Human-hippo conflicts around Lake Tana Biosphere Reserve, Ethiopia: Vulnerability of hippopotamus in human-dominated landscape.

Currently, the demand of the human population for more land, water, and other natural resources from wildlife habitats is increasing all over the world. Such intense human pressure results in conflict with wildlife and the impacts affect both parties negatively. The human-hippo conflict poses a serious problem for both local farmers' livelihoods and hippo conservation. To date, the extent of human-hippo conflict is poorly documented in Ethiopia. Specifically, the extent of human-hippo conflicts around Lake Tana Biosphere Reserve (LTBR) is unknown. Therefore, this study aimed to investigate the extent of human-hippo conflict, and possible mitigation measures proposed by the local people around LTBR, Ethiopia. We conducted a questionnaire interview with the household head, the household head's wife, or other adults ≥ 18 years old. All respondents reported that crop damage was the main cause of human-hippo conflict around LTBR. Livestock grazing competition (17.4%) and human attack (19.5%) were also sources of conflicts in the region. Respondents claimed that hippos destroyed crops including maize (Zea mays), teff (Eragrostis teff), finger millet (Eleusine coracana), and rice (Oryza sativa). Most (91.2%) respondents claimed that the severity of crop damage caused by hippos was high in the region. Most respondents (range 90 to 93%) complained about high crop damage suggesting that hippos be eliminated from the region. Local people estimated that the population sizes of hippos comprise an average of 243 individuals; however, we counted 122 hippos during our boat survey in the area. The result of this study showed that human-hippo conflicts cause negative effects on both farmers' livelihood and hippo conservation in the region. To mitigate human-hippo conflict, we suggest that proper land use zonation systems around key areas, broad awareness creation among local people, and alternative crop production should be promoted around the LTBR.

Feeding ecology of a highland population of hamadryas baboons (Papio hamadryas) at Borena-Sayint National Park, northern Ethiopia.

Studying the diet and feeding behavior of primates is essential to understanding their ecology and designing effective conservation plans. Despite decades of study on the hamadryas baboon (Papio hamadryas) in lowland habitats, little is known about the feeding ecology of this species in highland ecosystems. To address this empirical gap, we tracked temporal changes in vegetation abundance and their relation to the dietary choices of hamadryas baboons in highland habitat at Borena-Sayint National Park (BSNP) in northern Ethiopia. We performed behavioral scan sampling on a focal study band of 21-37 hamadryas baboons over a 12-month period. We found that mature and young leaves were the most abundant plant parts throughout the year, while fruits and flowers were the least abundant, with significant seasonal variation that followed the bimodal pattern of rainfall characteristic of the Ethiopian highlands ecosystem. The annual diet of hamadryas baboons at BSNP consisted mostly of fruits (32.0%) and graminoid blades (21.2%), and included 52 food species across 22 families of plants and three families of animals. Food raided from nearby farms accounted for 8.8% of their diet. The availability of fruits and flowers was positively correlated with their consumption, suggesting that these are preferred foods, whereas graminoid blades, and other leaves, appeared to be less preferred foods. The feeding ecology of hamadryas baboons at BSNP differs considerably from that of lowland populations. The well-studied lowland hamadryas baboons in Awash National Park obtain much of their diet from Acacia species and palm fruit, whereas those at BSNP, where Acacia trees are rare and palms are absent, relied on Olinia rochetiana and Rosa abyssinica for a combined 27% of their annual diet. The reliance of hamadryas baboons at BSNP on cultivated crops for nearly one-tenth of their diet leads to conflict with humans and warrants more detailed study so that this issue can be addressed in conservation plans for the area.

Population size and habitat preference of the Omo River guereza (Colobus guereza guereza) in a multi-habitat matrix in the central highlands of Ethiopia.

Given the current rate of habitat degradation and loss in the tropics, data on primate population densities and habitat use are indispensable for assessing conservation status and designing feasible management plans for primates. The Omo River guereza (Colobus guereza guereza) is a subspecies of the eastern black-and-white colobus monkey endemic to the western Rift Valley forests of Ethiopia. Their restricted distribution along with habitat loss and hunting within their range render them vulnerable to local extirpation and extinction. Furthermore, there are no published data available on the population status and habitat use patterns of the Omo River guereza. We therefore aimed to assess the population size of Omo River guerezas in different habitats (Erica-Juniperus mixed forest, mixed plantation forest, undisturbed natural forest, disturbed natural forest) using transect surveys at Wof-Washa Natural State Forest (WWNSF) in central Ethiopia. Our surveys covered a cumulative distance of 88.5 km in four different habitats, during which we recorded a total of 140 Omo River guereza groups. The average group density was 14.3 groups/km2, average individual density was 94.4 individuals/km2, and we estimated the total population size within WWNSF to be 2549 individuals. The sex ratio of the population was split evenly between males and females, though the age classes skewed strongly towards adults. Of the habitats surveyed, the highest group encounter rate (1.83 groups/km) occurred in the disturbed natural forest. However, the highest individual density (110.1 individuals/km2) was recorded in undisturbed natural forest. Still, sizable densities (group and individual) were recorded in three of the disturbed habitats (disturbed natural forest, mixed plantation forest, and to a lesser extent Erica-Juniperus mixed forest). Our study offers the first baseline information with which to compare future population density estimates and habitat use in the range of Omo River guerezas.

Phylogeography, mitochondrial DNA diversity, and demographic history of geladas (Theropithecus gelada).

The large-bodied, terrestrial primates in the tribe Papionini are among the most intensely studied animals in the world, yet for some members of this tribe we know comparatively little about their evolutionary history and phylogeography. Geladas (Theropithecus gelada Rüppell, 1835), endemic primates of the Ethiopian highlands, are largely unstudied both in genetic diversity and intrageneric phylogeny. Currently, a northern and central subspecies and one isolated southern population are recognized, of which the central is classified as Least Concern, the northern as Vulnerable, and the southern is not yet assessed. The distribution and taxonomy of the subspecies remain poorly defined. Here, we estimate the mitochondrial DNA (mtDNA) diversity and phylogenetic relationships among gelada mtDNA lineages based on samples across the entire species range. We analysed 1.7 kb-long sequences of the mtDNA genome, spanning the cytochrome b gene and the hypervariable region I of the D-loop, derived from 162 faecal samples. We detected five major haplogroups or clades (south, central-1, central-2, north-1, north-2) which diverged between 0.67 and 0.43 million years ago, thus suggesting a rapid radiation, resulting in largely unresolved intrageneric phylogenetic relationships. Both, the northern and central demes contain two similarly valid haplogroups, each with little or no geographic segregation among respective haplogroups. Effective population sizes of the northern and central demes decreased during and after the last glacial maximum but remained stable for the southern deme, although on a very low level. The distribution of haplogroups within the geographic ranges of the putative gelada subspecies indicates that mtDNA sequence information does not allow reliable taxonomic inferences and thus is not sufficient for solving the taxonomic rank of the three demic populations, with the possible exception of the southern population. Nevertheless, due to the genetic differences all three populations deserve conservation efforts, in particular the smallest southern population.

Multilevel social structure and diet shape the gut microbiota of the gelada monkey, the only grazing primate.

BACKGROUND: The gelada monkey (Theropithecus gelada), endemic to the Ethiopian highlands, is the only graminivorous primate, i.e., it feeds mainly on grasses and sedges. In spite of known dental, manual, and locomotor adaptations, the intestinal anatomy of geladas is similar to that of other primates. We currently lack a clear understanding of the adaptations in digestive physiology necessary for this species to subsist on a graminoid-based diet, but digestion in other graminivores, such as ruminants, relies heavily on the microbial community residing in the gastrointestinal (GI) system. Furthermore, geladas form complex, multilevel societies, making them a suitable system for investigating links between sociality and the GI microbiota. RESULTS: Here, we explore the gastrointestinal microbiota of gelada monkeys inhabiting an intact ecosystem and document how factors like multilevel social structure and seasonal changes in diet shape the GI microbiota. We compare the gelada GI microbiota to those of other primate species, reporting a gradient from geladas to herbivorous specialist monkeys to dietary generalist monkeys and lastly humans, the ultimate ecological generalists. We also compare the microbiotas of the gelada GI tract and the sheep rumen, finding that geladas are highly enriched for cellulolytic bacteria associated with ruminant digestion, relative to other primates. CONCLUSIONS: This study represents the first analysis of the gelada GI microbiota, providing insights into the adaptations underlying graminivory in a primate. Our results also highlight the role of social organization in structuring the GI microbiota within a society of wild animals.

Ecological plasticity in the gastrointestinal microbiomes of Ethiopian Chlorocebus monkeys.

Human activities can cause habitat degradation that may alter the types and quality of available food resources and thus influence the microbiomes of wild animal populations. Furthermore, seasonal shifts in food availability may cause adaptive responses in the gut microbiome to meet the need for different metabolic capabilities. Here, we demonstrate local-scale population structure in the gastrointestinal microbiotas of Chlorocebus monkeys, in southern Ethiopia, in response to varying degrees of human encroachment. We further provide evidence of adaptation to ecological conditions associated with the dry and wet seasons, and show seasonal effects to be more pronounced in areas with limited human activity. Finally, we report species-level microbiota differences between the endemic Ethiopian Bale monkey, an ecological specialist, and generalist Chlorocebus species from the same geographical region.