Savanna Buffalo

Savanna buffalo are mainly found in habitats with a high herbaceous biomass. In eastern and southern Africa, suitable grasses for Cape buffalo are found in several types of woodland, such as mopane (Colophospermum mopane), miombo (Brachystegia spp.), acacia (Acacia spp.) and Baikiaea spp. In West and Central Africa, savanna buffalo live in a variety of habitats ranging from typical Sahelian shrub savannas (Combretum spp., Terminalia spp, Acacia spp.) to Sudanian woodlands (e.g. Isoberlinia doka, Daniellia oliveri, Burkea africana).

Forest Buffalo

Forest buffalo are forest-dwellers, inhabiting rainforests with grassy glades, watercourse areas and mosaics of equatorial forests and savannas. This subspecies is absent (or present at very low densities) in continuous forests (Blake, Reference Blake2002; Melletti, Penteriani and Boitani, Reference Melletti, Penteriani and Boitani2007; Melletti, Reference Melletti2008).

Suitable habitats for forest buffalo are mosaics of forest with equatorial savannas or clearings, which consist of grassy vegetation and shrubs (Reitsma, Reference Reitsma1988; Blake, Reference Blake2002). Blake (Reference Blake2002) at Noubale–Ndoki National Park (NP) found high buffalo abundance close to open grassy areas with low abundance in the closed canopy forest, suggesting it is unsuitable for forest buffalo. A significant relationship between buffalo and natural forest clearings was also reported at Dzanga–Ndoki NP, where clearings were the centre of buffalo home ranges. In addition, no signs of buffalo presence were recorded over 500 m from clearings (Melletti, Penteriani and Boitani, Reference Melletti, Penteriani and Boitani2007; Melletti Reference Melletti2008). In Cameroon, buffalo rarely penetrated into the forest more than 300 m from logging roads, which were the main feeding sites for buffalo (Bekhuis et al., Reference Bekhuis, Jong and Prins2008).

Savanna Buffalo

African savanna buffalo are gregarious animals living in herds, and core members include adult females, subadults, juveniles and calves. Young females are known to maintain post-weaning bonds with their mother until the birth of their first calf, and probably longer. In contrast, young males gradually become independent, and are likely to form subadult male groups within the mixed herd. At the age of about 4–5 years (occasionally earlier), the males temporarily leave the herd to form bachelor groups of 2–20 individuals (sometimes more). The elder males (from about 10 years) sometimes permanently leave the herd, but this behaviour is not systematic (Sinclair, Reference Sinclair1977; Prins, Reference Prins and Beekman1996). Adult males competing for females leave the herd once their body condition decreases. Bachelor groups spend more time foraging and recover physical condition by foraging on patches of habitat too small and sometimes too risky for the herd, such as dense riparian woodland (Prins, Reference Prins and Beekman1996; Turner et al., Reference Turner, Jolles and Owen-Smith2005; see Chapter 6 for more details).

Savanna buffalo herd size varies across their distribution from as few as 20 to as many as 2000 individuals in the floodplains of eastern and southern Africa (Sinclair, Reference Sinclair1977; Prins, Reference Prins1989, Reference Prins and Beekman1996). In West Africa (WAP Regional Park), the mean herd size was about 45 individuals when excluding bachelor males, and the largest herds were estimated to contain about 150 individuals (Cornélis et al., Reference Cornélis, Benhamou and Janeau2011). Similar figures were reported for Central African savanna buffalo, except in floodplain areas such as Zakouma NP (Chad), where herds up to 800 individuals were observed (D. Cornélis, personal observation).

Forest Buffalo

Forest buffalo form small and stable herds of 3–25 individuals (Melletti, Penteriani, Mirabile and Boitani, Reference Melletti, Penteriani, Mirabile and Boitani2007; Korte, Reference Korte2008b; Melletti, Reference Melletti2008). Herds generally comprise several adult females with their young and one or two bulls (Dalimier, Reference Dalimier1955; Blake, Reference Blake2002; Melletti, Penteriani and Boitani, Reference Melletti, Penteriani and Boitani2007). In Lopé National Park, Gabon, the mean group size for the 18 herds was 12 ± 2 (range of means = 3–24; Korte, Reference Korte2008a). Larger herds were shown to contain a higher proportion of open habitat within their home range.

Although observations of solitary individuals (males and females) were reported, there is no evidence of the occurrence of sexual segregation in herds. Males apparently access profitable resources all year long and do not leave the mixed herds to form bachelor groups.

Savanna Buffalo Subspecies

Savanna buffalo herds exhibit HRs that generally range between 50 and 350 km² (see Table 6.1 in Chapter 6). The larger HRs are generally observed in areas where resources are spatially segregated, which forces herds to undertake seasonal movements (see below). In contrast, males living in bachelor groups use smaller patches of habitat and form smaller HRs (0.5 and 4 km²; Grimsdell, Reference Grimsdell1969; Sinclair, Reference Sinclair1977; Taylor, Reference Taylor1985; Naidoo et al., Reference Naidoo, Du Preez and Stuart-Hill2012a).

In some systems, the HR size of mixed herds increases during the rainy season and decreases during the dry season (Naidoo et al., Reference Naidoo, Preez and Stuart-Hill2012b; Roug et al., Reference Roug, Muse and Clifford2020). During the rainy season, forage and water are abundant across the landscape and herds can move freely to find productive areas, whereas water availability often limits movement during the dry season, constraining buffalo to areas close to permanent water sources. In other systems that either have abundant natural surface water or extensive man-made water networks, buffalo HR sizes will increase during the dry season as they search for optimal foraging grounds (Ryan et al., Reference Ryan2006).

Some buffalo populations migrate between seasonal HRs (Cornélis et al., Reference Cornélis, Benhamou and Janeau2011; Bennitt et al., Reference Bennitt, Bonyongo and Harris2016; Sianga et al., Reference Sianga, Fynn and Bonyongo2017), although the exact migration pattern is not always consistent across years (Roug et al., Reference Roug, Muse and Clifford2020). Some buffalo populations were shown to undertake partial migration, meaning that within a group (or subpopulation), some will be migrant and others resident (Cornélis et al., Reference Cornélis, Benhamou and Janeau2011). Some groups exhibiting intermediate or partially migratory behaviour were qualified as ‘expanders’ (Naidoo et al., Reference Naidoo, Preez and Stuart-Hill2012b).

Naidoo et al. (Reference Naidoo, Du Preez and Stuart-Hill2014) report several seasonal movements of buffalo from the Kavango–Zambezi Transfrontier Conservation Area (KAZA TFCA) that are the longest documented distances for this species. A female collared on the Kwando River floodplains in Namibia during the dry season moved 87 km west along the Caprivi Strip before returning to her dry season range, a round trip journey of >170 km. The following wet season, she again moved ~87 km south into Botswana, before returning to the same dry season range for a different >170 km journey.

The most frequent pattern of buffalo seasonal movements is the use of extensive upland woodland and savanna systems during the wet season, which support more abundant high-quality grasses. Once grasses and waterholes in wooded savannas have dried out, buffalo move to lowland habitats, such as extensive wetlands, riparian areas and lake shore grasslands where sufficient soil moisture for plant growth and green forage persists into the dry season (Vesey-FitzGerald, Reference Vesey-FitzGerald1960; Taylor, Reference Taylor1985; Prins, Reference Prins and Beekman1996; Cornélis et al., Reference Cornélis, Benhamou and Janeau2011; Sianga et al., Reference Sianga, Fynn and Bonyongo2017). During drought years, buffalo resort to eating more productive and less digestible forage in the form of tall robust grasses and sedges and even reeds. They will resort to browsing in the absence of sufficient grass (Jarman and Jarman, Reference Jarman and Jarman1973; Stark, Reference Stark1986).

For example, in Ruaha National Park (Tanzania), Cape buffalo showed strong association with habitats near dry season water sources, whereas they were distributed widely across the park during the wet season (Roug et al., Reference Roug, Muse and Clifford2020). As cool drier seasons advance, herds may move progressively towards localized concentrations of remaining suitable grazing resources and water supplies, with increasing herd size.

In W Regional Park (Burkina Faso, Benin, Niger), the movements of seven West African savanna buffalo breeding herds were monitored using GPS collars (Cornélis et al., Reference Cornélis, Benhamou and Janeau2011). In the dry season, herds were shown to range close (within 5.3 ± 2.0 km, mean ± SD) to segments of permanent rivers. At the onset of the monsoon rains, all herds but one (which had year-round access to suitable resources along the Niger River) performed a larger (35 ± 10 km) south-west movement in response to a large-scale directional gradient of primary production. Furthermore, the establishment of wet season HRs appears conditioned by a threshold (~10 per cent) in the availability of perennial grasses, underlining the key role played by this resource for buffalo.

This was also observed for wet season ranges of buffalo in northern Botswana, where buffalo favoured areas >15 km from permanent water that have the highest cover of high-quality perennial grasses (Sianga et al., Reference Sianga, Fynn and Bonyongo2017). This is likely because leafy perennial grasses facilitate maximum intake for a large-bodied herbivore that relies on a tongue-sweep strategy to increase bite size.

Several recent studies based on GPS tracking have highlighted the occurrence of one-way movements over long distances, akin to dispersion. In the KAZA TFCA, two GPS-tracked females (among 30 females and five males tracked) undertook a long-range (~200 km) dispersal from the Kwando and Kavango Rivers in Namibia towards the Okavango Delta (Naidoo et al., Reference Naidoo, Du Preez and Stuart-Hill2014). In the Great Limpopo TFCA, a total of 66 GPS collars were deployed during 2008–2013 on females (47 adults, 19 subadults; Caron et al., Reference Caron, Cornélis and Foggin2016). Among this sample, three subadults were reported to leave the HR of their herd and disperse over 90 km.

Perhaps the most remarkable long-range movements came from female adult animals tagged in Mahango National Park, Namibia that exited via a break in the park fence in 2011. Numerous sightings of these animals suggest they moved as a group from north-eastern Botswana into Khaudum National Park. From there, the animals split into two groups, with one group observed in Angola near the Kavango River, around 250 km from where they had been ear-tagged. Another ear-tagged animal was eventually shot in an agricultural area in the Otjozondjupa Region in central Namibia. This location was a staggering 500 km from where she was tagged, far outside what is considered current buffalo range in Namibia (Martin, Reference Martin2002).

Although the occurrence of large-amplitude dispersions is probably inherent to the spatial behaviour of some buffalo, it cannot be excluded at this stage of knowledge that some of these movements result from disorientation due to the anaesthesia required to fit the GPS collars.

Forest Buffalo Subspecies

HR data are limited for forest buffalo because there are few sites where direct observation is possible due to the forest habitat and the animal’s elusive nature (Blake, Reference Blake2002; Melletti, Penteriani, Mirabile and Boitani, Reference Melletti, Penteriani, Mirabile and Boitani2007; Korte, Reference Korte2008b). Melletti, Penteriani, Mirabile and Boitani (Reference Melletti, Penteriani and Boitani2007) report an HR of 8 km² for a herd of 24 buffalo at Danzga-Ndoki NP (Central African Republic). Based on seven radio-collared adult female forest buffalo at Lopé National Park, Gabon, over a two-year period (2002–2004), HRs of female forest buffalo averaged 4.6 km² with little HR range overlap (Korte, Reference Korte2008b). Space use within HRs varies with season, with a preference for marshes during the wet season (September through February) and for forest in the dry season (March through August).

Forest buffalo HRs are thus much smaller than those of the savanna subspecies. It is likely that this pattern, common to all studies, results from the spatial arrangement of suitable resources in dense tropical forest, but also to less pronounced seasonality of the environment.

Savanna Buffalo Subspecies

Thermoregulation

Buffalo generally cease feeding during the hottest part of the day and during the coolest part of the night for thermoregulation purposes. During the hottest hours of the day, mixed herds generally seek shade (Sinclair, Reference Sinclair1977). Contrary to females and young, males generally wallow during the hottest time of the day for periods lasting up to three hours. This practice is more effective in temperature regulation than the use of shade (Sinclair, Reference Sinclair1977).

In West Africa (WAP Regional Park), the daily activity patterns of buffalo herds were explored using biorhythm indices derived from GPS location data and activity sensors (Cornélis et al., Reference Cornélis, Benhamou and Janeau2011). At a daily scale, herds were equally active during night and day, and were mostly crepuscular, with two main active periods per day (dawn and dusk). Buffalo rested during the hottest hours of the day, and the duration of the resting bout was particularly marked during the hot dry season (Figure 5.1; Cornélis et al., Reference Cornélis, Melletti, Korte, Melletti and Burton2014).

Figure 5.1 Average daily activity of a buffalo cow tracked in the WAP transfrontier conservation area (Burkina Faso, Benin, Niger) from March 2007 to February 2008 (using temperature and activity sensors embedded in the GPS collar). The first peak of activity started at dawn and the second finished after dusk, both lasting on average about 3–4 hours.

Source: Cornélis, D. (2011). Ecologie du déplacement du buffle de savane ouest-africain (Syncerus caffer brachyceros). PhD, Université de Montpellier 2, Montpellier.

Forest Buffalo Subspecies

Much less is known about the movement and activity of forest buffalo compared to savanna populations. In Dzanga–Ndoki NP (Central African Republic), a study of a single buffalo herd showed that daily distances travelled by buffalo were generally very short (i.e. 500–1500 m) and were mainly restrained to clearings and surrounding areas (Melletti, Reference Melletti2008). The maximum distance travelled during a 24-hour tracking period was about 4000 m. Like savanna buffalo, forest buffalo wallow in the late afternoon; however, they spend more time in wallows during the dry season (Melletti, Penteriani, Mirabile and Boitani, Reference Melletti, Penteriani, Mirabile and Boitani2007; Korte, Reference Korte2008a).

Savanna (Cape, West and Central African) Buffalo

In savanna buffalo, optimal dietary conditions occur during the rainy season, while the end of the long dry season is a period of food scarcity (both in quantity and quality; Prins and Sinclair, Reference Prins2013). Detailed diet studies conducted in eastern and southern Africa indicated that buffalo are resource limited and constrained by a minimum dietary protein concentration of 7–8 per cent to make fermentation in the rumen possible (Sinclair, Reference Sinclair1977; Prins, Reference Prins and Beekman1996). In such a situation, buffalo thus face a trade-off of quality and quantity in obtaining an appropriate protein-to-fibre ratio in their diet (Redfern et al., Reference Redfern, Ryan and Getz2006; Ryan et al., Reference Ryan and Jordaan2012). During the dry season, savanna buffalo are generally forced to become more selective, and to partially switch their diet to browse (see below). Despite this, buffalo were reported to live at or below nitrogen requirements for prolonged periods, accounting for visibly losing body condition (Prins, Reference Prins1989; Ryan, Reference Ryan, Cross and Winnie2006; Ryan et al., Reference Ryan and Jordaan2012). In natural ungulate communities, the regulation of populations is driven by two processes: a control by available food resources (‘bottom-up regulation’) on the one hand, and a control by predation (‘top down’ regulation) on the other (Hunter and Price, Reference Hunter and Price1992). In the case of savanna buffalo, most authors agree that resources play a dominant role in the regulation of populations (Sinclair et al,. Reference Sinclair, Mduma and Brashares2003; Hopcraft et al., Reference Hopcraft, Olff and Sinclair2010).

There is moderate consensus in feeding studies on Cape buffalo about the preferred grass species. Usually species that are avoided contain low nutritious quality or the presence of aromatic oils (Prins, Reference Prins and Beekman1996). During the dry season, usual food resources are of poor quality, due to lignifications and high standing biomass. During this period, floodplain species (e.g. Leersia hexandra) and riverine forest species (e.g. Setaria sphacelata) become important. In areas with upwelling groundwater, species such as Cyperus laevigatus may also form a mainstay in the dry season (Prins and Sinclair, Reference Prins2013). Buffalo prefer grasses such as Cynodon dactylon, but may also eat broad-leaved grasses, such as Panicum maximum. Sinclair, in the Serengeti, reported that buffalo preferred soft, nutritious grass such as Digitaria macroblephora. Although there is little information on seasonal changes on diet, Sinclair (Reference Sinclair1977) analysed stomach contents and showed that Cape buffalo select more grass leaf at the end of the rainy season. Finally, Taylor (Reference Taylor1985) found that grasslands dominated by Panicum repens were the best habitat on the shores of Lake Kariba (Matusadona NP, Zimbabwe). In Cape buffalo, the diet of the different age/sex classes does not appear to differ and dry matter food intake ranges between 1.2 per cent and 3.5 per cent of body mass, similarly to other ruminants, but subject to food quality (Sinclair, Reference Sinclair1977; Prins and Beekman, Reference Prins and Lason1989).

Few studies investigated the feeding ecology of West and Central African buffalo. In West Africa (WAP Regional Park), habitat selection analysis emphasized the importance of perennial grasses (e.g. Andropogon gayanus; Cornélis et al., Reference Cornélis, Benhamou and Janeau2011). In this study, a gradient in primary production appeared to determine large-scale movements of herds at the onset of the wet season, but its action clearly was modulated by the proportion of perennials available. Buffalo herds were shown to establish early wet season HRs at locations where this proportion reached a 9 per cent threshold. At Benoué NP (Cameroon), Stark (Reference Stark1986) similarly reported a very high proportion of grasses in the diet, particularly Andropogon gayanus, which represented 51 per cent of the volume ingested in the dry season, versus 40 per cent in the wet season. At Zakouma NP (Chad), Gillet (Reference Gillet1969) noted a preference for Setaria anceps (particularly new shoots after fire) and Andropogon gayanus, but also Vetiveria nigritana. In the dry season, the unburned straws of Echinochloa obtusiflora appeared to be preferred.

Savanna buffalo are primarily grazers, but partially switch to browse when grasses become tall and lignified (Field, Reference Field1972; Leuthold, Reference Leuthold1972; Sinclair, Reference Sinclair1977; Mloszewski, Reference Mloszewski1983; Hashim, Reference Hashim1987; Prins, Reference Prins and Beekman1996). Shrub and tree leaves have been shown to contain higher protein (nitrogen) content than dry grasses during the dry season (Kone et al., Reference Kone, Richard and Guerin1990; Prins, Reference Prins and Beekman1996). As mentioned above, the contribution of nitrogen from browse facilitates the fermentation of fibrous grass in the rumen, which they eat in high quantities during the dry season. According to Estes (Reference Estes1991), the browse can represent up to 5 per cent of the total diet, but higher figures were reported in several sites (e.g. 26 per cent in dry season in Cameroon; Taylor, Reference Taylor1985). A wide range of species of shrubs and trees are consumed throughout African savanna, including Grewia spp., Heeria spp., Colophospermum mopane, Combretum spp., Capparis spp. and Piliostigma spp. (Pienaar, Reference Pienaar1969; Jarman, Reference Jarman1971; De Graaf et al., Reference De Graaf, Schultz and van der Waet1973; Taylor and Walker, Reference Taylor and Walker1978; Ryan, Reference Ryan, Cross and Winnie2006). In drier habitats in the Eastern Cape, buffalo appear to be adapted to eat woody species because grassy vegetation is scarce. In this particular habitat, during the dry season, up to 33 per cent of their diet comprises species such as Acacia sp., Plumbago sp. and Grewia sp.

In some areas buffalo can maintain or create ‘grazing lawns’ if the feeding interval is short enough (Prins, Reference Prins and Beekman1996). Evidence of this ‘returning’ behaviour has also been described for buffalo in Kruger NP and Klaserie Private Nature Reserve in South Africa (Bar-David et al., Reference Bar-David, Bar-David and Cross2009). They may also create favourable lawns in conjunction with other large herbivores such as elephants at Lake Rukwa, Tanzania (Vesey-FitzGerald, Reference Vesey-FitzGerald1960) and Benoué NP in central Cameroon (H. H. T. Prins, personal observation).

Geophagy has been reported at several sites, where clay or substrates rich in iron may explain this preference. On Mount Kenya, geophagy is reported in the bamboo belt (2100–3000 m), where clay soils are rich in iron and aluminium (Grimshaw et al., Reference Grimshaw, Cordeiro and Foley1995). This rare activity is carried out mainly by solitary individuals on Mount Kenya (Mahaney, Reference Mahaney1987). In Lent Valley in Kilimanjaro, buffalo enter into caves rich in sodium bicarbonate and chew off the soda deposits.

Forest Buffalo

Few data exist on the feeding ecology of forest buffalo because direct observations are rarely feasible in rainforest habitats. Blake (Reference Blake2002) in Noubale–Ndoki NP and Melletti (Reference Melletti2008) in Dzanga–Ndoki NP observed buffalo feeding mainly on Poaceae and Cyperaceae within clearings, in particular on Rhyncospora corymbosa, Kyllinga sp. and Cyperus sp. Blake (Reference Blake2002) also recorded several species of Marantaceae, including Marantochloa purpurea, M. cordifolia, M. filipes and Halopegia azurea. In addition, species of the Commelinaceae family such as Commelina diffusa and Palisota brachythyrsa and a species of algae (Spirogyra sp.) were recorded. Melletti (Reference Melletti2008) also found indirect signs of feeding activity on Commelina sp and Palisota sp. in the understory of Gilbertodendrum dewevrei mono-dominant forest.

Bekhuis et al. (Reference Bekhuis, Jong and Prins2008) used micro-histological faecal analysis in a two-month study to determine the diet of forest buffalo at Campo-Ma’an NP in southern Cameroon. They found that the most important part of the diet was composed of graminoids (43 per cent, with Leptochloa caerulescens representing 15 per cent of the total diet), non-graminoid monocots (21 per cent, mainly Commelinaceae such as Palisota spp.), dicotyledoneous plants (33 per cent, mainly leaves) and cryptogamous plants (3 per cent). The composition of the diet suggests that the buffalo fed mainly along logging roads and river banks (Bekhuis et al., Reference Bekhuis, Jong and Prins2008). Using a similar method at Lopé NP (Gabon), Lustenhouwer (Reference Lustenhouwer2008) and van der Hoek et al. (Reference van der Hoek, Lustenhouwer, Jeffery and van Hooft2013) found that the majority of plants consumed by forest buffalo were monocotyledons, primarily grasses (Poaceae) and sedges (Cyperaceae), with a low portion of dicotyledonous plants in the diet. In the same study area, van der Hoek et al. (Reference van der Hoek, Lustenhouwer, Jeffery and van Hooft2013) emphasized the importance of savanna habitat, noting that controlled burning is a key tool for maintaining open areas.

Thus far, no evidence of the existence of grazing lawns was found in the different studies focused on the feeding ecology of forest buffalo, even in areas of high density such as Lopé NP (L. Korte and M. Melletti, personal observations).