Looking into the possibility of recovering gold from the tailings of a disused mine in Limpopo Province, South Africa.

Gold exports are a major source of revenue for South Africa, but the costs of gold production have risen in recent years, as many of the largest mines are forced to excavate ever further underground due to dwindling resources at shallower depths. At the same time, the country is littered with former mines, which closed down years ago, when methods of extracting gold from ore were less advanced, with the effect that rocks that would be seen today as viable ores were rejected as waste. This has raised the possibility that the tailings (waste tips) of these former mines could be revisited, as a potential source of workable ore. 

One such site is the Louis Moore Mine, close to the village of Ka-Mavalane in the Mopani District of Limpopo Province, which opened in 1886, when the area was part of the Zuid Afrikaannsche Republick, and closed down during the Second Anglo-Boer War of 1899-1902, not re-opening after the war due to the discovery of the much more lucrative goldfields of the Whitwatersrand. The mine accessed a fragment of greenstone belt remnant, probably derived from the Giyani Greenstone Belt (formerly known as the Sutherland Greenstone Belt), located in an area of high-grade metamorphic gneisses. The geology of the area is complex, although it has never been properly mapped. The ore body accessed by the mine targeting quartz veins in tremolite schists, amphibolites, and granitoid gneisses, probably associated with shear zones cutting across the area. Mine tailings at the site are known to be rich in arsenic, in the form of arsenopyrite, something common in shear-zone associated gold deposits.

 

The approximate location of the Louis Moore Mine, in Limpopo Province, South Africa. Google Maps.

In a paper published in the Journal of the Southern African Insitute of Mining and Metallurgy in July 2021, Ndinannyi Kenneth Singo and Jan Kramers of the Department of Geology at the University of Johannesburg examine the possibility of extracting useful amounts of gold from tailings at the Louis Moore Mine.

The tailings dump at the Louis Moore Mine measures about 100 m x 200 m. Singo and Kramers drilled ten boreholes into this site using a hand auger, taking samples for analysis at metre intervals. This yielded a total of 47 samples for analysis, as the dump deposits were less than 5 m thick in places.

The samples were found to have a pH range of 7-9, with an average of 8. This is thought to be due to the presence of dolomite in the tailings. Such a high pH level is not ideal for plant growth on the site, as alkaline soils can inhibit nutrient uptake, but also makes acid drainage, often a problem with old mine tailings, far less likely.

Four of the samples were chosen, at random, for X-ray diffraction analysis at the Council for Geoscience in Pretoria, in order to assess their mineral content. All of these had contained quartz, with three also containing dolomite, amphibole, serpentine, mica, and smectite, while the fourth contained significant amounts of plagioclase and clinochlore. This implies that the rocks being mined were not uniform during the initial excavation, with different gold-hosting rocks being targeted over the mine's history, although all of the rocks found are typical of greenstone belt lithologies and granodiorite intrusions. No jarosite was found, a mineral often associated with acid mine drainage, which makes it likely that the ores targeted had a low sulphide content. The high dolomite content seen is unusual, but carbonates have been found in association with gold deposits in other ore bodies associated with the Giyani Greenstone Belt.

A number of other metals are commonly found in association with gold deposits. These include arsenic, a toxic metal which can cause damage to the nervous system, skin, liver, lungs, and heart, as well as a range of cancers; chromium, which is highly toxic in its hexavalent form; lead, a toxic metal which bioacumulates in the body and can cause damage to the brain and nervous system, as well as developmental issues in children; copper and nickel, neither of which bioacumulate, but both of which can be toxic in high doses; and uranium, which does bioacumulate, and is radioactive as well as causing damage to the lungs and kidneys.

Significant levels of uranium are not present in the Louis Moore Mine tailings, but these deposits do show significantly raised levels of arsenic, as well as the presence of cadmium, chromium, copper, nickel, lead, and zinc. Of these, cadmium and lead are present at levels considered acceptable for soils in South Africa, while copper and zinc are at levels only slightly above these limits. However, chromium, nickel, and arsenic are found at levels significantly higher than is considered safe.

The distribution of the arsenic is not even. Most of the boreholes yielded no detectable arsenic, one produced high levels from the top two metres of spoil, and three produced high levels from the entire profile. There seems to be no horizontal zonation of arsenic, although their is a strong correlation between arsenic distribution and phosphorus distribution, with the boreholes that produced high arsenic levels also being high in phosphorus. This would suggest the presence of oxidising conditions, under which circumstances arsenic and phosphorus oxyanions (i.e. arsenates and phosphides) will tend to be precipitated out with iron oxides and hydroxides. This in turn suggests that these two elements were in solution in a tailings pond on the site where the dump now stands, which could lead to localised concentrations of these elements. One of the boreholes containing high arsenic and phosphorus also yielded stagnant water. This could imply that it was a low point during deposition, which would explain the deposition of concentrated soluble ions here. Arsenic is immobile in neutral or moderately acidic soils, but becomes mobile at pHs of less than two or greater than nine, the latter being the current upper limit for soils at the site. Due to this possibility of arsenic mobilisation, Singo and Kramers strongly recommend local communities avoid taking water from close to the dump site. 

Copper, nickel, lead and zinc can also be leached from soils fairly easily, again being reasonably stable at neutral pHs, but becoming mobile as the pH creeps above nine, when they form metal hydroxide complexes. Chromium VI, the oxidised form of chromium, also becomes mobile at pHs above 9, which could present a serious environmental problem for the Louis Moore Mine site. However, it is quite possible that the chromium at the dump is bound in silicates or oxides, in which case it would not be mobile under most natural circumstances, although it would have been freed when the rock samples were dissolved in aqua regia for analysis.

The distribution of gold within the tailings deposits is also generally homoginous, with no clear signs of layering. Gold was present at levels as high as 1 part per million in all of the samples, which suggests the original gold recovery methods were somewhat inefficient, and presents the distinct possibility that economic amounts of gold could be recovered from the tailings with modern methods, although further geometallurgical analysis would be needed to confirm this. The samples have an average gold content of 0.000 037%. Potentially, removing the tailings from the site to process them for gold could also help to remediate the site, making it available for other uses.

Mine tailings are not natural deposits, and methods used to explore natural deposits may be less reliable in this type of environment. Nevertheless, the lack of any horizontal deposition pattern being observed for any of the elements suggests that the lack of this seen for gold is a reliable finding. However, concentrations of gold do vary across the site, presumably driven by seasonal changes to the climate, changes in the level of mining activity, and variations in the quality of the original ore body.

Next Singo and Kramers used the data from ground surveys and drill cores to create a three-dimensional block map of the Louis Moore Mine dump. This used bottom surfaces determined from the depth at which the cores encountered non-dump sediments beneath the site.

 

A starting basin showing solid modelled surfaces for the topography of the Louis Moore tailings dump (grey surface indicates tailings). Singo & Kramers (2021).

No density measurements were taken during the sampling stage, but Singo and Kramers assumed a density of 1.4 kg/m³, which is safely lower than Witwatersrand gold ores (2.74-2.77 kg/m³), greenstone schists and gneissic rocks (2.6-2.9 kg/m³), and banded ironstones (3.6 kg/m³), thereby providing a conservative estimate of rock density. The dump site covers 43 000 m², and has an estimated volume of 387 000 m³; or 541 800 kg of rock. If this has an average gold content of 0.000 037%, then this equates to about 200 kg of gold, with a value of slightly over US$11 500 000 at current prices.

There is currently no evidence for acid mine drainage emitting from the Louis Moore Mine dump, probably due to the site's high pH, but the high arsenic levels present clearly do present a problem for local communities, particularly as arsenic can be mobilised under alkaline conditions. Copper, nickel, lead, and zinc are also present, and can also be mobilised in an alkaline state, but the pH is probably not high enough for this to be an issue. Chromium VI is also present, and can be mobilised at the pH levels of the site, but is probably bound into minerals that prevent its easy dissolution. The main hazard from the site is probably wind-borne dust, which has the potential to reach nearby communities and is easily ingested. Remedial processes to prevent this should include slope stabilisation, the planting of vegetation to help stabilise the soil, or covering the site with a 'cap' of clay or similar material. Alternatively nearby communities could be relocated, but this would probably be more expensive than remediating the site.

Another possibility is to exploit the site for the gold still contained within the mineral reserves. If this were done (and further testing would be necessary to confirm this is an economically viable proposition), then water sluices could be used to damp down the site and prevent dust from escaping while operations proceed; there is a river close to the site which could provide water for this.

Any attempt to reuse the land should have an end plan which includes the rehabilitation of the site. Once usable metals have been exploited from the site, the location could be repurposed in a number of ways. For example, the site, which is elevated, could be used to host a wind or solar energy facility, or simply as a suitable construction site for an extension of the village. In a addition, the mine site itself is over a hundred years old, and would qualify as a heritage site under the terms of the National Heritage Resource Act, 1999.

The site would require considerable further investigative work before it could be redeveloped, however, much of this work would be within the grasp of students of geology or mining engineering, making the site a potential educational resource, as well as a mineral one.

If the site is excavated, then much of the material extracted will have clay-like properties, and could potentially be used as a building material by local communities, and the extraction process itself could provide employment to the local community, although extreme care would be needed to contain the heavy metals within the site, and prevent them from contaminating nearby land or water.

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South African woman dies after being attacked by Crocodile.

A South African woman has died in hospital several days after being attacked by a Nile Crocodile, Crocodylus niloticus. Mavis Mohlala, 39, was attacked at about 7.00 pm on Saturday 5 October 2019, while crossing the River Lepelle (Olifants) on her way to a church service in Kolokotela Village in Limpopo Province. The Crocodile was beaten off by fellow churchgoers with sticks before she could be dragged away, and Ms Mohlala taken to the Matlala Hospital for treatment, where she died on Wednesday 9 October. Her family have raised concerns about her treatment at the hospital, and in particular why she was not transferred to the better equipped Mankweng Hospital in Polokwane, where they believe she would have received better treatment. Villagers in Tsimanyane Village, where Ms Mohlala lived, have been campaigning for a bridge to connect them to Kolokotela for several years.

A Crocodile on the Boshielo Dam Reservior on the Lepelle River, close to the Tsimanyane/Kolokotela crossing. Botha (2005).

Conflicts between Humans and animals present a major challenge in conservation work, particularly where animals are prone to attacking Humans or livestock. The most common perpetrators of such attacks in Africa are Crocodiles. Nile Crocodiles are particularly dangerous, with the largest males reaching around five metres in length, and a diet that includes animals such as Wildebeest, Connochaetes spp., and Buffalo, Syncerus caffer, species which it requires considerable strength to subdue. Crocodiles are extremely versatile in their environmental tolerances; they are semi-aquatic, but dwell in a range of habitats from large, fast flowing rivers to small ponds, and have quickly colonised Human-made environments such as canals, dam lakes and even irrigation ditches, creating extra opportunities for conflict with Humans.

Nile Crocodiles are considered to be of Least Concern under the terms of the  International Union for the Conservation of Nature’s Red List of  Threatened Species, but are still protected in many countries, due to historic hunting which decimated populations in many areas. However, the rising number of attacks on Humans by the animals has led to calls for regulated hunting to be introduced to control the population.

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Investigating Crocodile attacks in South Africa and eSwatini.

Conflicts between Humans and animals present a major challenge in conservation work, particularly where animals are prone to attacking Humans or livestock. The most common perpetrators of such attacks in Africa are Crocodiles, with two species, the Nile Crocodile, Crocodylus niloticus, and the West African Crocodile, Crocodylus suchus, together coming the overwhelming majority of wildlife attacks on the continent. Nile Crocodiles are particularly dangerous, with the largest males reaching around five metres in length, and a diet that includes animals such as Wildebeest, Connochaetes spp., and Buffalo, Syncerus caffer, species which it requires considerable strength to subdue. Crocodiles are extremely versatile in their environmental tolerances; they are semi-aquatic, but dwell in a range of habitats from large, fast flowing rivers to small ponds, and have quickly colonised Human-made environments such as canals, dam lakes and even irrigation ditches, creating extra opportunities for conflict with Humans. Despite the obvious hazards presented by Crocodiles, there have been very few organised studies of their behaviour and conflict with Humans.

In a paper published in the journal Orynx on 11 July 2019, Simon Pooley of the Department of Geography at Birkbeck University of London, the School of Life Sciences at the University of KwaZulu-Natal, and WildCRU at the University of Oxford, Hannes Botha of Scientific Services at the Mpumalanga Tourism and Parks Agency, and the Department of Biodiversity at the University of Limpopo, Xander Combrink of the Department of Conservation Science at the Tshwane University of Technology, and George Powell of the Department of Life Sciences at Imperial College London, present the results of a study of reported attacks on people by Nile crocodiles in South Africa and eSwatini (Swaziland) during the period 1949-2016.

Nile Crocodiles, Crocodylus niloticus. AFP/Getty Images.

The study area included north-eastern South Africa, including the warmer, low-lying (lowveld) region of the interior confined mainly to Limpopo and Mpumalanga Provinces, and northern KwaZulu-Natal Province, and the lower-lying warmer areas of eSwatini. Nile crocodile distribution in the region is limited to the warmer, summer rainfall regions of these countries, with the hot and wet season (with minimum temperatures above 15°C) during October–March (November–March in the interior of South Africa). Most of the rivers flow eastwards, from the central plateau and eastern escarpment to the Indian Ocean.

North-eastern South Africa and eSwatini (Swaziland), with the provinces of South Africa, key protected areas, rivers in which Crocodile attacks have occurred, and the locations of fatal and non-fatal attacks. Dams shown on the map are: (1) Makuleke Dam, (2) Middle Letaba Dam, (3) Flag Boshielo Dam, (4) Rust de Winter Dam, (5) Loskop Dam, (6) Driekoppies Dam, (7) Pongolapoort Dam, and (8) Goedertrouw Dam. Pooley et al. (2019).

The political landscape, and therefore land use, in South Africa changed radically over the period of the study. From 1949–1992 South Africa’s black African majority was persecuted under the system of Apartheid, with resettlement in remote rural homelands with poor land and few jobs, and men working in cities as migrant labourers. This system kept two-thirds of the population rural (some of them more likely to encounter crocodiles) until the early 1980s, when Apartheid began to fail. Apartheid influx laws were defied, and urbanisation accelerated, especially after an African National Congress-led government came to power in 1994. Employment in the agricultural sector is now low (5.6%) and declining, with unemployment much higher in rural areas. Census data from the Apartheid era are considered to be highly questionable, and the borders of magisterial districts varied
across the study period, and estimates of human population density exist only at a coarse scale.

eSwatini is a small, stable absolute monarchy with a largely rural population. The population increased sixfold during the study period. eSwatini is categorised as a lower middle income country, and the majority of Swazis are poor, with an estimated 70% of the population employed in subsistence farming. Many Swazis depend on rivers for water, for drinking, cooking and washing.

There are naturally occurring wild Nile crocodiles as far south as the Zinkwazi River in South Africa but the major viable populations are restricted to three disjunct protected areas: the eight large seasonal and perennial rivers traversing Kruger National Park in Limpopo and Mpumalanga provinces; and in KwaZulu-Natal Province, in Ndumo Game Reserve and the Lake St Lucia estuarine system.

A Nile Crocodile in the Kruger National Park. Trover.

Crocodile abundance in Kruger National Park peaked in the early 1990s and then declined during 1993-2000, but has since increased to an estimated 4300 individuals more than a metre in length. This is despite die-offs since 2008, caused by the nutritional disease Pansteatitis (Yellow Fat Disease). In Limpopo and Mpumalanga provinces, outside the Park just over 600 individual Ceocodiles were counted in the 1980s, most under three metres in length, with breeding populations in the Olifants, Limpopo, Luvuvhu, Komati and Blyde rivers. By the end of the study period only the 12.8 km² Flag Boshielo Dam on the Olifants River retained a viable Crocodile population outside Kruger National Park in Mpumalanga Province, and this population declined by 27% following the raising of the dam wall by5 m in 2006.

In northern KwaZulu-Natal Province, populations declined after World War II as a result of hunting and snaring, as well as habitat destruction and water shortages caused by the expanding agriculture and forestry sectors. A Crocodile restocking program was started in 1966 by naturalist and conservationist Tony Pooley, and legal protection for Crocodiles introduced in1969, resulting in a significant population recovery by the 1990s. However, the Ndumo Game Reserve population decreased by 38% during 1993-2000, possibly because of an increase in illegal killings and disturbance facilitated by the removal of the eastern boundary fence in May 2008, and in 2009 the population stood at 536 Crocodiles.

Lake St Lucia estuarine system in northern KwaZulu-Natal was restocked with juvenile Crocodiles during the period 1967-1976. The first aerial survey of Crocodiles in the lake in 1976 found a population of 356 animals more than a metre in length, and by 1993 this had risen to 975. The population remained stable until 2008 but has since declined, possibly as a result of prolonged drought.

A Nile Crocodile on the shore of Lake St Lucia. iSimangaliso Wetland Park.

With the exception of the 132 km² Pongolapoort Dam in KwaZulu-Natal declines have been reported for all major crocodile populations in South Africa. As a result, Nile crocodiles are categorised as Vulnerable in the country.

In eSwatini, extensive habitat has been converted for agriculture, and illegal hunting remained rife into the 1980s. In 1992 King Mswati III ordered a new draft of the Game Act, which introduced the
first legal protection for Crocodiles outside protected areas. No Crocodile population data are available for eSwatini, but the species is considered to be Vulnerable there.

Ezemvelo KZN Wildlife is the responsible authority in KwaZulu-Natal, South Africa. They remove rather than kill Crocodiles whenever possible, and do not erect or maintain protective structures, or pay compensation for attacks outside protected areas. The Mpumalanga Tourism and Parks Agency and Limpopo Province’s Department of Economic Development, Environment and Tourism deal with attacks in the interior. Crocodiles are protected under provincial conservation legislation.

In Mpumalanga problem crocodiles are trapped and released in either the Loskop Dam or Flag Boshielo Dam, or sold to commercial farms. The Limpopo authorities have issued tenders licensing trophy hunters to control damage-causing Crocodiles but few have been destroyed in this way. Fences have been built at some dams.

Ezemvelo KZN Wildlife Conservation Manager Mpume Ngcobo, of the St Lucia Crocodile Education Centre, releasing hatchlings into the protected kuNkazana Stream within the Eastern Shores section of the iSimangaliso Wetland Park. iSimangaliso Wetland Park.

In eSwatini, Big Game Parks is mandated by the office of the King to manage wildlife in the royal parks and outside protected areas. Their policy is to capture and remove confirmed problem crocodiles. No protective structures are built, and compensation is not paid.

Information on attacks by Nile crocodiles was obtained from the personal archives of conservationists Tony Pooley and Ian Player, the St Lucia Crocodile Centre, and the Times of Swaziland archive in Mbabane, eSwatini. Pooley et al. newspaper reports (print and online), journals and popular magazines, using the search term ‘crocodile’ paired with ‘attack’, ‘bite’ or ‘victim’, in English and Afrikaans.

Only details of attacks by wild crocodiles that resulted in injury or death were included. Alleged attacks that were not witnessed or that lacked forensic proof were excluded. Fatal attacks include attacks from which victims died later as a result of injuries sustained. Demographic categories for age
were child (under 16 years) and adult (16 years or older); sometimes exact age data were missing but victims were described as children or adults, and five year age categories were used for cases for which exact age data were available.

Crocodile attacks prior to 1949 were excluded because of a paucity of reliable data. It is likely that during the study period some attacks involving minor injuries went unreported. In remote regions, particularly areas to which people were relocated by Apartheid authorities, some serious attacks may have gone unreported.

A Nile Crocodile in eSwatini. Günther Eichhorn/Mlilwane Wildlife Sanctuary.

The literature searches returned 132 print newspaper stories and six magazine features for South Africa, and fifteen print newspaper stories of attacks in eSwatini. Sixteen online stories were retrieved through Google searches and searches of digital archives of five South African newspapers (in English and Afrikaans), and nine stories from the digital archives of two Swazi newspapers. Tony Pooley’s archive included personal records of 73 attacks in the study region, and Ian Player’s archive included 15 newspaper reports of attacks.

Overall the dataset comprises 214 crocodile attacks for the period 1949-2016: 185 attacks in South Africa and 29 in eSwatini. In South Africa, attacks have been recorded in 13 district municipalities but only five districts have more than five attacks recorded.  The majority of crocodile attacks occurred in natural water bodies with 50% of attacks in rivers or streams, 15% in lakes or pans, 3% in the St Lucia estuary, and 1% in wetlands, while 8% of attacks occurred in in dam lakes of various sizes, and 2% in canals or drains. The location of one attack was not given in the reports.

Crocodile attacks seemed to be closely related to season, with attacks far more common in the warm wet summer than in the cool dry winter. Three possible explanations for the seasonality of Crocodile attacks have been previously proposed: (1) increased Crocodile dispersal and encounter rates resulting from high rainfall and water levels, (2) Crocodiles are ectothermic and thus more active when it is warmer, and (3) increased aggression during the breeding season, Pooley et al. found that Crocodile attack incidence tracks high mean water levels (where data exist) and high monthly mean rainfall (particularly in the interior of South Africa), but that there is no significant relationship between individual attacks in the study region and high rainfall and water-level conditions recorded for dates of attacks only. They also note that previous studies have suggested that Crocodile attacks are more common in the dry season in neighbouring Mozambique.

A Crocodile in the Kruger National Park. flowcom/Flikr/Wikimedia Commons.

Monthly mean daily temperature is the strongest environmental predictor, with most attacks occurring at temperatures of at least 16°C. This effect of temperature could be explained by Crocodiles’ decreased physiological maintenance costs under cooler conditions and, conversely, increased activity levels and food requirements under warmer conditions.

The seasonality of crocodile attacks cannot be explained based on biophysical variables and Crocodile behaviour alone because of the overlap between Human and Crocodile activity (e.g. the seasonality of aquatic activity of both Crocodiles and people). Nearly half of attacks in the study region occurred on weekends and holidays, suggesting Human activity patterns are influential. Although the climate varies slightly between the interior and the coastal regions where crocodiles occur, the peak attack season is the same, December to March.

More data on local behaviour patterns of Crocodiles and people in hotspots for Crocodile attacks would contribute to more effective mitigation measures. For instance, it is known that Crocodiles congregate in lakes in Ndumo Game Reserve and on the eastern shores of Lake St Lucia in winter. Larger individuals disperse outside the protected areas or around the lake system in the summer. Thus in recreational areas around the Lake St Lucia system, notably the estuary, there are seasonal overlaps between the distributions of larger Crocodiles and people.

Nesting Crocodiles on the cliffs at Pongolapoort Dam, Northern KwaZulu-Natal. Champion (2010).

One hundred and ninety records include the activity the victim was engaged in when the attack occurred. Of these, most victims (29%) were attacked while swimming or bathing, followed by fishing (22%), doing domestic chores at the water’s edge (18%), crossing the water (16%), or other (13%). 65% of the victims of Crocodile attacks were male, and 45% female. Of the 139 reports including exact age information, 68% attacks (49%) were on adults (aged 16 years or older), and 71 attacks (51%) were on children (under 16 years). A greater proportion of the attacks on children were fatal (54%), compared with adults (35%).

The finding that it is mostly males that have been attacked in this region contradicts the assumption that in Africa women and girls are disproportionately at risk because of their domestic tasks at the water’s edge. The numerous attacks on females, most performing domestic chores, along the Pongola floodplain system in the 1960s and 1970s are atypical. Census data reveal a higher proportion of women than men resident in this region in this period, with men away working as migrant labourers. Pooley et al.s data show that domestic chores have been a less important factor in the wider region since around 2000, reflecting both the Crocodile’s contracting range and improved water provision in some rural areas.

A key finding is that 51% of victims were aged 0-15 years. That 62% of victims were aged 0-20 and the largest adult category was 21-30 (19%) may simply reflect the demography of the country (median age 26). Nevertheless, the high proportion of children, especially aged 11-15 years, 72.5% of whom were boys, suggests this should be a focus for concern and education.

The overall fatality rate from attacks was 49%, however, 57% of attacks on children (0-15 years) were fatal and 54% of victims aged 0-20 years were killed, in comparison with 40% of attacks on those aged at least 21 years. Fatality rates were influenced by whether the victim was accompanied or alone, and the size (length) of crocodile involved, as well as the size of the victim. Smaller victims (children) are more vulnerable to fatal attacks. Pooley et al. found that, of those adults who escaped death, 43% (22) escaped without help and 43% (22) were rescued, whereas only 35% (11) of children escaped unaided and 65% (20) were rescued.

Only 15 crocodiles involved in attacks were measured accurately, and therefore size data could not be used as an accurate variable. Furthermore, most Crocodile counts have been made from fixed-wing aircraft, so there are no general data on the size of Crocodiles to facilitate comparison of the number of fatal attacks with the proportion of large Crocodiles in wild populations. Comparing the length of crocodiles with fatality/non-fatality outcomes is complicated by age and size of victim, and whether there were rescuers present. Better data would be required to assess the relationship between size and deliberate attacks on people by Crocodiles in this region, although data from Alligators and Saltwater Crocodiles suggest that individuals measuring more than 1.8 m can inflict serious injuries, and individuals measuring at least 2.4 m carry out fatal attacks.

Overall, most victims were swimming, bathing or fishing, but desegregating data on activity of victim when attacked by age and gender reveals distinct profiles. Pooley et al.'s data show that until the 1980s most victims were performing domestic chores or crossing water when attacked, but since then these activities have been superseded by swimming and fishing.

Pooley et al. make several recommendations on how the risks associated with living with Crocodiles in South Africa and eSwatini could be mitigated in the future. For high risk areas there are a number of mostly low-cost actions that can be taken. Local authorities could facilitate safe water crossings, and safe access to water for swimming (particularly near rural schools) or domestic needs, including alternatives such as water tanks, piped water and protective enclosures. Provincial conservation authorities and district municipalities could create, equip and train teams to capture and remove problem Crocodiles. Where such teams already exist, it would be helpful to make them known to the public. If departmental resources are limited, a system of licensing private individuals (as in the USA) could be trialled. Some commercial Crocodile farmers already provide this service on an ad hoc basis. Removing Crocodiles requires the creation of clear protocols for disposing of captured Crocodiles.

Educating children should be a priority, particularly in identified high-risk areas. Outreach activities could be supported with existing materials that provide information on crocodile biology and behaviour, their ecological and conservation importance, as well as advice on avoiding and responding to attacks.

Provincial conservation authorities should appoint knowledgeable spokespersons to brief the public in the event of a Crocodile attack (or alleged attack). The accuracy of reporting would be improved by keeping detailed records of attacks, and building better communication between police, coroners and conservation authorities to ensure accurate information on causes of death are reported. In South Africa,where Crocodiles are farmed but not ranched (i.e. captive bred but not sourced from the wild) and there is no link between farming and the country’s wild populations of Crocodiles, and in a region where taboos against the eating of Crocodiles have recently been overturned, tolerance for wild Crocodiles should not be taken for granted.

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Security guard at South African mine killed by Elephant.

A security guard has died after being trampled by an Elephant at a mine in Limpopo State, South Africa, on Saturday 8 June 2019. Eric Kgatla. 45 was last seen in a guard house at the Foskor phosphate mine in Phalaborwa at about 4.00 am, by another guard who then went on to patrol a road at the site. The other guard returned to the site after hearing an Elephant, and witnessed one moving away from the structure, but was unable to find Kgatla. A search of the area found his body nearby, having apparently been trampled to death.

 'Guard Houses' used at the Fosker Mine. Letaba Herald.

The population of South Africa has risen from 18 million in 1960 to  57 million today, fuelling an expansion of both urban and agricultural land use into former wilderness areas. Many animals will simply flee such incursions, or, if unable to, are likely to end up in the cooking pots of hungry villagers. Elephants, however, are a somewhat different proposition. They are large animals, not used to being challenged by other animals in their home ranges, and typically live in matriarchal herds of up to a hundred, with herds holding large territories, criss-crossed by Elephant trails. A herd of Elephants encountering a new Human structure, particularly a poorly defended structure, are unlikely to attempt to go round it, and are quite likely to maximise the damage they cause to show their displeasure.

A herd of Elephants at the SanWild Wildlife and Rhino Sanctuary in Limpopo Province, South Africa. Louise Joubert.

Elephants are considered to be threatened across Africa, due to a combination of hunting, principally for the value of their tusks, and habitat loss, with the population across the continent thought to have dropped from 3-5 million in 1900 to about 415 000 today, and about 50% of Elephant-suitable land having disappeared since 1970. In South Africa the population trend has run the other way, with the population having fallen to a low of about 120 individuals in 1920, then risen to about 10 000 today through careful conservation management. However, while the country's extensive system of game reserves and national parks means that Elephants in South Africa face no immediate threat from habitat loss, the high black market value of Elephant ivory, combined with the high number of people living in poverty in the nation, means that Elephants are very much at risk from illegal hunting (poaching).

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Illegal miners die in disused mine in Limpopo Province, South Africa.

Two illegal miners have died in an incident at an abandoned mine between the villages of Xikukwani and Mavalane, near the town of Giyani in northeastern Limpopo Province, South Africa, on Saturday 22 September 2018. The men were discovered after local residents alerted police that they had got into trouble after entering the mine, prompting a rescue team to be sent to the site. The bodies of the two men were found in the mine, plus a third man, who was taken to hospital for medical attention and then arrested. Only one of the dead men has been identified, Patson Mbhiza, 33, from Mavalani Village.

The entrance to an abandoned mine near Giyani in Limpopo Province, South Africa, where two illegal miners were found dead on 22 September 2018. South African Police Service.

South Africa has a long history of strife over mining, largely relating to the exploitation of resources by large foreign companies and the relatively poor remuneration of mineworkers and communities that have lost land to mines, disputes that are intimately connected to the long term struggle against against the Apartheid system in the country. However illegal mining is seen as a relatively new problem, which authorities have yet to catch up with. As well as being a loss of revenue to the state, illegal mines do not comply with South Africa's environmental and health and safety laws, and can therefore present a threat to communities close to the operations, as well as miners employed at the sites, particularly if gold is being worked, since the quickest and cheapest way to separate gold from ore involves the use of (highly toxic) mercury. Aggregates (sand and gravel) used in the building industry are also considered a problem, as indiscriminate mining can lead to the destruction of natural habitats and farmland, as well as hastening soil and river erosion.

 A rescue worker at an abandoned mine near Giyani in Limpopo Province, South Africa, where two illegal miners were found dead on 22 September 2018. South African Police Service.

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Underground fire kills six at South African copper mine.

Six workers died in a fire at a copper mine at Phalaborwa in Limpopo Province, South Africa, on Sunday 15 July 2018. The incident at the Palabora Copper Mine was reportedly caused by a faulty conveyor belt, and prompted the miners to evacuate to a designated safe area and wait for a rescue team. However the rescue team were initially unable to enter the mine due to high temperatures, and were forced to wait for the mine could cool before a rescue could be attempted, at which point the miners were discovered to have died. 

Grieving relatives of six copper miners who died in an underground fire in Limpopo Province, South Africa, on 15 July 2018. Antonio Muchave/Sowetan Live.

High temperatures are not a common cause of death in mine fires, as the limited supply of oxygen usually prevents temperatures from rising too high, though as this is also the oxygen miners need to survive, low temperature fires can still be very deadly. For this reason mine operators typically install safe areas in deep pit mines, which are refuges with their own air supply where miners can wait for specialist rescue teams with breathing equipment.

This is the second recorded fatal accident at the Palabora Copper Mine this year, and brings the total number of fatalities in the South African mining industry to 56 so far in 2018. An investigation into the incident is being mounted by the South African Department of Mineral Resources, which had reportedly previously raised concerns about the safety of the conveyor belt system at the mine. The
National Union of Mineworkers has called for the families of the dead mineworkers to be adequately compensated for their loss, and accused mine management of putting profits ahead of the safety of miners.

The six men have been identified as Shaun Mashigo, 26, from Namakgale, Peter Selowa, 32, from Mashishimale, Vula Eckson Mayindi, 60, from Namakgale, Kgotso Peter Sekgobele, 29, from Maseke Moshate Village, Lebogang Elliot Maake, 37, from Namakgale., and Russel Ricardo Warne, 24, from Phalaborwa.

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