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An assessment of the impact of illegal artisanal gold mining on the environment in parts of Chewore Safari Area, Northern Zimbabwe

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Published 11 July 2023 © 2023 The Author(s). Published by IOP Publishing Ltd
, , Citation Jeremiah Chakuya et al 2023 Environ. Res. Commun. 5 075005 DOI 10.1088/2515-7620/ace23b

2515-7620/5/7/075005

Abstract

Illegal artisanal gold mining threatens biodiversity conservation within protected areas. The objectives of this study were to: (i) assess the environmental impacts of illegal artisanal gold mining in Chewore Safari Area (CSA) and (ii) assess trends in illegal artisanal gold mining within CSA, northern Zimbabwe. A mixed methods approach was used to collect data (i) from law enforcement records kept at CSA focusing on the period 2014 to 2021, and (ii) from field visits to areas affected by illegal artisanal gold mining. The study found that there was a gold rush into CSA with many people from the adjacent communities being arrested and prosecuted in the year 2014. A gradual decline trend in illegal gold mining activities was observed. Equipment or tools were confiscated from illegal miners including gold metal detectors. Site observations indicated destructive gold mining practices associated with visible land degradation. The study recommended increased law enforcement and awareness programmes within communities adjacent to CSA and reclamation of mined sites.

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Introduction

Artisanal gold mining is a growing threat to savanna biodiversity conservation (Bruner et al 2001, Cabeza et al 2019). In Africa (Ghana, Madagascar, Zimbabwe), efforts have been made to manage challenges emanating from the need to mine within protected areas with minimal success (Gandiwa and Gandiwa 2012, Owusu-Nimo et al 2018, Cabeza et al 2019). Most challenges emanate from economic challenges, poverty and lack of clear conservation policies (Matsa 2011, Owusu-Nimo et al 2018, Achina-Obeng and Aram 2022). Sustainable utilisation of natural resources is very critical in ensuring effective biodiversity conservation in many developing countries (Mbaiwa 2005, Gandiwa and Gandiwa 2012, Cabeza et al 2019, Achina-Obeng and Aram 2022). Minerals are some of the natural resources which form the basis of many developing countries sources of wealth. In Sub-Saharan Africa, mining forms the major economic activity, especially in rural areas (Aryee et al 2003, Hinton et al 2003, Owusu-Nimo et al 2018). Small-scale mining or artisanal mining shapes significantly the socio-economic lives of people and communities involved directly or indirectly (Aryee et al 2003, Gandiwa and Gandiwa 2012, Owusu-Nimo et al 2018). Artisanal mining targets precious minerals like gold, diamonds and any other minerals which are high in demand and in most cases over a small scale (Hinton et al 2003, Gandiwa and Gandiwa 2012, Wilson et al 2015). Small scale mining refers to individuals or small enterprises involved in mining, using rudimentary machines, with low production and in some cases moving from one site to the other depending on the mineral availability (Gandiwa and Gandiwa 2012, Owusu-Nimo et al 2018). Artisanal mining in most cases is not regulated, it is informal and in some cases, it is done illegally (Dethier et al 2019). Mining involves the use of very simple technologies, limited use of experts in planning, in some cases, it is seasonal and temporal (Dethier et al 2019). In Zimbabwe, artisanal mining is mostly driven by poverty and high unemployment challenges (Matsa 2011, Gandiwa and Gandiwa 2012). Illegal mining of gold is most pronounced in poor remote areas, major rivers and abandoned mine shafts in some towns (Aryee et al 2003, Achina-Obeng and Aram 2022). The northern part of Zimbabwe is endowed with high biodiversity and several mineral resources (Chakuya et al 2021). Chewore Safari Area (CSA) is one of the protected areas in northern Zimbabwe. Protected areas have a role to conserve natural resources which include wildlife and mineral resources (Tranquilli et al 2014).

Poaching of wildlife and illegal gold panning has been noted to be the most critical challenges within CSA (Chakuya et al 2021). In CSA, Illegal gold mining dates back to 2009 where gold illegal artisanal miners used simple hand-held tools like panning dishes, shovels, picks and hoes. Around the year 2014, the miners started using advanced equipment such as metal detectors, industrial mining compressors, crushers and the mining was intense within the protected area (Takyi et al 2021). Law enforcement has not been deterrent enough to control this type of illegal gold panning as has been reported in other studies (Hilborn et al 2006, Gandiwa and Gandiwa 2012). An upsurge in artisanal gold mining in the protected areas was mainly triggered by poverty in communal areas (Matsa 2011). Droughts, increased human-wildlife conflicts in communities adjacent to protected areas, loss of employment in both private and public sectors forced poor people to look for an alternative source of income. The easiest source of income that local communities could look for was either the collection of fruits, firewood and minerals from the surrounding protected areas. The discovery of gold in CSA by some local communities resulted in a national gold rush which attracted many illegal artisanal miners across the country to CSA (Chisango 2014).

Artisanal mining within protected areas is associated with many negative effects which compromise the sustainable conservation of wildlife and other natural resources (Andriamasinoro and Angel 2012, Hinton et al 2003, Gandiwa and Gandiwa 2012). Illegal artisanal mining in protected areas is associated with the clearance of vegetation and pollution (ground, air and water) (Asner and Tupayachi 2017). In some cases, the extraction and processing of minerals may involve the use of heavy metals such as Mercury which is dangerous to flora and fauna (Bergeron et al 2011, Gandiwa and Gandiwa 2012, Markham and Sangermano 2018). In most cases, the land is left with open pits, without being reclaimed and this triggers soil erosion, soil fertility loss and general loss of aesthetic value of the area (Prasetyo et al 2010, Eklund et al 2016). Apart from that, illegal miners are associated with wildlife poachers. Wildlife is exposed to poaching through several means such as trapping, hunting using dogs, poisoning killing using guns and spears. Management of illegal artisanal gold mining within protected areas is a cause of concern when it poses a threat to biodiversity conservation (Bruner et al 2001, Mbaiwa 2005, Gandiwa and Gandiwa 2012). CSA like many other protected areas is faced with illegal gold mining that surfaced around 2009 following the discovery of alluvial gold in some parts of the protected area. Therefore, the main objectives of the study were to: (i) assess the environmental impacts of illegal artisanal mining in CSA and (ii) assess trends in illegal artisanal gold mining within CSA, northern Zimbabwe.

Materials and methods

Study

CSA is divided into two (2) administrative areas, i.e., Chewore North and Chewore South. CSA was gazetted as a protected area (Safari Area) in 1975 (Moyo et al 2018). Chewore is approximately 220 km from Karoi town via Chirundu and Guruve road. Chewore South is bordered by Chundu Communal areas to the southwest, Kazangarare communal areas to the southeast, Chewore South to the east and Mana Pools National Park to the west (figure 1). Chewore South is approximately 1,958 km2 with four (4) hunting camps namely Chenje, Mana Angwa, Kachowe and Impi (Chakuya et al 2021). CSA lies in Zimbabwe's natural region five (v) with an annual rainfall below 650 mm and mean temperature ranges from 9 °C in July to 22 °C in December and mean maximum temperature ranges from 15 °C in July to 30 °C in December (Chakuya et al 2021, Chakuya et al 2022). The protected area has two (2) distinct geological zones which are the areas above the escarpment and the valley floor. The escarpment area is mountainous and hilly and is covered in very shallow gravelly and rocky soils (skeletal soils) while the valley floor area has deep alluvial soils which are complex due to varying deposits. The geology of the flat valley areas is predominantly Karroo sediments (sandstones, grits, and mudstones) with isolated patches of basalt (Moyo et al 2018).

Figure 1.

Figure 1. Map of Chewore Safari Area showing the geology and area affected by illegal artisanal mining.

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CSA is endowed with a high diversity of wild flora and fauna. The protected area is part of the World Heritage Site (Mana Pools National Park—Sapi Safari Area—Chewore Safari Area) due to its outstanding natural beauty and magnificent ecological and cultural qualities. Fossil remains and fossil footprints of 'Theropod' carnivorous dinosaurs of the mid-late Jurassic period have been discovered in CSA (ZPWMA Zimbabwe Parks and Wildlife Management Authority 2013). The vegetation of the area is described as well grassed miombo woodlands dominated by Brachystegia communities of the mountainous escarpment and other species such as Velvet Corkwood Velvet (Comiphora mollis) and red bushwillow (Combretum apiculatum) (Moyo et al 2018). The hilltops support Munhondo (Julbernardia globiflora), Zebrawood (Brachystegia speciformis), Prince of Wale Feathers (B. bohemii) and mountain acacia (B. glaucescens). Due to the high frequency of fires in this area, the area is dominated by grass species such as spear grass (Heteropogon contortus) and yellow thatching grass (Hyparrhenia dissoluta) and fine thatching grass (Hyparrhenia filipendula) (Moyo et al 2018).

Data collection

A mixed methods approach was used to collect data. Documentary review and participatory research design were employed following Crosmary et al (2013) and Gandiwa and Gandiwa (2012). The collection process involved: (i) retrieving law enforcement records from CSA crime registers, and (ii) field visits in all areas (rivers and streams, valleys and hills) affected by illegal mining. Records on law enforcement arrests and recoveries were readily available for the period 2014–2021. Seven years of study were selected, i.e., 2014–2021. The year 2014 was selected as the year when the gold rush into the protected area was very high. Quantitative data was obtained from historical records obtained from Zimbabwe Parks and Wildlife Management Authority database (ZPWMA, 2013). The qualitative data was obtained from ground truthing and site visits. A digital camera (Nikon D5600) was used to capture surface photographs of the mining area and this helped to complement the drone (DJI Mavic Mini) captured photographs. Images collected showed the extent of environmental damage to the ecosystem. Two field visits were made in May 2020 and September 2021 and a stretch of 30 km was assessed. Sites with signs of past and present illegal mining activities were recorded on a hand-held Garmin® eTrex® 10 Global Positioning System (GPS). A modified mining environmental impact assessment scaled table was used to analyse the impact of illegal mining within the CSA (Gandiwa and Gandiwa 2012). The scale ranged from very high impact to low impact. Very high impact referred to very high environmental risks, and direct physical environmental damages with immediate to long term effects (more than 5 years) on the environment. High impact referred to high environmental risks, direct to indirect physical environmental damages with immediate, short and long term effects on the environment. Medium impact referred to moderate environmental risks, mostly indirect environmental damages with gradual to short-term effects on the environment. Lastly, low impact referred to low environmental risks, and indirect environmental damage with short-term effects on the environment. Descriptive statistics (means, sum and bar graphs) were used to summarise trends in illegal artisanal gold mining activities within the protected area. We performed simple linear regression analyses using IBM SPSS 20 software package (IBM, New York, USA) to determine trends in illegal gold mining within CSA between 2014 and 2021. Recommendations to ensure sustainable management and control measures of illegal mining were made after assessing the root causes of illegal mining.

Results

Environmental impacts of illegal artisanal gold mining

The impacts of illegal gold mining within CSA varied from medium to very high (table 1). Some impacts were direct and others were indirect and their severity on CSA biodiversity varied. The direct impacts of illegal gold mining were on vegetation, ground and soil and most of them had high severity. Indirect impacts were on wildlife feed, wildlife distribution, aesthetic value of the land and the impacts ranged from medium to high.

Table 1. Impacts and severity resulting from artisanal gold mining in Chewore Safari Area.

Nature of impactSeverity of impact
Abandoned pit scars pose serious hazards to wildlife and park rangers in the areaVery high
Vegetation cover lossVery high
Soil profile and soil structure disruptionVery high
Wildlife feed, habitat and dispersal disturbancesVery high
Downstream water contaminationMedium
Underground water contaminationMedium
Increased risk of downstream river siltationMedium
Risk of development of unplanned infrastructures: roads, sheltersHigh
Increased disturbance to safari hunts within Chewore Safari AreaHigh
Increased pollution risks such as: water, air, noise, groundMedium

Notes: Very high- very high negative impact (very high environmental risks, direct physical environmental damages with immediate to long term effects (more than 5 years) to the environment), High- high negative impact (environmental risks, direct to indirect physical environmental damages with immediate, short and long term effects to the environment), Medium- intermediate negative impact (moderate environmental risks, mostly indirect environmental damages with gradual to short term effects to the environment) and Low- low negative impact (low environmental risks, indirect environmental damage with short term effects to the environment). Source: Fieldwork, April 2022.

Illegal mining affected an area of approximately 1.8 km2 with an approximate perimeter of 5.5 km. Illegal mining destroyed vegetation and soil profiles. Unreclaimed pits formed a great potential danger for humans and wildlife using the area (figure 2). Bare soil surfaces trigger soil erosion and siltation thus affecting the general water-holding capacities of streams and rivers within the CSA.

Figure 2.

Figure 2. Environmental degradation from illegal artisanal mining in CSA. Photo credits: N Munkuli and J Chakuya. Source: Fieldwork, September 2021.

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Trends of illegal artisanal gold mining within CSA

Three hundred and twenty illegal artisanal miners were arrested for illegally mining within CSA between 2014 and 2021. The majority (242) of the arrested illegal artisanal miners were locals from the Hurungwe district. A high illegal gold rush into CSA was recorded in the year 2014 with 136 (43%) local illegal artisanal miners and 62 (19%) non-local Illegal gold miners. From the year 2015, the number of arrested illegal miners declined to below 50 per year and this could be a result of increased law enforcement, fines and jail terms from 2014. Multiple linear regression was used to test if the arrests of illegal miners significantly predicted the number of acquitted, fined and jailed illegal miners. The fitted regression model was: Illegal miners: = 0.08 + 1.26 (acquitted) + 1.26 (fine) − 0.05 (jailed). The overall regression was statistically significant (R2 = 0.9984, F (3, 4) = 871.52, P < .000). It was found that fines issued to illegal gold miners significantly predicted the number of illegal miners (β = 1.26, p = .000). It was found that acquitted and jailed illegal miners did not significantly predicted the arrests of illegal miners with: acquitted (β = 1.26, p = 0.19) and jailed (β = −0.05, p = 0.89).

Most arrested illegal artisanal miners were fined and released (figure 3). In the year 2014, a high number of fines were issued to illegal artisanal miners. In the year 2019, there were no acquittals or fines, all arrested illegal artisanal miners were imprisoned. However, in the year 2018, there were no arrests made in relation to illegal gold mining activities within CSA.

Figure 3.

Figure 3. Action taken to arrested illegal artisanal gold miners in different years.

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Illegal artisanal gold miners came from five (5) provinces of the country (table 2). Mashonaland West province recorded the highest number of illegal artisanal miners 242 (76%) followed by the Midlands 36 (11.6%). In 2014, Mashonaland West province was on top of the illegal artisanal gold miners arrested in CSA.

Table 2. The year and illegal artisanal gold miners arrested from each province.

YearProvinceNumber of arrests
2014Mashonaland West136 (42%)
 Harare4 (1%)
 Masvingo26 (8%)
 Midlands22 (7%)
 Bulawayo10 (3%)
2015Mashonaland West21 (7%)
 Masvingo2 (0.6%)
 Midlands2 (0.6%)
2016Mashonaland West12 (4%)
2017Mashonaland West21 (7%)
2018No arrests0 (0%)
2019Mashonaland West29 (9%)
2020Midlands12 (4%)
2021No arrests0 (0%)
Total 320

Several recoveries were made between the years 2014 and 2021, however, metal detectors (35) and picks were the major recoveries recovered from illegal artisanal gold miners (table 2). In 2018 and 2021, there were no successful arrests made. In 2018 and 2021, there were 7 and 4 respectively illegal gold miners who escaped before they were arrested in the protected areas. Rangers and law enforcement officers could not trace such escapees as some raids were conducted during the night and some arrested partners protected their accomplices. Most recoveries were made in the year 2014, 2019 and year 2020 (figure 4). Metal detectors and shovels were the major recoveries for the past seven years.

Figure 4.

Figure 4. Major recoveries made from illegal artisanal gold miners for each year in CSA.

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Discussion

Most illegal artisanal gold mining operates without a land reclamation plan (Gandiwa and Gandiwa 2012, Eklund et al 2016, Achina-Obeng and Aram 2022). Illegal miners leave deep and shallow pits from the ground excavation processes. Abandoned pit scars pose serious hazards to wildlife and human in the area. Wildlife and humans may risk falling into such pits. CSA is a World Heritage site and mining may devalue the site and thus risk the delisting of the area from the World Heritage. Artisanal mining involves huge clearance of vegetation, loss of soil profile and structure and this destroys wildlife habitat and feed. Disturbances in ecological processes may for wildlife migration and poor wildlife distribution. Gold mining within a protected area affects water availability and this affects wildlife distribution and such effects affect the hunting industry within the CSA (Chakuya et al 2021).

This study shows that illegal artisanal gold mining was high in the year 2014 and gradually declined towards the year 2021. In 2020 a slight increase in the number of arrests and fines was noted and most of the arrested were non-local, this could be a result of a lack of information on security measures which were put in place inside the protected area and illegal miners unknowingly entered the protected area and got arrested. High numbers of arrests and recoveries were in the first two years after the discovery of gold within the CSA. The high gold rush into the protected area attributed to high numbers of illegal miners flocking into CSA. In some years, arrests and recoveries were low due to increased escapees and changes in ways or strategies by illegal artisanal miners. Artisanal gold mining in Zimbabwe increased between 2000–2008 due to poor countries' economic performance (Matsa 2011, Gandiwa and Gandiwa 2012, Wilson et al 2015). However, most of the gold mining was confined to remote rural areas rivers and abandoned mining shafts. Due to poverty, communities gradually straddled into protected areas in search of gold, fruits, firewood, water and other basic commodities (Matsa 2011, Kachena and Spiegel 2019, Takyi et al 2021). The discovery of gold in CSA resulted in a high gold rush into CSA thus resulting in increased illegal artisanal gold mining within the protected area. Communities adjacent to protected areas form the first line of defence against illegal entry and misuse of natural resources. Adoption of community empowerment, participation approach and intense education awareness is critical in ensuring effective natural resources protection from most forms of illegal activities. Communities need a sense of ownership of the resources and sensitised on sustainable utilisation of resources.

Law enforcement which resulted in imprisonment and fines was the main tools used to control illegal artisanal miners who were arrested. Many fines and imprisonment were recorded in the first years and gradually declined. In most cases, law enforcement groups argue for harsher fines and penalties to deter crimes. A study in Australia (New South Wales) suggested that fines and harsh penalties increase recidivism (Alexeev and Weatherburn 2022). Another study in USA (Texas), revealed that offenders who receive fines were more likely to commit additional crimes than those who were not punished. The same study revealed that offenders who receive severe fines were more likely to commit future crimes than those who receive lesser fines (Critelli and Crawford 1980). In this regard, managing crimes fuelled by poverty using fines and jail terms will be very complicated. Some cases were acquitted and some illegal artisanal gold miners escaped and were not arrested. The use of courts and issuance of deposit fines by courts or by ZPWMA entirely depends on the management of corruption and transparency. Issues around artisanal gold mining are associated with rich cartels which sometimes are difficult to be issued justice.

This study revealed that most people involved in the illegal activities were from the local communities and from Mashonaland West province. High numbers of local communities could have participated in illegal artisanal gold mining due to their proximity to the protected area. Due to proximity, local communities walked into the protected area as compared to other miners who had to travel long distances to CSA. Apart from that, due to poverty, local communities were easily recruited as trackers by non-local artisanal gold miners to help in finding the mining sites. Local communities empowerment and beneficiation of communities from the protected area are critical in ensuring crime control. Communities can be empowered financially to fund alternative sources of income sustainably for example agro-based and value-addition projects. In addition, communities can be empowered with technical expertise in handling challenges emanating from adjacent protected areas and realise benefits from perceived challenges. Law enforcement can be deterrent but it is associated with higher costs as compared to the cost of ensuring self-governance (Hilborn et al 2006, Hilson and Maconachie 2020). Resuscitation of Communal Area Management Programme For Indigenous Resources (CAMPFIRE) is critical in ensuring the protection of natural resources by creating an enabling environment which ensures local communities benefits socially and economically from the surrounding resources. CAMPFIRE concept aims at supporting and benefiting communities adjacent to protected areas in Zimbabwe by ensuring that the proceeds derived from conservation works also benefit communities adjacent to such protected areas. Beneficiation from conservation will enable communities to appreciate conservation thus ensuring a participative approach to natural resources conservation by communities (Tchakatumba et al 2019).

This study revealed common tools recovered from illegal artisanal gold miners. Earlier studies indicated that most rural artisanal gold miners used simple tools like shovels, picks, axes and holes to mine alluvial gold. In this study, a significant number of metal detectors were recovered from illegal artisanal gold miners. Deep shafts were observed in mined areas thus indicating the intensity of mining. The use of advanced technology in mining indicates that the mining activity was intense. Since mining was illegal in a protected area, artisanal miners could not use dynamites and compressors which are noisy to easily attract patrolling rangers. In this case, metal detectors were effectively used as most illegal miners searched for gold nuggets and quickly evade arrests. Miners did not use Mercury or cyanide to process their ore since the area does not have enough water and the process involves operating on one station which has a high risk of being caught by operating rangers.

Generally, Illegal artisanal mining within protected areas poses direct and indirect ecological threats (Tranquilli et al 2014). Most of the activities impacts are very unsustainable to the environment due to the unavailability of evaluated mining plans and land reclamation strategies (Achina-Obeng and Aram 2022, Amankwah and Amin-Sackey 2003). However, artisanal mining can be an essential activity to benefit local communities and national development if conducted sustainably in non-protected areas. Communities can be organised and supported with technical expertise to sustainably mine gold deposits which can be found in their communal areas not in protected areas. There are many reasons why local communities especially adjacent to protected areas get involved in illegal artisanal gold mining in developing countries (Amankwah and Amin-Sackey 2003, Prasetyo et al 2010). Economic instability and high unemployment trigger many communities to sort a living from illegal mining.

There are many factors which fuel illegal gold mining within the protected areas. The main factors include the availability of markets to purchase the illegally mined gold and the availability of other illegal supporting services (illegal shops, illegal gold buyers) to support the miners. Zimbabwe Parks and Wildlife Management Authority (ZPWMA), Rural District Councils (RDC), Non-Governmental Organisations (NGOs) and the government have a critical role to ensure local communities support (Gandiwa and Gandiwa 2012, Tchakatumba et al 2019). Communities adjacent to protected areas form the first line of defence against flora and fauna within the protected area. Support could be in the form of employment creation, education and awareness and project developments which helps to improve their standards of living (Gandiwa and Gandiwa 2012, Tchakatumba et al 2019). Local communities empowerment and support to conduct sustainable legalised mining can help to manage impacts associated with illegal mining (Hilson 2012, Tchakatumba et al 2019). Law enforcement, arrests and prosecution of illegal miners can help to protect illegal mining in protected areas, but for as long as there is poverty and a ready market for gold, challenges of illegal gold mining within protected areas may persist (Hilson 2012, Hilson and Maconachie 2020).

Conclusion

Illegal artisanal gold mining within protected areas is not sustainable for biodiversity conservation. Most of the illegal mining activities were associated with high environmental degradation. Most of the illegal mining activities posed a high threat to vegetation, wildlife and water within CSA. The small-scale illegal gold mining activities could have triggered the gold rush across the country and during the first year, the damage to the ecosystem and local communities arrests and prosecutions were high. Sophisticated machines like metal detectors and many different tools were used for illegal mining and were recovered from law enforcement operations. A gradual decline in illegal mining activities was noted after 2014. The decline in illegal mining could have been contributed by intensive law enforcement operations which prevented illegal entry into the protected area and arrests of illegal miners in the protected area. All illegal mining activities were not compatible with the functions of the CSA as a protected area and World Heritage site. Challenges associated with illegal gold mining could be addressed by local communities empowerment and poverty eradication through sustainable communities projects. The study recommends increased law enforcement and awareness to communities on biodiversity conservation. The study further recommends a land reclamation programme to be done on illegally mined areas within CSA.

Acknowledgments

We thank Dr F U Mangwanya, Director General, Zimbabwe Parks and Wildlife Management Authority (ZPWMA) for permission and support to conduct this study. We thank Mr F Chimeramombe, Regional Manager, and Mid-Zambezi Region for transport and movement logistics into the CSA. We thank the staff from Chewore Safari Area and Mid Zambezi Regional Office for their support in data collection.

Data availability statement

The data cannot be made publicly available upon publication due to legal restrictions preventing unrestricted public distribution. The data that support the findings of this study are available upon reasonable request from the authors.

Author contribution

JC designed the research and wrote the manuscript, JC, NM and CM collected field data, and EG analysed data and reviewed the manuscript.

Funding

The authors received no direct funding for this research.

Conflict of interests

The authors declare no competing interests.

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