Zebra Equus Quagga Research Articles

Using the multivariate Hawkes process to study interactions between multiple species from camera trap data.

Interspecific interactions can influence species' activity and movement patterns. In particular, species may avoid or attract each other through reactive responses in space and/or time. However, data and methods to study such reactive interactions have remained scarce and were generally limited to two interacting species. At this time, the deployment of camera traps opens new opportunities but adapted statistical techniques are still required to analyze interaction patterns with such data. We present the multivariate Hawkes process (MHP) and show how it can be used to analyze interactions between several species using camera trap data. Hawkes processes use flexible pairwise interaction functions, allowing us to consider asymmetries and variations over time when depicting reactive temporal interactions. After describing the theoretical foundations of the MHP, we outline how its framework can be used to study interspecific interactions with camera trap data. We design a simulation study to evaluate the performance of the MHP and of another existing method to infer interactions from camera trap-like data. We also use the MHP to infer reactive interactions from real camera trap data for five species from South African savannas (impala Aepyceros melampus, greater kudu Tragelaphus strepsiceros, lion Panthera leo, blue wildebeest Connochaetes taurinus and Burchell's zebra Equus quagga burchelli). The simulation study shows that the MHP can be used as a tool to benchmark other methods of interspecific interaction inference and that this model can reliably infer interactions when enough data are considered. The analysis of real data highlights evidence of predator avoidance by prey and herbivore-herbivore attraction. Lastly, we present the advantages and limits of the MHP and discuss how it can be improved to infer attraction/avoidance patterns more reliably. As camera traps are increasingly used, the multivariate Hawkes process provides a promising framework to decipher the complexity of interactions structuring ecological communities.

Ciliates from faeces of zebras Equus quagga from different zoos: species composition and intraspecies diversity

Ciliates from faeces of zebras Equus quagga from different zoos: species composition and intraspecies diversity

Resource pulses influence the spatio‐temporal dynamics of a large carnivore population

Resource availability is a key component in animal ecology, yet the manner in which carnivore populations respond to spatial and temporal fluctuations of resources remains unclear. We take a population‐level approach to determine how resource pulses, in this case a temporary hyper‐abundance of prey, influence the densities and space‐use of cheetahs Acinonyx jubatus. The Maasai Mara in Kenya experiences an annual migration of > 1.4 million wildebeest Connochaetes taurinus and large numbers of zebras Equus quagga and Thomson's gazelle Eudorcas thomsonii thereby providing a natural experiment to examine the influence of resource pulses on carnivore movement and densities. To draw inferences on fluctuating cheetah densities and space‐use, we collected unstructured search‐encounter data during eight sampling sessions, four during and four out of the migration, and analysed these using Bayesian spatially‐explicit capture–recapture (SECR) models with sex‐specific detection function parameters. Both densities and space‐use fluctuated seasonally but this varied according to sex. Local cheetah densities increased in areas and during times when prey abundance was highest but this was more pronounced for females than males. In terms of space‐use, movements were larger during the migration than out of the migration but this was more pronounced for males than females. These results suggest that males are influenced more by resource distribution whereas females by resource abundance. Overall densities did vary but there was no clear pattern in relation to resource pulses. Understanding the behavioural drivers of population dynamics in relation to resource pulses can provide important insights into ecological processes at multiple ecological levels.

Plains zebras bring evidence that dilution and detection effects may not always matter behaviorally and demographically

AbstractGroup living is assumed to benefit prey by reducing predation risk due to dilution and detection effects. This increased safety could be exchanged against a reduced individual vigilance leading to increased foraging and fitness until costs of intra‐group competition offset this benefit. However, very few studies have been able to directly test the relationship between individual fitness and group size in non‐cooperative breeding species. Therefore, evidence that dilution and detection effects do indeed translate into increased fitness under predation risk remains mostly theoretical. Here, we aimed at empirically testing whether group size influences beneficial and costly behaviors, and ultimately the survival of individuals, in a prey species facing heavy predation pressure. We focused on plains zebra Equus quagga of Hwange National Park in Zimbabwe, a high lion density area. We collected behavioral data (i.e., individual vigilance and foraging, collective vigilance, and agonistic interactions) that we used as proxies to investigate the costs and benefits of grouping in this species. We then fitted multistate capture‐mark‐recapture and Cox proportional‐hazards models to estimate apparent survival of adults and young zebras, respectively, and assess whether a demographic signal of group size could be found. Our results show that collective vigilance increases with group size, a prerequisite of the detection effect, but individual vigilance does not consistently decrease with group size, which suggests that there is no group size effect on individual vigilance. Agonistic interactions were rare. These results suggest that there are no foraging costs of grouping here, and even some benefits such as a better collective vigilance. However, any benefits of being in larger groups did not translate into increased survival, as we found no effect of group size on the apparent survival of individuals. Since dilution and detection effects do not matter behaviorally and demographically in these plains zebras living under high predation risk, these results challenge our understanding of how predation shapes animal sociality: fitness benefits of dilution or detection should not be assumed.

Zebra diel migrations reduce encounter risk with lions at night

Diel migrations (DM; back and forth diel movements along an ecological gradient) undertaken by prey to avoid predators during the day have been demonstrated in many taxa in aquatic ecosystems. In terrestrial ecosystems, prey often shift between various vegetation types whose cover determine their vulnerability (i.e., likelihood of being killed when attacked). We conceptualized that in terrestrial ecosystems, DM could also occur and that the contribution of DM and shifts in vegetation cover use in reducing predation risk should depend upon the predator behaviour and the correlation between encounter risk and vulnerability across vegetation types. We further hypothesized that when the predator distribution is predictable, terrestrial prey could have evolved DM strategies taking them away from the predator when it is active or efficient. We investigated whether plains zebras Equus quagga perform DM in Hwange National Park (Zimbabwe). There, zebras can forage in large patches of open grasslands located near waterholes where they can also easily detect predators. However, they are there at high risk of encountering their main predator, lions Panthera leo, especially at night. We found out that zebras employ a DM anti-predator strategy. Zebras forage near waterholes during the day but move away from them at sunset, when lions become active. We demonstrated that this DM, occurring over a few kilometres, dramatically reduces their night-time risk of encountering lions, which generally remain close to waterholes. Zebra changes in night-time selection for vegetation cover types reduced their risk of encountering lions much less. This may arise from a trade-off between encounter risk and vulnerability across vegetation types, with zebras favouring low vulnerability once DM has reduced encounter risk. In summary, here we (a) quantify, in a terrestrial system, the effect of a predator-induced DM on the likelihood of encountering a predator and (b) distinguish the effects of the DM on encounter risk from those related to day/night changes in selection for vegetation types. We discuss how prey partition their risk between encounter risk and habitat-driven vulnerability and why it is likely critical to understand the emergence of anti-predator behavioural strategies.

Revealing kleptoparasitic and predatory tendencies in an African mammal community using camera traps: a comparison of spatiotemporal approaches

Camera trap data are increasingly being used to characterise relationships between the spatiotemporal activity patterns of sympatric mammal species, often with a view to inferring inter‐specific interactions. In this context, we attempted to characterise the kleptoparasitic and predatory tendencies of spotted hyaenasCrocuta crocutaand lionsPanthera leofrom photographic data collected across 54 camera trap stations and two dry seasons in Tanzania's Ruaha National Park. We applied four different methods of quantifying spatiotemporal associations, including one strictly temporal approach (activity pattern overlap), one strictly spatial approach (co‐occupancy modelling), and two spatiotemporal approaches (co‐detection modelling and temporal spacing at shared camera trap sites). We expected a kleptoparasitic relationship between spotted hyaenas and lions to result in a positive spatiotemporal association, and further hypothesised that the association between lions and their favourite prey in Ruaha, the giraffeGiraffa camelopardalisand the zebraEquus quagga, would be stronger than those observed with non‐preferred prey species (the impalaAepyceros melampusand the dikdikMadoqua kirkii). Only approaches incorporating both the temporal and spatial components of camera trap data resulted in significant associative patterns. The latter were particularly sensitive to the temporal resolution chosen to define species detections (i.e. occasion length), and only revealed a significant positive association between lion and spotted hyaena detections, as well as a tendency for both species to follow each other at camera trap sites, during the dry season of 2013, but not that of 2014. In both seasons, observed spatiotemporal associations between lions and each of the four herbivore species considered provided no convincing or consistent indications of any predatory preferences. Our study suggests that, when making inferences on inter‐specific interactions from camera trap data, due regards should be given to the potential behavioural and methodological processes underlying observed spatiotemporal patterns.

Interspecific interference competition at the resource patch scale: do large herbivores spatially avoid elephants while accessing water?

Animals may anticipate and try to avoid, at some costs, physical encounters with other competitors. This may ultimately impact their foraging distribution and intake rates. Such cryptic interference competition is difficult to measure in the field, and extremely little is known at the interspecific level. We tested the hypothesis that smaller species avoid larger ones because of potential costs of interference competition and hence expected them to segregate from larger competitors at the scale of a resource patch. We assessed fine-scale spatial segregation patterns between three African herbivore species (zebra Equus quagga, kudu Tragelaphus strepsiceros and giraffe Giraffa camelopardalis) and a megaherbivore, the African elephant Loxodonta africana, at the scale of water resource patches in the semi-arid ecosystem of Hwange National Park, Zimbabwe. Nine waterholes were monitored every two weeks during the dry season of a drought year, and observational scans of the spatial distribution of all herbivores were performed every 15min. We developed a methodological approach to analyse such fine-scale spatial data. Elephants increasingly used waterholes as the dry season progressed, as did the probability of co-occurrence and agonistic interaction with elephants for the three study species. All three species segregated from elephants at the beginning of the dry season, suggesting a spatial avoidance of elephants and the existence of costs of being close to them. However, contrarily to our expectations, herbivores did not segregate from elephants the rest of the dry season but tended to increasingly aggregate with elephants as the dry season progressed. We discuss these surprising results and the existence of a trade-off between avoidance of interspecific interference competition and other potential factors such as access to quality water, which may have relative associated costs that change with the time of the year.

Lion proximity, not moon phase, affects the nocturnal movement behaviour of zebra and wildebeest

AbstractMoon phase affects nocturnal activity patterns in mammals. Among ungulates, a number of studies have found animals to be more active over full moon nights. This may be because increased luminosity provides increased opportunity to forage and/or increased ability to detect predators; known as the visual acuity hypothesis. Here, we use GPS‐derived movement data to test for the influence of moon phase on plains zebra Equus quagga and blue wildebeest Connochaetes taurinus activity in Kruger National Park, South Africa. We compare animal movement (rate and displacement) over full and new moon nights, and consider the effect of lion proximity. We found that lion proximity largely determined the nocturnal movements of zebra and wildebeest, not moon phase. When lions were >1 km away, there was no difference in the nocturnal movement activity of prey animals over full and new moon conditions, contradicting previous findings. When lions were within 1 km of these animals, however, the movement of zebra and wildebeest greatly increased over the new moon, the relatively dark period when lion were most likely hunting. Although we could not explicitly test for predator detection here, our findings suggest that the visual acuity hypothesis does not hold for zebra and wildebeest in Kruger National Park (KNP) given that there is no evidence for increased foraging activity over the full moon. The influence of moon phase on the nocturnal activity of African ungulates may be more complicated than anticipated, and we suggest that this cannot be estimated unless predator proximity is accounted for.

Ungulate distributions in a rangeland with competitors, predators and pastoralists

Summary African rangelands support diverse ungulate communities whose member species exhibit unique combinations of body morphology and behaviour that have evolved over millions of years to limit the effects of competition and predation on fitness, and more recently, to cope with people and livestock. The mechanisms by which native ungulates cope with the combined effects of competition, predation and human disturbance are poorly understood. Addressing this knowledge gap will help guide management and conservation plans for large mammal communities outside of strictly protected areas. We conducted animal counts on line transects and used a spatially explicit distance sampling model to test the influence of bottom–up effects (vegetation), top–down effects from African lion Panthera leo and spotted hyena Crocuta crocuta and human disturbance (livestock density, occupied human settlements) on native ungulate densities and distributions across a multiple‐use rangeland in Kenya. We examined five species that varied in body morphology and foraging strategy, including two large‐bodied grazers (zebra Equus quagga; wildebeest Connochaetes taurinus), two medium‐bodied, mixed‐feeders (Grant's gazelle Nanger granti; impala Aepyceros melampus) and one very large‐bodied browser (giraffe Giraffa camelopardalis tippelskirchi). Densities and distributions of all species varied across available land‐use types, with bottom–up effects (vegetation) and human disturbance having the strongest overall effects. Responses varied by ungulate foraging strategy. Distributions of grazers and the browser (giraffe) changed seasonally, while distributions of mixed‐feeders and a grazer (zebra) changed diurnally. At broad spatial scales, ungulates did not respond to long‐term variation in predation risk though they have been shown to respond behaviourally to short‐term variation in risk. Synthesis and applications. Our results revealed that native ungulates in this multiple‐use rangeland occur at densities comparable to many flagship protected area populations. We attribute observed densities to spatial heterogeneity across this landscape that included variation in human land use (community conservation area, seasonal settlements and livestock grazing, permanent settlements) and vegetation (grassland, bushland, woodland) that changed through time (seasonally, diurnally). This variation allowed ungulates to carve out ecological niches while reducing exposure to the potential limiting effects of competition and human disturbance. For some species, securing access to forage resources and avoiding human disturbance may be associated with costs through increased risk of predation. Our research reveals the trade‐offs native ungulates make to cope with changes in forage availability, human disturbance and predation risk, providing important insights to help guide native ungulate conservation efforts in multiple‐use rangelands.

Three legs good, four legs better: Making a quagga whole again with 3D printing

Abstract Specimens of extinct animals are among the most precious items in a museum’s collection. They are vital for research and education, especially those that have become extinct relatively recently due to human activity. Only seven skeletons of the extinct subspecies of plains zebra Equus quagga quagga are known to exist in museum collections worldwide, including a specimen on display at the Grant Museum of Zoology, London. However, the left hind leg and right scapula of this specimen have been missing for many years. As part of a recent project to conserve and remount this skeleton, the left scapula and articulated right hind limb were scanned using computed tomography (CT) so that mirrored data could be used to 3D print the missing bones. The 3D-printed models installed on the original specimen do more than provide an anatomically complete skeleton and improve the physical stability of the specimen; the black 3D printed bones contrast with the rest of the skeleton, which highlights the work undertaken and provides a more engaging exhibit. The CT scans are also available for research and as an interactive 3D model within the display.

Reactive responses of zebras to lion encounters shape their predator–prey space game at large scale

The predator–prey space game and the costs associated with risk effects are affected by prey 1) proactive adjustments (when prey modify their behaviour in response to an a priori assessment of the risk level) and 2) reactive adjustments (when prey have detected an immediate threat). Proactive adjustments are generally well‐studied, whereas the frequency, strength and duration of reactive adjustments remain largely unknown. We studied the space use and habitat selection of GPS‐collared zebrasEquus quaggafrom 2 to 48 h after an encounter with lionsPanthera leo. Lion–zebra encounters generally occurred close to artificial waterholes (< 1 km). Two hours after an encounter, zebras were more likely to have fled than stay when the encounter occurred in more risky bushy areas. During their flight, zebras selected grasslands more than usual, getting great visibility. Regardless of their initial response, zebras finally fled at the end of the night and reached areas located far from waterholes where encounters with lions are less frequent. The large‐scale flights (∼4–5 km) of zebras led to a local zebra depression for lions. Zebras that had fled immediately after the encounter resumed their behaviour of coming close to waterholes on the following day. However, zebras that had initially stayed remained far from waterholes for an extra 24 h, remaining an elusive prey for longer. The delay in the flight decision had different short‐term consequences on the lion–zebra game. We reveal that the spatial context of the encounter shapes the immediate response of prey, and that encountering predators induces strong behavioural responses: prey flee towards distant, safer, areas and have a constrained use of key resource areas which are at the heart of the predator–prey game at larger spatio‐temporal scales. Nighttime encounters were infrequent (once every 35 days on average), zebra responses were short‐lived (< 36 h) but occurred over a large spatial scale (several km).

Population genetic diversity and hybrid detection in captive zebras.

Zebras are members of the horse family. There are three species of zebras: the plains zebra Equus quagga, the Grevy’s zebra E. grevyi and the mountain zebra E. zebra. The Grevy’s zebra and the mountain zebra are endangered, and hybridization between the Grevy’s zebra and the plains zebra has been documented, leading to a requirement for conservation genetic management within and between the species. We characterized 28 microsatellite markers in Grevy’s zebra and assessed cross-amplification in plains zebra and two of its subspecies, as well as mountain zebra. A range of standard indices were employed to examine population genetic diversity and hybrid populations between Grevy’s and plains zebra were simulated to investigate subspecies and hybrid detection. Microsatellite marker polymorphism was conserved across species with sufficient variation to enable individual identification in all populations. Comparative diversity estimates indicated greater genetic variation in plains zebra and its subspecies than Grevy’s zebra, despite potential ascertainment bias. Species and subspecies differentiation were clearly demonstrated and F1 and F2 hybrids were correctly identified. These findings provide insights into captive population genetic diversity in zebras and support the use of these markers for identifying hybrids, including the known hybrid issue in the endangered Grevy’s zebra.

A newly discovered wildlife migration in Namibia and Botswana is the longest in Africa

AbstractMigrations of most animal taxa are declining as a result of anthropogenic pressures and land-use transformation. Here, we document and characterize a previously unknown multi-country migration of Burchell's zebraEquus quaggathat is the longest of all recorded large mammal migrations in Africa. Our data from eight adult female zebras collared on the border of Namibia and Botswana show that in December 2012 all individuals crossed the Chobe River and moved due south to Nxai Pan National Park in Botswana, where they spent a mean duration of 10 weeks before returning, less directly, to their dry season floodplain habitat. The same southward movements were also observed in December 2013. Nxai Pan appeared to have similar environmental conditions to several possible alternative wet season destinations that were closer to the dry season habitat on the Chobe River, and water availability, but not habitat or vegetation biomass, was associated with higher-use areas along the migratory pathway. These results suggest a genetic and/or cultural basis for the choice of migration destination, rather than an environmental one. Regardless of the cause, the round-trip, straight-line migration distance of 500 km is greater than that covered by wildebeestConnochaetes taurinusduring their well-known seasonal journey in the Serengeti ecosystem. It merits conservation attention, given the decline of large-scale ecological processes such as animal migrations.

Are relatively rare antelope narrowly selective feeders? A sable antelope and zebra comparison

AbstractAnimals that are relatively rare in local species assemblages are commonly assumed to be narrowly selective in their habitat or dietary requirements, with the latter generally assessed in terms of the range of food types consumed. We investigated whether a narrow dietary range might help explain the restricted distribution and low local densities attained by sable antelope Hippotragus niger compared with other grazing ungulates. Selection by sable antelope for grass species, its relation to species availability and the resulting evenness of the diet were compared with these measures for zebra Equus quagga, which are assumed to be generalist feeders owing to their hindgut fermentation system, under dry season conditions when food was most limiting. Both grazers exhibited a clear distinction between highly favoured and infrequently accepted or rejected grass species in the same region, and both favoured mostly the same common grass species, but sable showed greater acceptance of several less common grass species than did zebra. Distinctions were evident among individual sable herds in favoured grass species, dependent on local availability. Dietary evenness was similar for sable and zebra herds overall, although seasonal trends differed depending on whether animals concentrated their diet more narrowly on a few grass species or broadened it during more extremely dry conditions. Hence, although sable were more narrowly selective for green leaf content than zebra, the dietary acceptance range of these two grazers at grass species level did not differ fundamentally. In particular, sable readily consumed tall grass species rated as having low to moderate forage value. This dietary tolerance enables sable antelope to occupy savannah woodlands associated with relatively infertile soils where the risk of predation is reduced due to the relatively low abundance of other prey. Accordingly, the causes of local rarity may lie in the restricted availability of food in the places to which these species are restricted by other factors.

Edge effects and large mammal distributions in a national park

AbstractWhile protected areas are a centrepiece of conservation, populations of animals in protected areas can still be subject to considerable human influence. Conservation theory suggests that many species should live at lower densities at the periphery of protected areas compared with the core area. Similarly, but more specifically, species subject to exploitation are expected to have lower densities in areas close to human settlements compared with more remote areas. Drawing upon distributional data of eight large African herbivore species (buffalo Syncerus caffer, elephant Loxodonta africana, giraffe Giraffa camelopardalis, impala Aepyceros melampus, topi Damaliscus lunatus, warthog Phacochoerus africanus, waterbuck Kobus ellipsiprymnus and zebra Equus quagga) sampled using ground surveys in 1995 and 1996, and seven large herbivore species (the same species without impala) sampled using aerial surveys from 1987 to 2009, we fitted logistic regression models and used an information theoretic model selection approach to test these two hypotheses in an East African savannah national park subject to illegal hunting from outside. In the vast majority of herbivore species, occupancy was not substantially affected by being close to the edge of the park or in close proximity to human villages. Furthermore, population declines witnessed in this protected area were not reflected in reduced occupancy near park boundaries. We conclude that assumed distributional differences between peripheral and core parts of reserves are not necessarily supported by empirical evidence, and that population declines within reserves do not inevitably proceed from boundaries inwards.

Effect of social system on allosuckling and adoption in zebras

AbstractAlthough nursing non‐filial offspring (allonursing) represents costly behaviour to the female, it occurs in a variety of taxa, including ungulates. The only three currently existing species of zebra differ in their ecology and social system. In the wild, mountain zebra Equus zebra and Grevy's zebra Equus grevyi live in arid environments, while plains zebra Equus quagga inhabit savannahs. Mountain and plains zebra mares form long‐term stable herds associated with a social hierarchy, whereas Grevy's zebra mares form loose associations of short duration. In this study, we investigated the occurrence of allosuckling in three zebra species at the Dvůr Králové Zoo, Czech Republic, during 1626 h of observation. We recorded no successful allosuckling bouts and only 1 and 22 attempts to allosuckle by foals of mountain and plains zebra, respectively, whereas we observed 117 attempts and 13 successful allosuckling bouts by Grevy's zebra foals. Moreover, more than half of all observed Grevy's zebra foals succeeded in allosuckling at least once. When rejecting an allosuckling attempt, Grevy's zebra mares were less aggressive than mountain and plains zebra mares. When a Grevy's zebra mare allowed occasional allosuckling by a non‐filial foal, the probability of long‐term allosuckling was smaller than that in mountain and plains zebra. We also present the first evidence of adoption in Grevy's zebra. We suggest that higher tolerance towards non‐filial offspring, including the occurrence of allosuckling in Grevy's zebra, was affected by the different social systems of zebra species.

Inter-birth interval in zebras is longer following the birth of male foals than after female foals

Mammalian reproductive rates vary among individuals for physiological and environmental reasons. This study aims to determine reproductive rates from an individually monitored population of wild Plains zebras Equus quagga, and to assess the sources of variability in inter-birth intervals. The animals were monitored, where possible, every six months from 2004 to 2011. Thirty nine intervals corresponding to 65 births in 26 mares were identified, using direct observations and faecal steroid monitoring. Mean foaling rate of the population is 0.74 foal/year, and comparable with the literature. There was no significant effect of mother’s age, nor of the season of previous birth on the length of inter-birth intervals. Inter-birth interval was significantly longer when the first foal was a male. This finding indicates that additional costs of having a son may delay future reproduction and thus reduce the total number of offspring a mare can have during her lifetime. Individually-based data provide critical information on the determinants of reproductive rates, and are therefore a key to understanding the causes of variations in life-history traits.

The costs of drinking: comparative water dependency of sable antelope and zebra

AbstractResource partitioning among the ungulate species occupying African savanna ecosystems has been well documented in relation to food resources and habitat features, but few studies have addressed how distinctions in surface water dependency contribute to coexistence. During the dry season surface water becomes restricted to a few perennial sources, while the food resources remaining at this time are also most limited in quantity, especially near water where animals congregate to drink. We compared the movement patterns to and from water of sable antelope Hippotragus niger and zebra Equus quagga herds in Kruger National Park (KNP), South Africa. Owing to distinctions in their digestive systems, we expected sable to drink less frequently than zebra, allowing sable to occupy regions further from surface water than zebra. Sable travelled to water at 2–4‐day intervals, versus 1–2‐day intervals for zebra. However, sable travelled c. 25% greater distances to water due to the location of their late dry season home ranges relative to perennial water sources; zebra home ranges were generally closer to water sources. Travelling 10–15 km to and from water substantially reduced time spent foraging and resting by both species on days when animals drank. Longer intervals between travel to water by the sable antelope herd enabled it to occupy regions of the landscape further from water than those heavily exploited by the more common grazers during the critical dry season months. By avoiding concentrations of other grazers, the sable also probably gained a reduction in predation risk, balancing the substantial costs in terms of time and energy associated with travel to water. Thereby the distinctions in water dependency of this relatively rare grazer facilitated its coexistence alongside more abundant grazers in the KNP.

Pattern of faecal 20-oxopregnane and oestrogen concentrations during pregnancy in wild plains zebra mares

Regulative endocrine mechanisms influence the reproductive behaviour and success of mammals, but they have been studied predominantly in domestic and captive animals. The study aims at describing the pattern of faecal 20-oxopregnane and oestrogen concentrations during pregnancy in wild plains zebra Equus quagga chapmani. Data were collected during wet and dry seasons 2007–2009. Enzyme Immunoassays were used to determine 20-oxopregnane and oestrogen concentrations in faecal samples (n=74) collected from individual mares (n=32) whose dates of foaling were known through long-term monitoring. Hormonal profiles were described with a General Additive Model (GAM: Hormone ∼ Days to Foaling). Faecal 20-oxopregnanes have a complex cycle during pregnancy (GAM, n=70, R2=0.616, p<0.001). From −250days to foaling, faecal 20-oxopregnane concentrations were above the baseline levels found in non-pregnant mares, peaking in the last 50days. Faecal oestrogen levels showed a clear peak in mid-pregnancy (GAM, n=62, R2=0.539, p<0.001). The sex of the foetus and season had no detectable effect on hormone concentrations during pregnancy. High levels (>200ng/g DW) of faecal 20-oxopregnanes associated with high (>160ng/g DW) faecal oestrogen levels indicate mid-pregnancy in c.90% of cases (16/17). High faecal 20-oxopregnanes (>200ng/g DW) and low faecal oestrogen levels (<160ng/g DW) indicate late pregnancy, again in c.90% of cases. Two faecal samples would allow the stage of pregnancy to be determined with confidence.

Influence of social upbringing on the activity pattern of captive lion Panthera leo cubs: Benefits of behavior enrichment

Abstract The influence of social upbringing on the activity pattern of lion Panthera leo cubs was investigated at three sites. In this study, stimulus objects such as sticks, grass, fresh dung (elephant Loxondota africana, zebra Equus quagga, impala Aepyceros melampus, duiker Sylvicapra grimmia, kudu Tragelaphus strepsiceros, giraffe Giraffa camelopardalis and wildebeest Connochaetes taurinus) and cardboard boxes, were utilized in an enrichment program aimed at encouraging active behaviors of captive lion cubs at Antelope Park and Masuwe. Lion cubs at Chipangali were not behaviorally enriched. Activity patterns were recorded for 10 days at each site. We recorded moving, resting, playing, grooming, visual exploration and display of hunting instincts. We found that behavioral enrichment enhanced the active behaviors of captive lion cubs. Orphan-raised cubs spent more time moving, playing and displaying hunting instincts than mother-raised cubs, but the time spent grooming was similar across areas and suggests that grooming is not influenced by enrichment. Mother-raised cubs spent more time engaged in visual exploration than orphan-raised cubs and this could be a behavior acquired from mothers or a result of confidence to explore because of their presence. Activity patterns were different among time treatments across our three study sites. Based on these findings, we suggest that lion cubs raised in captivity could benefit from behavioral enrichment to encourage active behaviors essential for eventual reintroduction into the wild.