The significance of breeding synchrony in the wildebeest

Unlike most ungulates, whose offspring remain concealed for some time after birth, the offspring of the wildebeest and other alcelaphine antelopes (except harte-beest) accompany the mother from the very first hour. Most other ungulates that have follower-young either protect them effectively through a maternal or group defence (e.g. cattle, muskox, equids, and rhinoceroses), or are able to flee to sanc-tuaries (e.g. goats, sheep and goat-antelopes). In the Alcelaphini, primary reliance is placed on flight and on concealment among conspecifics; there is no effective defence against predators and no sanctuary. The spotted hyena is the primary predator on wildebeest calves. Over 80% of all wildebeest calves are born within an annual 2–3 week calving peak. During three different calving seasons (1 963-65) in Ngorongoro Crater, Tanzania, mortality in small, dispersed herds was found to be far higher than in large aggregations. The evidence suggested that this antelope's unusual reproductive strategy is adapted to the mobile-aggregated distribution pattern characteristic of migratory populations, rather than to the sedentary-dispersed pattern seen in resident populations. Further study on this specific question was undertaken during the 1973 calving season, with particular attention to reproductive success in small herds. Calf survival in small herds averaged just over 50% at the end of the 1973 birth peak, compared to 84% in aggregations. Daily sampling showed that calving peaked at different times in different parts of the Crater; this resulted in an extended season, although the peak in each population unit was of approximately equal duration. In some areas, calving was virtually finished before the peak began in the aggregations. Mortality ranged from very high among early calves to low in herds whose peak coincided with that of a nearby aggregation. The lack of synchrony between Ngorongoro subpopulations apparently reflects microclimatic differences, there being a pronounced rainfall and vegetation gradient within the caldera despite its small (265 km2) floor area. Low calf density combined with a lack of synchrony between small herds in different localities makes wildebeest living in the sedentary-dispersed pattern subject different localities makes wildebeest living in the sedentary-dispersed pattern subject to high calf mortality by the spotted hyena; in effect, resident subpopulations that calved ahead of the main population were providing a steady protein windfall for Ngorongoro's 470 hyenas. Tn the large aggregations, there were enough older calves to provide ‘cover’ for neonates during the first crucial day or two, making it much harder for hyenas to single out easily caught individuals. Therefore, lack of synchrony between aggregations did not apparently increase calf mortality to the same extent as it did in small herds. However, the highest survival rate was found among wilde-beest that left the Crater altogether and calved in an area with few hyenas. An evolutionary model of the wildebeest's reproductive system is presented, in An evolutionary model of the wildebeest's reproductive system is presented, which it is postulated that the system developed as part of the migratory habit of species. Given a feeding specialization for short, green grass and large, necessarily mobile aggregations, several synergistic selection pressures against concealment in favour of a follower strategy can be readily imagined. Breeding synchrony large aggregations are seen as the keys to the success of this strategy and an alternative to group defence, whereby predator populations are glutted without being sustained and the most vulnerable neonates are protected through the confusion effect created by many calves. Such a strategy is much less adaptive in a sedentary-dispersed population–which is the distribution pattern common to most antelopes-suggesting resident wildebeest populations represent a secondary adaptation to stable environments. Yet calf survival even in resident populations may equal the survival rates hidden young of sympatric antelopes, and be adaptive to the more fixed resources available in such situations.     

Black wildebeest seek shade less and use solar orientation behavior more than do blue wildebeest

Many ungulates, including wildebeest, seek shade and orient their bodies relative to incoming solar radiation in order to reduce environmental heat loads. Blue (Connochaetes taurinus) and black wildebeest (Connochaetes gnou), which co-exist artificially in some reserves in South Africa, are thought to adopt different thermoregulatory behaviors to mitigate high environmental heat loads. However, whether or not blue and black wildebeest use different behaviors to reduce heat loads in regions where they co-occur has never previously been examined. We compared the shade seeking and solar orientation behavior of free-ranging blue and black wildebeest in summer at three locations in South Africa where both species co-occur. We found that blue wildebeest exhibited more shade seeking behavior than did black wildebeest at all times of day, at all study sites. Black wildebeest remained in the sun but were more likely than blue wildebeest to orient their bodies parallel to the sun at all study sites, a behavior which reduces the amount of surface area exposed to incoming radiation. Black wildebeest were most likely to employ parallel solar orientation during the hottest times of the day when the sun was not directly overhead (i.e., solar noon ± 1 hour). We thus demonstrate that co-occurring blue and black wildebeest use different thermoregulatory behaviors to reduce high heat loads. It is possible that the lack of shade in the historical distribution of black wildebeest led to selective pressure for reliance on solar orientation. Differences in thermoregulatory behavior can affect species-specific heat loads, habitat use, body mass, fitness and grazing activity. Such differences may also allow blue and black wildebeest to inhabit separate microclimates within the same habitat, provided there is sufficient heterogeneity in vegetation structure, potentially facilitating reproductive isolation.     

Protozoa and digestive tract parameters in Blue wildebeest (Connochaetes taurinus) and Black wildebeest (Connochaetes gnou), with description of Entodinium taurinus n. sp.

Rumen contents from four blue wildebeest (Connochaetes taurinus) and six black wildebeest (Connochaetes gnou) were collected from two locations during two winter culling seasons. A total of 16 species of protozoa were found in blue wildebeest with Dasytricha ruminantium, Opisthotrichum janus and Ostracodinium gracile occurring in all four animals. In black wildebeest, 23 species of protozoa were observed with only Diplodinium bubalidis (caudal spine morphotype) and Ostracodinium damaliscus being present in all animals. In the blue wildebeest, the total number of species in an individual animal varied from 9 to 11 and in the black wildebeest, the number ranged from 4 to 14. Concentrations of cells per ml ranged from 1110 to 5880 in the blue wildebeest and 3120 to 6240 in the black wildebeest. This study is the first report on protozoa species in the blue and black wildebeest. A new species of Entodinium is described, Entodinium taurinus n. sp., observed in the rumen contents of three blue wildebeest. Several physical parameters of the digestive tract were also measured, including distribution, pH and density of gastrointestinal contents in different sections of the total tract. In vitro gas production was estimated for rumen, cecum and colon contents.     

A comparison of sex ratio,birth periods and calf survival among Serengeti wildebeest sub‐populations,Tanzania

Although adaptation and environmental conditions can easily predict demographic variation in most savannah ungulates, no study on demographic consequences arising from natural and anthropogenic factors among Serengeti wildebeest (Connochaetes taurinus) sub‐populations in Tanzania has been carried out. Here, I report estimates of annual sex ratio, calf and yearling survival rate and birth seasonality between resident and migratory sub‐populations to explore demographic patterns arising from the different age and sex structure. The results indicate significantly higher female‐biased sex ratios in the resident and almost even sex ratios among individual migrants. The calf recruitment estimated as mother: offspring ratios indicate a more synchronous birth in the migrant than the resident sub‐population. Also, birth seasonality in the migratory sub‐population coincided with seasonal variability of rainfall and the timing of the birth peak was more variable in the migrants than the resident sub‐population. The migratory sub‐population had a higher annual proportional mean calf survival estimate (0.84) than that of the residents (0.44) probably due to higher mortality resulting from predation in the western corridor. However, the proportion of yearling survival estimates was much lower (0.31) in the migrants and relatively higher (0.39) in the residents. Different demographic outcomes resulting from environment, predation, movements and ecological factors including resource competition have conservation implications for the two sub‐populations.     

African Vultures Don’t Follow Migratory Herds: Scavenger Habitat Use Is Not Mediated by Prey Abundance

The ongoing global decline in vulture populations raises major conservation concerns, but little is known about the factors that mediate scavenger habitat use, in particular the importance of abundance of live prey versus prey mortality. We test this using data from the Serengeti-Mara ecosystem in East Africa. The two hypotheses that prey abundance or prey mortality are the main drivers of vulture habitat use provide alternative predictions. If vultures select areas based only on prey abundance, we expect tracked vultures to remain close to herds of migratory wildebeest regardless of season. However, if vultures select areas where mortality rates are greatest then we expect vultures to select the driest regions, where animals are more likely to die of starvation, and to be attracted to migratory wildebeest only during the dry season when wildebeest mortality is greatest. We used data from GSM-GPS transmitters to assess the relationship between three vulture species and migratory wildebeest in the Mara-Serengeti ecosystem. Results indicate that vultures preferentially cluster around migratory herds only during the dry season, when herds experience their highest mortality. Additionally during the wet season, Ruppell’s and Lappet-faced vultures select relatively dry areas, based on Normalized Difference Vegetation Index, whereas White-backed vultures preferred wetter areas during the wet season. Differences in habitat use among species may mediate coexistence in this scavenger guild. In general, our results suggest that prey abundance is not the primary driver of avian scavenger habitat use. The apparent reliance of vultures on non-migratory ungulates during the wet season has important conservation implications for vultures in light of on-going declines in non-migratory ungulate species and use of poisons in unprotected areas.     

Selectivity in large generalist herbivores: feeding patterns of African ungulates in a semi-arid habitat

Feeding habits of free-ranging wildebeest and zebra were monitored in a semi-arid nature reserve, bordering the southwestern part of Kruger National Park, South Africa. The purpose of study was to distinguish and define the feeding niches of two roughage grazers that occur in similar habitat types. The monthly compositions of diets were evaluated by direct observations of feeding bouts over a period of two years when rainfall patterns were average and animal populations were stable. Other analyses evaluated the standing biomass of grass species in the reserve during the wet summer and dry winter seasons. A considerable overlap of grass species composition was found in the diets of wildebeest and zebra. Ordination of bi-monthly records of the diet composition showed greater variations in scores of grasses in zebra diet in comparison to wildebeest. Seasonal patterns were more apparent in the wildebeest diet. Preference ranking of grass species indicated that zebra diet remained constant in winter and summer. Wildebeest diet however, alternated with seasons, showing high preferences during the winter months for grass species which were rejected during summer. The combined assessment of results from three separate statistical methods analysing temporal patterns and preferences in diet composition revealed contradictory trends. The solution, however, relied on the initial assumptions posed. Hence, wildebeest and zebra are essentially generalist feeders which show a limited amount of preference in their choice of diet.     

Assessing introgressive hybridization between blue wildebeest (<Emphasis Type="Italic">Connochaetes taurinus</Emphasis>) and black wildebeest (<Emphasis Type="Italic">Connochaetes gnou</Emphasis>) from South Africa

Introgressive hybridization poses a threat to the genetic integrity of black wildebeest (Connochaetes gnou) and blue wildebeest (Connochaetes taurinus) populations in South Africa. Black wildebeest is endemic to South Africa and was driven to near extinction in the early 1900s due to habitat destruction, hunting pressure and disease outbreaks. Blue wildebeest on the other hand are widely distributed in southern and east Africa. In South Africa the natural distribution ranges of both species overlap, however, extensive translocation of black wildebeest outside of its normal distribution range in South Africa have led to potential hybridization between the two species. The molecular identification of pure and admixed populations is necessary to design viable and sustainable conservation strategies, since phenotypic evidence of hybridization is inconclusive after successive generations of backcrossing. The aim of this study was to assess levels of hybridization in wildebeest using both species-specific and cross-species microsatellite markers. Black wildebeest (157) and blue wildebeest (122) from provincial and national parks and private localities were included as reference material, with 180 putative hybrid animals also screened. A molecular marker panel consisting of 13 cross-species and 11 species-specific microsatellite markers was developed. We used a Bayesian clustering model to confirm the uniqueness of blue- and black wildebeest reference groups, assign individuals to each of the two clusters, and determine levels of admixture. Results indicated a clear partition between black wildebeest and blue wildebeest (the average proportions of membership to black wildebeest and blue wildebeest clusters were QI?=?0.994 and QI?=?0.955 respectively). From the putative hybrid samples, only five hybrid individuals were confirmed. However, high levels of linkage disequilibrium were observed in the putative hybrid populations which may indicate historical hybridization. Measures of genetic diversity in the black wildebeest populations were found to be lower than that of the blue wildebeest. The observed lower level of genetic diversity was expected due to the demographic history of the specie. This study will make a significant contribution to inform a national conservation strategy to conserve the genetic integrity of both species.     

Alteration in diel activity patterns as a thermoregulatory strategy in black wildebeest (<Emphasis Type="Italic">Connochaetes gnou</Emphasis>)

The nychthemeral activity patterns of a population of female black wildebeest inhabiting a shadeless environment were surveyed periodically over 1 year. The wildebeest fed mostly at night, with the proportion of feeding at night increasing when ambient conditions were hotter. Inactive periods were spent mostly lying during cooler weather but standing as days became hotter. We suggest that the entire suite of behavioural adjustments is beneficial to heat exchange with the environment. Behaviour patterns were markedly different during one warm weather survey, from the other warm weather surveys, when an 8-month dry spell had just been broken. We suggest that this may reflect the availability of water for autonomic thermoregulation, a consequent decreased reliance on behavioural thermoregulation, and a release of the thermal constraints on foraging. Our results help to explain the ability of black wildebeest to maintain body core temperature within a very narrow range despite being exposed to an environment with large nychthemeral variations in thermal conditions and offering little in the way of microclimate selection.     

Larger antelopes are sensitive to heat stress throughout all seasons but smaller antelopes only during summer in an African semi-arid environment

Heat stress can limit the activity time budget of ungulates due to hyperthermia, which is relevant for African antelopes in ecosystems where temperature routinely increases above 40 °C. Body size influences this thermal sensitivity as large bodied ungulates have a lower surface area to volume ratio than smaller ungulates, and therefore a reduced heat dissipation capacity. We tested whether the activity pattern during the day of three antelope species of different body size—eland, blue wildebeest and impala—is negatively correlated with the pattern of black globe temperature (BGT) during the day of the ten hottest days and each season in a South African semi-arid ecosystem. Furthermore, we tested whether the larger bodied eland and wildebeest are less active than the smaller impala during the hottest days and seasons. Our results show that indeed BGT was negatively correlated with the diurnal activity of eland, wildebeest and impala, particularly during summer. During spring, only the activity of the larger bodied eland and wildebeest was negatively influenced by BGT, but not for the smallest of the three species, the impala. We argue that spring, with its high heat stress, coupled with poor forage and water availability, could be critical for survival of these large African antelopes. Our study contributes to understanding how endothermic animals can cope with extreme climatic conditions, which are expected to occur more frequently due to climate change.     

Habitat use by black bears in relation to conspecifics and competitors

Sympatric black bears (Ursus americanus) and brown bears (Ursus arctos) are common in many boreal systems; however, few predator assemblages are known to coexist on a single seasonally abundant large prey item. In lowland southwestern interior Alaska, black bears and brown bears are considered the primary cause of moose (Alces alces) calf mortality during the first 6 weeks of life. The objective of this study was to document habitat use of global-positioning system (GPS)-collared black bears during peak and non-peak seasons of black bear-induced and brown bear-induced moose calf mortality within southwestern interior Alaska, in spring 2002. We compared habitats of GPS-collared black bears to those of presumably uncollared black bears and brown bears at their moose calf mortality sites. Results from this study suggest that GPS-collared black bears use similar habitat as conspecifics more than expected during the peak period of black bear predation on moose calves, whereas they use habitat in proportion to home range availability during the peak in brown bear predation on moose calves. Sex-specific Ivlev's electivity indices describe greater than expected use of mixed-deciduous forest and needleleaf forest by male GPS-collared black bears during the peak of moose calf predation, whereas females have a tendency to use these habitats less than expected. Juvenile GPS-collared black bears largely use the same habitat as other sympatric predators during the peak of moose calf predation, whereas during the non-peak period juveniles use opposite habitats as adult GPS-collared black bears. The outcome of this study offers possible explanations (e.g., sex, age) for spatial overlap or segregation in one member of a complex predator guild in relation to a seasonal pulse of preferred prey.     

The pattern of lion predation in Nairobi Park

The feeding habits of lions in Nairobi National Park have been observed between 1968 and 1972. Nairobi Park is briefly described and the herbivore and predator populations are discussed. The relationship between the changing status of the prey population for the period 1968-72 and the feeding habits of the lions is examined and compared with data from earlier years. Selection ratio (preference ratio) for three of the most important prey species is more closely adjusted to the abundance of these species in the total ungulate population than was the case prior to 1968. Only warthog and eland form an exception. Predation on wildebeest shows the most marked decrease although this species has been increasing during the last 5 years. Wildebeest, kongoni, zebra and warthog have provided 80% of total kills throughout the study on the basis of numbers killed. On this basis, warthog has the highest preference rating. However, the largest contribution to the lions' diet expressed in kg is by kongoni, followed by zebra, wildebeest, eland and warthog, in that order. Kongoni and wildebeest contribute most during the first half of the year and zebra and eland during the last 6 months. Selection for males is significant in zebra and eland and highly significant in kongoni, whilst only in zebra is selection for juveniles evident.     

Predicted impact of barriers to migration on the Serengeti wildebeest population

The Serengeti wildebeest migration is a rare and spectacular example of a once-common biological phenomenon. A proposed road project threatens to bisect the Serengeti ecosystem and its integrity. The precautionary principle dictates that we consider the possible consequences of a road completely disrupting the migration. We used an existing spatially-explicit simulation model of wildebeest movement and population dynamics to explore how placing a barrier to migration across the proposed route (thus creating two disjoint but mobile subpopulations) might affect the long-term size of the wildebeest population. Our simulation results suggest that a barrier to migration--even without causing habitat loss--could cause the wildebeest population to decline by about a third. The driver of this decline is the effect of habitat fragmentation (even without habitat loss) on the ability of wildebeest to effectively track temporal shifts in high-quality forage resources across the landscape. Given the important role of the wildebeest migration for a number of key ecological processes, these findings have potentially important ramifications for ecosystem biodiversity, structure, and function in the Serengeti.     

Body temperature variation of South African antelopes in two climatically contrasting environments

To understand the adaptive capacity of a species in response to rapid habitat destruction and climate change, we investigated variation in body temperature (T_b) of three species of antelope, namely eland, blue wildebeest and impala, using abdominally-implanted temperature data loggers. The study was conducted at two climatically contrasting environments in South Africa, one with a less seasonal and mild winter (Mapungubwe National Park) and the other with a more seasonal, long and cold winter (Asante Sana Game Reserve). Since the habitat with long and cold winters would be suboptimal for these African antelopes, which evolved in less seasonal and hot environments, antelopes in Asante Sana were expected to exhibit a larger amplitude in T_b and a lower minimum body temperature (Min T_b) during winter to reduce T_b and the ambient temperature (T_b−T_a) gradient to save energy. In both eland and impala, 24-h body temperature amplitude did not differ between the study sites, regardless of season. Conversely, wildebeest in Mapungubwe showed a higher variability in the 24-h amplitude of body temperature and also a lower Min T_b during winter and spring than the wildebeest in Asante Sana. This variation in T_b among Mapungubwe wildebeest was influenced by both the amplitude of ambient temperature (positive) and cumulative rainfall (negative), which was not the case for wildebeest in Asante Sana. We propose that the low Min T_b of wildebeest in Mapungubwe was the result of nutritional stress during winter and spring; an evident response even during a year of average rainfall. Therefore, these wildebeest apparently live in a physiologically stressful environment. With the predicted increase in the frequency and intensity of drought periods in southern Africa, wildebeest and other grazers, will likely experience greater nutritional stress in the future.     

Experimental infection of wildebeest with the herpesvirus of infectious bovine rhinotracheitis/infectious pustular vulvovaginitis.

Intravaginal inoculation of a wildebeest (Connochaetes taurinus) with a wildebeest strain of the infectious bovine rhinotracheitis/infectious pustular vulvovaginitis herpesvirus induced only mild vulvovaginitis. The same virus did not produce any disease in another wildebeest exposed intranasally. A wildebeest bull which was inoculated by preputial instillation developed mild posthitis. The virus was reisolated only from the sites of inoculation. A carrier state was initiated in a wildebeest inoculated only once, intravaginally. The presence of this virus in the various secretions is a potential source for venereal transmission.     

Observations on the epidemiology of the herpesvirus of infectous bovine rhinotracheitis/infectious pustular vulvovaginitis in wildebeest.

Spontaneous vulvovaginitis erupted in wildebeest (Connochaetes taurinus) after betamethasone inoculation. Infectious bovine rhinotracheitis/infectious pustular vulvovaginitis (IBR/IPV) is probably a venereal disease because virgin wildebeest did not develop vulvovaginitis after betamethasone injections, nor was the virus transmitted to these virgin wildebeest and steers which were in pen contact with the affected animals. A domestic bovine heifer developed mild IPV and became a virus carrier, when exposed to the wildebeest IPV virus by vaginal instillation.     

Trophic ecology of two savanna grazers,blue wildebeest <Emphasis Type="Italic">Connochaetes taurinus</Emphasis> and black wildebeest <Emphasis Type="Italic">Connochaetes gnou</Emphasis>

The feeding niches and trophic ecology of two South African grazers, blue wildebeest Connochaetes taurinus and black wildebeest Connochaetes gnou, are compared using stable carbon and nitrogen isotope data from feces and tooth dentine collagen. As sympatric, closely related taxa predicted to occupy similar trophic positions, the blue and black wildebeest provide a good model for studying the mechanisms of coexistence and macroevolution in mammals. Data from feces collected from a single reserve in the Free State Province reveal different trophic behaviors between two herds of blue wildebeest and between both compared with a single herd of black wildebeest. These data suggest that sympatric coexistence of blue and black wildebeest is facilitated by differential niche occupation at family group or herd levels, rather than between species. However, such separation does not occur over longer time scales: results from dentine collagen support the hypothesis that the two species are indistinct in terms of trophic behavior, although blue wildebeest show more feeding flexibility, probably because of their wider habitat tolerance range. Similarities in premaxillary width of males and females of both species also suggest that both species are adapted to similar feeding styles. Thus, it is unlikely that changes in trophic behavior provided the trigger for divergence of the black from the blue wildebeest lineage in the Middle Pleistocene. We argue that the case of these two species represents an example of speciation that was not driven by resource competition, as is often assumed for many turnover events in mammalian evolution. We briefly discuss a previous suggestion that links black wildebeest evolution to their more territorial breeding behavior associated with Middle-to-Late Pleistocene landscape changes in southern Africa.     

The Economic Impact of Malignant Catarrhal Fever on Pastoralist Livelihoods

This study is the first to partially quantify the potential economic benefits that a vaccine, effective at protecting cattle against malignant catarrhal fever (MCF), could accrue to pastoralists living in East Africa. The benefits would result from the removal of household resource and management costs that are traditionally incurred avoiding the disease. MCF, a fatal disease of cattle caused by a virus transmitted from wildebeest calves, has plagued Maasai communities in East Africa for generations. The threat of the disease forces the Maasai to move cattle to less productive grazing areas to avoid wildebeest during calving season when forage quality is critical. To assess the management and resource costs associated with moving, we used household survey data. To estimate the costs associated with changes in livestock body condition that result from being herded away from wildebeest calving grounds, we exploited an ongoing MCF vaccine field trial and we used a hedonic price regression, a statistical model that allows estimation of the marginal contribution of a good’s attributes to its market price. We found that 90 percent of households move, on average, 82 percent of all cattle away from home to avoid MCF. In doing so, a herd’s productive contributions to the household was reduced, with 64 percent of milk being unavailable for sale or consumption by the family members remaining at the boma (the children, women, and the elderly). In contrast cattle that remained on the wildebeest calving grounds during the calving season (and survived MCF) remained fully productive to the family and gained body condition compared to cattle that moved away. This gain was, however, short-lived. We estimated the market value of these condition gains and losses using hedonic regression. The value of a vaccine for MCF is the removal of the costs incurred in avoiding the disease.     

Water provision alters wildebeest adaptive habitat selection and resilience in the Central Kalahari

Wildlife populations in semi‐arid regions require unrestricted mobility along ecological gradients and across large landscapes to enable adaptive responses to seasonal variability and patchy resources. In the Kalahari region of Botswana, herbivore populations historically depended on seasonal access to the nutrient‐rich Schwelle area in the wet season and to water from the Boteti River during drought periods. Blue wildebeest Connochaetes taurinus in the Central Kalahari Game Reserve (CKGR) have lost access to these key habitats due to fences and encroachment of livestock and humans. We deployed satellite collars onto 10 female wildebeest in the CKGR to examine seasonal movements and habitat selection in relation to the environmental conditions and fragmented ecosystem. Wildebeest favoured open, short‐grass pan habitats in all seasons, probably in response to better forage quality and lower predation risk. The ability to remain in pan habitats during the dry season was a result of artificial water provision. A wildebeest herd that had no artificial water in its home range survived the dry season, whereas those wildebeest that were accustomed to water provision died when their water points failed in the dry season. Thus, water provision altered adaptive behaviour and reduced resilience of the population to the arid environment.     

Grass greenness and grass height promote the resource partitioning among reintroduced Burchell's zebra and blue wildebeest in southern Mozambique

Differences in the selection of habitat and specific dietary items support resource partitioning and coexistence of sympatric African grazing herbivores, such as zebra and wildebeest. In Maputo Special Reserve (MSR), southern Mozambique, these two species were extirpated during the civil war (1977–1992); since 2010, they have been reintroduced into the Reserve. Identifying the resource selection by reintroduced species and how these species coexist, while utilising the same resources, is both of ecological interest and important for the management of wildlife communities and parks. This is a key application of our research. Therefore, the present study investigated resource partitioning between Burchell's zebra (Equus burchelli, Smuts 1832) and blue wildebeest (Connochaetes taurinus, Burchell 1823) in the MSR. We conducted the study from July 2016 to June 2017. The data were collected by direct observation, driving the vehicle along the reserve's roads that covered the vegetation communities where zebras and wildebeest are known to commonly occur. The composition of the diet and specific features of the grass grazed by the two species, including greenness, height, and the number of stems, were assessed. The widely available grass, Aristida barbicollis, contributed most to the diet of both herbivores. The dietary overlap between the two herbivores was higher during the dry season (95%) than wet season (86%). Resources partitioning appears to be determined, principally, by the height and greenness of the grass, with the zebra grazing taller grass, which may facilitate the access of the wildebeest to the greener, lower proportion of the forage. That results follow the expectation that, among native herbivores, overlap in resource use is not expected based on evolutionary segregation.     

Large herbivore conservation in a changing world: Surface water provision and adaptability allow wildebeest to persist after collapse of long‐range movements

Large herbivores, particularly wide‐ranging species, are extensively impacted by land use transformation and other anthropogenic barriers to movement. The adaptability of a species is, therefore, crucial to determining whether populations can persist in ever smaller subsets of their historical home ranges. Access to water, by drinking or from forage moisture, is an essential requirement, and surface water provision is thus a long‐established, although controversial, conservation practice. In the arid Kgalagadi Transfrontier Park (KTP), South Africa, surface water provision in the 1930s facilitated the establishment of a sedentary wildebeest (Connochaetes taurinus) population in a region historically accessed only in the wet season, via now collapsed long‐distance movements. Here, we investigate the behaviour and diet of this wildebeest population, and how these relate to water in the landscape, to better understand the process of transitioning from a mobile to sedentary population. Data from 26 monthly surveys reveal that wildebeest distributions are shaped by water availability and salinity, shade, forage, season and possibly predator detectability. Areas with saline or no water are used predominantly in the wet season when forage moisture is high. Wet season movements beyond the study area mean the timing of wildebeest grazing in these regions matches historical timing. Grass utilization field data suggest that the KTP grazer population experiences forage deficits during the dry season, when ~80% of grass tufts are grazed and C:N and crude protein levels decline. Nonetheless, dung isotope data show that wildebeest meet their crude protein intake requirements during the dry season, likely by consuming unprecedentedly high levels of browse (>33%). While restoring the full historical range and movements of most large herbivore populations is not possible, these findings highlight that understanding the behavioural and dietary adaptability of a species can augment ‘next best’ efforts to conserve viable populations while home ranges contract.