Therefore, these results should be interpreted with caution.
Only two per cent of our participants reported cases of conflict with vultures, and these were mainly in the form of chicken depredation. Reports of vultures preying on domestic animals such as sheep and cattle have become common in recent years, especially in Europe, but conservation practitioners are challenging these reports as anecdotal and biassed (Margalida et al. 2011; 2014; Duriez et al. 2019; Margalida and Donázar 2020; Oliva-Vidal et al. 2022). It has been shown that 70% of complaints by farmers against vultures are shown to be post-mortem cases and thus rejected (Margalida et al. 2014; Duriez et al. 2019). Both Old and New world vultures are not tailored for predatory behaviour. In the rare cases where vultures inflicted harm on livestock, it was mainly through secondary interference, such as causing minor injuries on frail animals, which may have resulted in a fatality (Duriez et al. 2019). Unfortunately, the essentially rare cases of human-vultures conflict are amplified on social media platforms with risks of mass misinformation that could further culminate in unwarranted enmity towards vultures (Margalida et al. 2014; Margalida and Donázar 2020).
Population dynamics and conservation perspectives
Vulture populations were perceived to have declined in the last 10 years by respondents and in other studies (Safford et al. 2019). This observation agrees with empirical reports largely indicating that vulture populations across southern Africa have declined dramatically over the last three decades (Ogada et al. 2012, 2016; Kruger et al. 2015; Rushworth et al. 2018). The protection of vultures was supported by a great number of respondents. This outcome could be attributed to their natural heritage importance (non-material) as well as the tangible benefits that local people enjoy by having vultures in their localities. We tested support for the protection of vultures against demographic and socioeconomic indices. Age and gender were found to be the best predictors of support for vulture conservation. Participants over 50 years were most likely to advocate for the protection of vultures. Surprisingly, male participants were less likely to favour protecting vultures than female participants. This finding was in contradiction with the perceptions expressed by men throughout the study. Male participants exhibited stronger awareness of vultures. These participants also perceived vultures as useful, more than their female counterparts. Regarding beliefs, men were less likely to associate vultures with misfortunes. We found that most participants, males, in particular, were positive about vultures and wished to see them thrive in their localities.
Conclusions
Our results suggest that vultures are salient in the landscapes they occupy as providers of regulatory and provisioning ecosystem services (i.e. carrion removal and signalling livestock carcass location). Vulture awareness and familiarity amongst local people were adequate and may have played a role in facilitating the recognition of ecosystem services provided by vultures. The study participants exhibited predominantly positive perceptions towards vultures, which is interesting because, in contrast with South Africa, studies conducted in Europe report negative perceptions exhibited by local people (Morales-Reyes et al. 2018; Oliva-Vidal et al. 2022). Our findings can be considered in designing vulture conservation initiatives. Further, we propose incorporating vulture conservation initiatives into the already existing local community-based programmes. One particular example is the horse racing initiative that is gaining momentum in rural KwaZulu-Natal. It mainly involves young people as horse riders, and it is competition based. Vultures can be incorporated, for instance, in the naming of horses and event themes. This can be a channel for awareness raising, especially amongst young people and can challenge the existing and emerging negative perceptions, especially those relating to vultures as being useful in traditional medicine.
Availability of data and material
Data for this study belong to the University of KwaZulu-Natal but are available on request from the authors.
References
Below TB, Schmid JC, Sieber S (2015) Farmers’ knowledge and perception of climatic risks and options for climate change adaptation: a case study from two Tanzanian villages. Reg Environ Change 15:1169–1180. https://doi.org/10.1007/s10113-014-0620-1
Bennett NJ (2016) Using perceptions as evidence to improve conservation and environmental management. Conserv Biol 30:582–592. https://doi.org/10.1111/cobi.12681
Bennett NJ, Roth R, Klain SC, Chan K, Christie P, Clark DA, Cullman G, Curran D, Durbin TJ, Epstein G (2017) Conservation social science: Understanding and integrating human dimensions to improve conservation. Biol Conserv 205:93–108. https://doi.org/10.1016/j.biocon.2016.10.006
BirdLife International (2021a) Gypaetus barbatus. The IUCN Red List of Threatened Species 2021a: e.T22695174A154813652. https://dx.doi.org/https://doi.org/10.2305/IUCN.UK.2021-3.RLTS.T22695174A154813652.en. Accessed on 19 July 2022
BirdLife International (2021b) Gyps coprotheres. The IUCN Red List of Threatened Species 2021b: e.T22695225A197073171. https://dx.doi.org/https://doi.org/10.2305/IUCN.UK.2021-3.RLTS.T22695225A197073171.en. Accessed on 19 July 2022
BirdLife International (2021c) Gyps africanus. The IUCN Red List of Threatened Species 2021c.T22695189A204461164. https://dx.doi.org/https://doi.org/10.2305/IUCN.UK.2021-3.RLTS.T22695189A204461164.en. Accessed on 19 July 2022
BirdLife International (2021d) Aegypius occipitalis. The IUCN Red List of Threatened Species (2021d):e.T22695250A205380033. https://dx.doi.org/https://doi.org/10.2305/IUCN.UK.2021-3.RLTS.T22695250A205380033.en. Accessed on 19 July 2022
BirdLife International (2021e) Torgos tracheliotos. The IUCN Red List of Threatened Species 2021e: e.T22695238A205352949. https://dx.doi.org/https://doi.org/10.2305/IUCN.UK.2021-3.RLTS.T22695238A205352949.en. Accessed on 19 July 2022
Botha A, Andevski J, Bowden C, Gudka M, Safford R, Tavares J, Williams NP (2017) Multi-species action plan to conserve African-Eurasian vultures. CMS Raptors MOU Tech Publ 5:1–164
Brown C (1991) An investigation into the decline of the Bearded Vulture Gypaetus barbatus in southern Africa. Biol Conserv 57:315–337. https://doi.org/10.1016/0006-3207(91)90075-K
Buechley ER, Şekercioğlu ÇH (2016) The avian scavenger crisis: Looming extinctions, trophic cascades, and loss of critical ecosystem functions. Biol Conserv 198:220–228. https://doi.org/10.1016/j.biocon.2016.04.001
Cailly Arnulphi VB, Lambertucci SA, Borghi CE (2017) Education can improve the negative perception of a threatened long-lived scavenging bird, the Andean condor. PLoS ONE 12(9):e0185278. https://doi.org/10.1371/journal.pone.0185278
Clamsen ME, Røskaft E (2013) Knowledge of birds of conservation interest among the people living close to protected areas in Serengeti, Northern Tanzania. Int J Biodivers Sci Ecosys Serv Manage 9:114–122. https://doi.org/10.1080/21513732.2013.788566
Coetzer KL, Erasmus BF, Witkowski ETF, Bachoo AK (2010) Land-cover change in the Kruger to Canyons Biosphere Reserve (1993–2006): a first step towards creating a conservation plan for the subregion. S Afr J Sci 106:1–10. https://hdl.handle.net/10520/EJC97059
Cohen L, Manion L, Morrison K (2017) Research methods in education. Routledge
Cortés-Avizanda A, Martín-López B, Ceballos O, Pereira HM (2018) Stakeholders perceptions of the endangered Egyptian vulture: Insights for conservation. Biol Conserv 218:173–180. https://doi.org/10.1016/j.biocon.2017.09.028
Craig CA, Thomson RL, Santangeli A (2018) Communal farmers of Namibia appreciate vultures and the ecosystem services they provide. Ostrich 89:211–220. https://doi.org/10.2989/00306525.2018.1435566
Cunningham AB, Zondi A (1991) Use of animal parts for the commercial trade in traditional medicines: University of Natal, Institute of Natural Resources, Pietermaritzburg
Dawson C (2007) A practical guide to research methods. Begbroke: Oxford OX5 1RX, United Kingdom
Delgado-González A, Cortés-Avizanda A, Serrano D, Arrondo E, Duriez O, Margalida A, Carrete M, Oliva-Vidal P, Sourp E, Morales-Reyes Z, García-Barón I (2022) Apex scavengers from different European populations converge at threatened savannah landscapes. Sci Rep 12:1–10. https://doi.org/10.1038/s41598-022-06436-9
Duriez O, Descaves S, Gallais R, Neouze R, Fluhr J, Decante F (2019) Vultures attacking livestock: a problem of vulture behavioural change or farmers’ perception? Bird Conserv Int 29:437–453. https://doi.org/10.1017/S0959270918000345
Ehlers Smith YC, Maseko MS, Sosibo M, Dlamini PV, Gumede ST, Ngcobo SP, Tsoananyane L, Zungu MM, Ehlers Smith DA, Downs CT (2021) Indigenous knowledge of South African bird and rangeland ecology is effective for informing conservation science. J Environ Manage 284:112041. https://doi.org/10.1016/j.jenvman.2021.112041
García-Jiménez R, Morales-Reyes Z, Pérez-García JM, Margalida A (2021) Economic valuation of non-material contributions to people provided by avian scavengers: Harmonizing conservation and wildlife-based tourism. Ecol Econ 187:107088. https://doi.org/10.1016/j.ecolecon.2021.107088
García-Jiménez R, Pérez-García JM, Margalida A, Morales-Reyes Z (2022) Avian scavengers’ contributions to people: The cultural dimension of wildlife-based tourism. Sci Total Environ 806:150419. https://doi.org/10.1016/j.scitotenv.2021.150419
Hariohay KM, Nassary DS, Lyamuya RD, Røskaft E (2022) Local people’s knowledge of topi (Damaliscus lunatus) and their illegal hunting for bushmeat consumption in the Serengeti Ecosystem. Afr J Ecol 60:268–276. https://doi.org/10.1111/aje.12978
Horgan FG, Mundaca EA, Crisol-Martínez E (2021) Emerging patterns in cultural ecosystem services as incentives and obstacles for raptor conservation. Birds 2:185–206. https://doi.org/10.3390/birds2020014
Kane A, Jackson AL, Ogada DL, Monadjem A, McNally L (2014) Vultures acquire information on carcass location from scavenging eagles. Proc Royal Soc B: Biol Sci 281:20141072. https://doi.org/10.1098/rspb.2014.1072
Kane A, Monadjem A, Aschenborn H, Bildstein K, Botha A, Bracebridge C, Buechley ER, Buij R, Davies JP, Diekmann M (2022) Understanding continent-wide variation in vulture ranging behavior to assess feasibility of Vulture Safe Zones in Africa: Challenges and possibilities. Biol Conserv 268:109516. https://doi.org/10.1016/j.biocon.2022.109516
Krüger SC, Simmons RE, Amar A (2015) Anthropogenic activities influence the abandonment of Bearded Vulture (Gypaetus barbatus) territories in southern Africa. Condor 117:94–107. https://doi.org/10.1650/CONDOR-14-121.1
Lambertucci SA, Margalida A, Speziale KL, Amar A, Ballejo F, Bildstein KL, Blanco G, Botha AJ, Bowden CG, Cortés-Avizanda A, Duriez O (2021) Presumed killers? Vultures, stakeholders, misperceptions, and fake news. Conserv Sci Pract 3:e415. https://doi.org/10.1111/csp2.415
Lindsey PA, Balme G, Becker M, Begg C, Bento C, Bocchino C, Dickman A, Diggle RW, Eves H, Henschel P (2013) The bushmeat trade in African savannas: Impacts, drivers, and possible solutions. Biol Conserv 160:80–96. https://doi.org/10.1016/j.biocon.2012.12.020
Lottering SJ, Mafongoya P, Lottering R (2021) The impacts of drought and the adaptive strategies of small-scale farmers in uMsinga, KwaZulu-Natal, South Africa. J Asian Afr Stud 56:267–289. https://doi.org/10.1177/0021909620916898
Margalida A, Donázar JA (2020) Fake News and Vultures. Nat Sustain 3:492–493. https://doi.org/10.1038/s41893-020-0534-5
Margalida A, Campión D, Donázar JA (2011) European vultures’ altered behaviour. Nature 480:457
Margalida A, Campión D, Donázar JA (2014) Vultures vs livestock: conservation relationships in an emerging conflict between humans and wildlife. Oryx 48:172–176. https://doi.org/10.1017/S0030605312000889
Mashele N, Thompson LJ, Downs CT (2021a) Traditional health practitioners’ and other community members’ perceptions of vultures in the Kruger to Canyons Biosphere Region. South Africa J Raptor Res 55:340–358. https://doi.org/10.3356/JRR-20-34
Mashele N, Thompson LJ, Downs CT (2021b) Uses of vultures in traditional medicines in the Kruger to Canyons Biosphere Region, South Africa. J Raptor Res 55:328–339. https://doi.org/10.3356/JRR-20-36
McClure CJ, Westrip JR, Johnson JA, Schulwitz SE, Virani MZ, Davies R, Symes A, Wheatley H, Thorstrom R, Amar A (2018) State of the world’s raptors: Distributions, threats, and conservation recommendations. Biol Conserv 227:390–402. https://doi.org/10.1016/j.biocon.2018.08.012
McKean S, Mander M, Diederichs N, Ntuli L, Mavundla K, Williams V, Wakelin J (2013) The impact of traditional use on vultures in South Africa. Vulture News 65:15–36. https://doi.org/10.4314/vulnew.v65i1.2
Mdhlano SF, Gandiwa E, Muboko N, Mashapa C (2018) Local knowledge and perceptions of vulture conservation in communities living adjacent to the northern Gonarezhou National Park, Zimbabwe. Vulture News 74:1–10. https://doi.org/10.4314/vulnew.v74i1.1
Moleón M, Sanchez-Zapata JA, Margalida A, Carrete M, Owen-Smith N, Donázar JA (2014) Humans and scavengers: the evolution of interactions and ecosystem services. BioScience 64:394–403. https://doi.org/10.1093/biosci/biu034
Monadjem A, Kane A, Botha A, Kelly C, Murn C (2018) Spatially explicit poisoning risk affects survival rates of an obligate scavenger. Sci Rep 8:1–11. https://doi.org/10.1038/s41598-018-22632-y
Morales-Reyes Z, Pérez-García JM, Moleón M, Botella F, Carrete M, Lazcano C, Moreno-Opo R, Margalida A, Donázar JA, Sánchez-Zapata JA (2015) Supplanting ecosystem services provided by scavengers raises greenhouse gas emissions. Sci Rep 5:1–6. https://doi.org/10.1038/srep07811
Morales-Reyes Z, Pérez-García JM, Moleon M, Botella F, Carrete M, Donazar JA, Cortés-Avizanda A, Arrondo E, Moreno-Opo R, Jiménez J, Margalida A (2017) Evaluation of the network of protection areas for the feeding of scavengers in Spain: from biodiversity conservation to greenhouse gas emission savings. J Appl Ecol 54:1120–1129. https://doi.org/10.1111/1365-2664.12833
Morales-Reyes Z, Martín-López B, Moleón M, Mateo-Tomás P, Botella F, Margalida A, Donázar JA, Blanco G, Pérez I, Sánchez-Zapata JA (2018) Farmer perceptions of the ecosystem services provided by scavengers: what, who, and to whom. Conserv Lett 11:e12392. https://doi.org/10.1111/conl.12392
Mwadzingeni K (2018) Linking perceptions of diversity and importance to occurrence of avifauna in rural communities and the implications for conservation: a case study of Mupari communal area, Shurugwi, Zimbabwe. MSc Thesis. Midlands State University, Gweru
Nash HC, Wong MH, Turvey ST (2016) Using local ecological knowledge to determine status and threats of the Critically Endangered Chinese pangolin (Manis pentadactyla) in Hainan, China. Biol Conserv 196:189–195. https://doi.org/10.1016/j.biocon.2016.02.025
Nsukwini S, Bob U (2016) The socio-economic impacts of ecotourism in rural areas: A case study of Nompondo and the Hluhluwe-iMfolozi Park (HiP). Afr J Hosp Tourism Leisure 5:1–15
Odino M, Imboma T, Ogada D (2014) Assessment of the occurrence and threats to Hooded Vultures Necrosyrtes monachus in western Kenyan towns. Vulture News 67:3–20. https://doi.org/10.4314/vulnew.v67i2.1
Ogada DL (2014) The power of poison: pesticide poisoning of Africa’s wildlife. Ann N Y Acad Sci 1322:1–20. https://doi.org/10.1111/nyas.12405
Ogada MO, Woodroffe R, Oguge NO, Frank LG (2003) Limiting depredation by African carnivores: the role of livestock husbandry. Conserv Biol 17:1521–1530. https://doi.org/10.1111/j.1523-1739.2003.00061.x
Ogada D, Torchin M, Kinnaird M, Ezenwa V (2012) Effects of vulture declines on facultative scavengers and potential implications for mammalian disease transmission. Conserv Biol 26:453–460. https://doi.org/10.1111/j.1523-1739.2012.01827.x
Ogada D, Shaw P, Beyers RL, Buij R, Murn C, Thiollay JM, Beale CM, Holdo RM, Pomeroy D, Baker N (2016) Another continental vulture crisis: Africa’s vultures collapsing toward extinction. Conserv Lett 9:89–97. https://doi.org/10.1111/conl.12182
Oliva-Vidal P, Hernández-Matías A, García D, Colomer MÀ, Real J, Margalida A (2022) Griffon vultures, livestock and farmers: Unraveling a complex socio-economic ecological conflict from a conservation perspective. Biol Conserv 272:109664. https://doi.org/10.1016/j.biocon.2022.109664
Pam G, Zeitlyn D, Gosler A (2018) Ethno-Ornithology of the Mushere of Nigeria. Ethnobiol Lett 9: 48–64. https://doi.org/10.14237/ebl.9.2.2018.931
Partasasmita R, Iskandar J, Malone N (2016) Karangwangi people's (South Cianjur, West Java, Indonesia) local knowledge of species, forest utilization and wildlife conservation. J Biol Divers 17: 154–161. https://doi.org/10.13057/biodiv/d170123
Pfeiffer MB, Venter JA, Downs CT (2015) Identifying anthropogenic threats to Cape Vultures Gyps coprotheres using community perceptions in communal farmland, Eastern Cape Province, South Africa. Bird Conserv Int 1:1–13. https://doi.org/10.1017/S0959270914000148
Pokou KP, Piba NAS, Bosso AV (2021) Local population’s knowledge and perceptions on the biodiversity and conservation status of land snails in the region of Lamto Reserve at The Centre of Ivory Coast. Euro Sci J 17: 241–256. https://doi.org/10.19044/esj.2021.v17n25p241
Pomeroy D, Shaw P, Opige M, Kaph G, Ogada DL, Virani MZ (2015) Vulture populations in Uganda: using road survey data to measure both densities and encounter rates within protected and unprotected areas. Bird Conserv Int 25:399–414. https://doi.org/10.1017/S095927091400029X
Prakash V, Pain DJ, Cunningham AA, Donald P, Prakash N, Verma A, Gargi R, Sivakumar S, Rahmani AR (2003) Catastrophic collapse of Indian white-backed Gyps bengalensis and long-billed Gyps indicus vulture populations. Biol Conserv 109:381–390. https://doi.org/10.1016/S0006-3207(02)00164-7
Rushworth I, Wakelin J, Bawden G (2007) Lappet-faced Vulture (Torgos tracheliotos) breeding in Ithala Game Reserve, KwaZulu-Natal, South Africa. Vulture News 57:65–67
Rushworth IA, Druce D, Craigie J, Coverdale B (2018) Vulnerability of vulture populations to elephant impacts in KwaZulu-Natal. Afr Biodivers Conserv 48:1–10
Safford R, Andevski J, Botha A, Bowden CG, Crockford N, Garbett R, Margalida A, Ramírez I, Shobrak M, Tavares J, Williams NP (2019) Vulture conservation: the case for urgent action. Bird Conserv Int 29:1–9. https://doi.org/10.1017/S0959270919000042
Shanee N (2012) Trends in local wildlife hunting, trade and control in the Tropical Andes Biodiversity Hotspot, northeastern Peru. Endangered Species Res 19:177–186. https://doi.org/10.3354/esr00469
Thondhlana G, Cundill G (2017) Local people and conservation officials’ perceptions on relationships and conflicts in South African protected areas. Int J Biodivers Sci Ecosys Serv Manage 13:204–215. https://doi.org/10.1080/21513732.2017.1315742
Vetter S, Goodall V, Alcock R (2020) Effect of drought on communal livestock farmers in KwaZulu-Natal, South Africa. Afr J Range Forage Sci 37:93–106. https://doi.org/10.2989/10220119.2020.1738552
Virani MZ, Kendall C, Njoroge P, Thomsett S (2011) Major declines in the abundance of vultures and other scavenging raptors in and around the Masai Mara ecosystem, Kenya. Biol Conserv 144:746–752. https://doi.org/10.1016/j.biocon.2010.10.024
Whelan CJ, Wenny DG, Marquis RJ (2008) Ecosystem services provided by birds. Ann N Y Acad Sci 1134:25–60. https://doi.org/10.1196/annals.1439.003
Williams VL, Cunningham AB, Kemp AC, Bruyns RK (2014) Risks to birds traded for African traditional medicine: a quantitative assessment. PLoS ONE 9:e105397. https://doi.org/10.1371/journal.pone.0105397
Wyndham FS, Park KE (2018) “Listen Carefully to the Voices of the Birds”: A comparative review of birds as signs. J Ethnobiol 38:533–549. https://doi.org/10.2993/0278-0771-38.4.533
Acknowledgements
We are grateful to the South African National Biodiversity Institute (ZA) for funding this study. Valuable input from this study’s steering committee, which included Tony Cunningham, Steve McKean, Michele Pfab and Chris Kelly, is highly appreciated. Many thanks to the study participants for their time and accommodation. We thank all the research assistants for their dedication to this work. The support received from the University of KwaZulu-Natal (ZA), WildlifeAct (ZA), the National Research Foundation (ZA, Grant 98404) and the Ford Wildlife Foundation (ZA) is greatly appreciated. We are grateful to the reviewers whose constructive comments improved our manuscript.
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All authors conceived the research idea. JS and CTD sought funding. NSM collected the data. NSM analysed the data. NSM drafted the manuscript, and all authors provided comments and revisions to the manuscript.
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Manqele, N.S., Selier, S.A.J., Taylor, J. et al. Vulture perceptions in a socio-ecological system: a case study of three protected areas in KwaZulu-Natal, South Africa. J Ornithol 164, 789–801 (2023). https://doi.org/10.1007/s10336-023-02075-7
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DOI: https://doi.org/10.1007/s10336-023-02075-7