Conflict between humans and elephants (Loxodonta africana) has been investigated throughout Africa, focusing on elephant crop raiding activities (O’Connell-Rodwell et al. 2000), mapping elephant movement patterns around human settlements (Galanti et al. 2006) and investigating possible corridors along which elephants can move safely between reserves (Van de Perre et al. 2014). However, as human and elephant populations increase, both in and around protected areas, the likelihood of interactions between humans and elephants, as well as the levels of human–elephant conflict (HEC), will increase. In southern Africa, elephants can move freely throughout the Great Limpopo Transfrontier Park (GLTP), owing to fences being dropped between South Africa's Kruger National Park (KNP), Mozambique's Limpopo National Park (LNP) and Zimbabwe's Gonarezhou National Park (GNP). However, HEC is prevalent within this region as humans and elephants share the same landscape and compete for the same resources (Dunham et al. 2010; Witter 2013). Residents have reported that the presence of elephants has placed restrictions on their livelihoods: they are scared of moving between villages and elephants raid their crops (Milgroom & Spierenburg 2008; Witter 2013). In addition, six elephants were shot within the LNP between 2006 and 2008 as a consequence of HEC (Dunham et al. 2010). HEC is further complicated by residents’ unwillingness to be moved to areas outside the GLTP (Lunstrum 2015; Milgroom & Spierenburg 2008; Witter 2013).

Global positioning system (GPS) technology has been widely used in elephant movement pattern studies since the mid-1990s (Douglas-Hamilton 1998). This technology allows scientists to track animal positions over time and relate these positions to the animals’ environment (Cagnacci et al. 2010). Animal movements are influenced by both external factors such as resource availability and internal factors such as reproductive status or fear (Nathan et al. 2008). Environmental factors such as water distribution (Smit, Grant & Devereux 2007; Thomas, Holland & Minot 2011), vegetation greenness (Marshal et al. 2011) and shifts in rainfall patterns (Birkett et al. 2012) all drive elephant movements. However, in this study we focus on how the anthropogenic environment within and around the GLTP affects elephant movement patterns. The way elephants use the areas surrounding villages will depend on their spatial and temporal knowledge of human activities, such as when crops present alternative food sources, when humans are least active or how humans react to their presence (Hoare & Du Toit 1999).

As bulls have different nutrient requirements from cows, preferring bulky diets over quality of vegetation (Greyling 2004; Shannon et al. 2006), the body size hypothesis predicts sexual segregation in bull and cow movement patterns outside of mating events (Stokke & Du Toit 2000). Cows are responsible not only for feeding the young elephants nutrient-rich milk during lactation, but also for regulating the pace of movement to that of the young elephants to ensure their safety (Duffy et al. 2011; Shannon et al. 2010). We therefore expect differences in movement patterns to occur between the sexes.

Specifically, the objectives of our study are (1) to analyse the seasonal occurrences of bulls and cows at different distances from villages, (2) to compare the distance at which bulls and cows occur relative to villages over a 24-hour period and (3) to calculate and compare the displacement rates (distance travelled by an elephant between consecutive collar recordings) of bulls and cows at different distances from villages.

We found that the majority of elephant locations in village community zones occurred during the drier months. Previous studies have suggested an increase in elephant movements around villages as a result of decreased water availability in protected reserves (Kioko, Okello & Muruthi 2006), an increase in nutrient quality available in villages (O’Connell-Rodwell et al. 2000) and a decrease in the natural vegetation quality in protected reserves (Osborn 2004). In the context of the GLTP, no single explanation can be given for the observed higher frequency of elephant locations close to villages without real-time observations during the dry season. Most of the villages are located along major river systems, including the Rio Limpopo (Limpopo River), the Rio Shingwedzi (Shingwedzi River) and the Rio dos Elefantes (Olifants River). In contrast to the neighbouring KNP, there are no artificial water points in the LNP and elephants appear to concentrate their movements through the LNP along river systems (unpublished data). Furthermore, motor and hand-held pumps have been provided to river-bordering villages in the region to enable residents to grow crops throughout the year without having to rely on rainfall (A. Alexander, pers. comm., 17 July 2014). Elephant locations close to villages may therefore be due to a combination of water being available close to the crops and crops offering accessible and diverse resources (depending on what crop type is being cultivated). During the drier months, when natural resources become scarce, elephants will be more prone to supplement their diets with cultivated crops until the nutritional quality from natural vegetation increases in the wetter months. Osborn (2004) found similar behavioural patterns for elephants in northern Zimbabwe and Witter (2013) mentions elephants utilising not only crops but also fruit grown and stored around villages in the LNP.

We found that only the bulls used the 0 km – 2 km buffer zone. Bulls have been found to be more likely to move within closer proximity to villages than cows, with hypotheses suggesting that the increased intake of higher quality crops enables the bulls to compete more successfully against other bulls for dominance status and mating opportunities (Chiyo et al. 2011; Sitati et al. 2003; Sukumar & Gadgil 1988). Although the presence of crops would also be attractive to cows and their smaller family members, the small number of cow locations in the closest community zone could simply be a result of the risk posed by humans coupled with an inability to move to safety as quickly as bulls, who generally have smaller group sizes and whose movements are not constrained to the same level by the slowest members of the group, usually calves (Duffy et al. 2011; Shannon et al. 2010). Despite the presence of smaller-bodied cows, who are often pregnant or lactating and therefore in need to maintain diets of higher quality compared to bulls (Stokke & Du Toit 2000), safety aspects may outweigh the nutrient value of the crops when considering family units. The predation-risk theory predicts that cows with young are more vulnerable to predation than bulls and are therefore less likely to use areas of potential danger (Ruckstuhl & Neuhaus 2002). The predation-risk theory may explain why elephant breeding herds are less inclined to use areas around villages in comparison to bulls, as the villages may present a potential danger to the cows and their calves. In addition, solitary bulls may be less likely to be detected by humans when crop raiding than a breeding herd with more individuals (Sukumar & Gadgil 1988). Crop raiding may therefore be a more attractive activity for solitary bulls able to avoid human observation.

The majority of elephant locations in the 0 km – 2 km and 2 km – 4 km buffer zones occurred in the evening–midnight period, which suggests that the elephants are closest to villages when humans are least active. Evening–midnight location trends have been recorded both for elephants moving past villages (Douglas-Hamilton, Krink & Vollrath 2005; Graham et al. 2009; Van de Perre et al. 2014) and for actively crop-raiding elephants (Chiyo & Cochrane 2005; Jackson et al. 2008; Sukumar & Gadgil 1988). The low proportion of locations in the community zones between midnight and early morning may be attributed to elephants moving out of the community zones during this period to rest or sleep. Rest periods are associated with less vigilant behaviour, which is easier when not in a potential landscape of fear (Wing & Buss 1970). However, more information is required based on GPS locations recorded at shorter time intervals to test for such fine-scale activity patterns of elephants.

The increased displacement rates of bulls moving through the community zones suggest that the displacement rates of elephants increase when moving through areas of potential high risk. This increased displacement rate was particularly evident in the 0 km – 2 km buffer zone, which is occupied by village infrastructure and residents. Elephants that move through a community zone with the sole purpose of minimising the time spent in that zone will be likely to have increased displacement rates as their movement patterns are more likely directional (Douglas-Hamilton et al. 2005; Jachowski, Slotow & Millspaugh 2013). If an elephant is crop raiding, its displacement rate will be lower than that of an elephant moving through in a directional manner, as the distance covered between locations will be minimal. This does not necessarily suggest that the elephant's speed has decreased (Graham et al. 2009), as a crop-raiding elephant may be moving at an increased speed amongst crops in a non-directional and tortuous manner to maximise resource intake. Therefore, the variation in displacement rates seen between bulls moving through community zones could mean that not all elephants moving through a village carry out the same activity or respond to the presence of a village in the same manner (McComb et al. 2011). Musth is known to influence the movement rates of bulls (Rasmussen, Wittemyer & Douglas-Hamilton 2005) and hence individual variability between bulls could also be linked to their reproductive status at the time of crop raiding. Although the displacement rate of the cows increased when moving through the community zones, there was no significant change between displacement rates within a buffer zone or the displacement rates of different cows, presumably as cows are equally constrained by their group sizes and can maintain movement at a constant rate when not in the highest danger zone (0 km – 2 km).

Elephants from the KNP are moving in close proximity to villages within the GLTP. This is the first known study focusing on the movement patterns of elephants around villages in the GLTP and provides baseline information on how elephants in the GLTP use the areas around villages. Elephants evidently have to play off the benefits derived from crop raiding against those of being persecuted by humans. Bulls and cows were found to handle these treat-versus-threat scenarios differently, with bulls being less risk averse than family units. Further understanding of the movements of elephant bulls and breeding herds around villages within this area requires a more in-depth approach. Focusing on the human density, crop layout, water availability and previous experience with HEC will benefit our understanding of how these factors influence elephant movement patterns. By understanding where, when and in what manner elephants are moving around these villages, conservation authorities can begin to adopt mitigation systems such as beehive fences (King, Douglas-Hamilton & Vollrath 2011) or chili extracts (Osborn & Rasmussen 1995) in an attempt to minimise HEC in the region. In addition, resettlement of villages within and around the GLTP should take place away from seasonal elephant routes to prevent conflict between humans and elephants in this region.