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1.
Proc Natl Acad Sci U S A ; 119(50): e2206635119, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36490314

RESUMO

Ethiopia is home to one of the richest and most unique assemblages of fauna and flora on the African continent. Contained within its borders are two major centers of endemism, the mesic Roof of Africa (also known as the Ethiopian Highlands) and the arid Horn of Africa, resulting from the country's varied topography and consequent geographic isolation. These centers of endemism are crucial to global conservation as evidenced by their classification within the Eastern Afromontane and Horn of Africa biodiversity hotspots, respectively. Ethiopia's diverse ecosystems and the biodiversity they contain are increasingly threatened by climate change and the growing impacts of Africa's second largest human and largest livestock populations. In this paper, we focus on several key areas of recent and ongoing research on Ethiopian biodiversity that have broadened our understanding of nature and its conservation in Africa. Topics explored include the behavioral ecology of Ethiopia's large social mammals, the ecology and conservation of its unique coffee forests, and Ethiopian approaches to community conservation, fortress conservation, and nature-based solutions. We also highlight the increasing prominence of Ethiopian scientists in studies of the country's biodiversity in recent decades. We suggest promising avenues for future research in evolutionary biology, ecology, systematics, and conservation in Ethiopia and discuss how recent and ongoing work in Ethiopia is helping us better understand and conserve nature in the human-dominated landscapes of Africa and other tropical regions today.


Assuntos
Biodiversidade , Ecossistema , Humanos , Animais , Ecologia , Florestas , Mamíferos , Etiópia , Conservação dos Recursos Naturais
3.
BMC Ecol ; 20(1): 5, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992270

RESUMO

BACKGROUND: The availability of preferred habitats determines the spatial and temporal distribution of herbivores in savanna ecosystems. Understanding habitat preference of a targeted wildlife species is crucial for developing effective conservation strategies. Habitat preference of large grazers in connection to grass height and post-fire effect has been debated for the last century. Here, we examined the effects of season, grass height and burning on the habitat preference on Swayne's hartebeest (Alcelaphus buselaphus swaynei) in Maze National Park. Data for seasonal habitat selection were collected using both direct observation along established transect lines and pellet counting using permanently established plots. Every month, we measured grass height commonly preferred by Swayne's hartebeest in grassland habitat. Starting from the first week of burning, we recorded the abundance of Swayne's hartebeest in both burned and unburned grassland patches. RESULTS: From detected pellets, 94.3% were recorded in the grassland habitat indicating that other habitat types are less used despite their extensive cover > 50% of the Park. During wet and early dry seasons, Swayne's hartebeest exclusively preferred grassland habitat. We found that 85.2% (n = 1079) and 85.3% (n = 593) of individuals observed in areas with a grass height below 30 cm during wet and early-dry seasons, respectively; while 70.9% (n = 2288) preferred grass height below 30 cm during the dry season. The density of Swayne's hartebeest in burned grassland area was higher than unburned grassland areas up to 150 days since burning. However, in unburned grassland areas, the density was initially low but showed increasing trend for consecutive days, reaching similar density with burned areas after 150 days since burning. CONCLUSION: Swayne's hartebeest exclusively preferred grassland habitat, particularly during wet and early-dry seasons, shortest available grass height in all seasons and were attracted to burned grassland areas. Our results suggested that fire played an important role in maintaining habitat quality in grassland, and that management should continue using controlled burning as a tool for the conservation of Swayne's hartebeest. However, we remain cautious of our findings given the paucity of information regarding other confounding factors and the absence of long-term data on fire disturbance.


Assuntos
Antílopes , Ecossistema , Animais , Etiópia , Pradaria , Parques Recreativos , Estações do Ano
4.
Ecol Evol ; 14(4): e11235, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38623519

RESUMO

Habitat suitability models have become a valuable tool for wildlife conservation and management, and are frequently used to better understand the range and habitat requirements of rare and endangered species. In this study, we employed two habitat suitability modeling techniques, namely Boosted Regression Tree (BRT) and Maximum Entropy (Maxent) models, to identify potential suitable habitats for the endangered mountain nyala (Tragelaphus buxtoni) and environmental factors affecting its distribution in the Arsi and Ahmar Mountains of Ethiopia. Presence points, used to develop our habitat suitability models, were recorded from fecal pellet counts (n = 130) encountered along 196 randomly established transects in 2015 and 2016. Predictor variables used in our models included major landcover types, Normalized Difference Vegetation Index (NDVI), greenness and wetness tasseled cap vegetation indices, elevation, and slope. Area Under the Curve model evaluations for BRT and Maxent were 0.96 and 0.95, respectively, demonstrating high performance. Both models were then ensembled into a single binary output highlighting an area of agreement. Our results suggest that 1864 km2 (9.1%) of the 20,567 km2 study area is suitable habitat for the mountain nyala with land cover types, elevation, NDVI, and slope of the terrain being the most important variables for both models. Our results highlight the extent to which habitat loss and fragmentation have disconnected mountain nyala subpopulations. Our models demonstrate the importance of further protecting suitable habitats for mountain nyala to ensure the species' conservation.

5.
BMC Ecol Evol ; 24(1): 83, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38902600

RESUMO

BACKGROUND: Understanding the distribution pattern of species and their suitable habitat is key to focus conservation efforts. Climate change has had notable impact on the distribution and extent of suitable habitats, and the long-term survival of various species. We aim to determine the distribution and extent of suitable habitats for Tauraco ruspolii and T. leucotis in Ethiopia and predict their range in the 2050s and 2070s using MaxEnt algorithm. We used 25 and 29 rarified occurrence points for T. ruspolii and T. leucotis, respectively, and 13 environmental variables. Three regularization multipliers and two cut-off thresholds were used to map the potential suitable habitats for each species under current and future climates. Maps were assembled from these techniques to produce final composite tertiary maps and investigated the habitat suitability overlap between the two species using the UNION tool in the geographical information system. RESULT: All model run performances were highly accurate for both species. Precipitation of the driest month and vegetation cover are the most influential variables for the habitat suitability of T. ruspolii. The habitat suitability of T. leucotis is also mainly influenced by mean temperature of the driest quarter and vegetation cover. Under the current climate, the suitable habitat predicted for T. ruspolii covered about 24,639.19 km2, but its range size change shows a gain and increase by 156.00% and 142.68% in 2050 and 2070, respectively. The T. leucotis's current suitable habitat ranges about 204,397.62 km², but this is reduced by 40.84% and 68.67% in 2050 and 2070, respectively. Our modeling also showed that there was suitable habitat overlap between them at the margin of their respective habitat types in time series. CONCLUSION: We concluded that there is a direct or indirect impact of climate change on the suitable habitat range expansion for T. ruspolii and contraction for T. leucotis as well as overlapping of these turaco species in different regions of Ethiopia. Therefore, understanding the distribution of current and future suitable habitats of the two turaco species can provide valuable information to implement conservation practices for the species and the regions as well.


Assuntos
Mudança Climática , Ecossistema , Etiópia , Animais , Conservação dos Recursos Naturais
6.
Nat Commun ; 15(1): 172, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172616

RESUMO

Several African mammals exhibit a phylogeographic pattern where closely related taxa are split between West/Central and East/Southern Africa, but their evolutionary relationships and histories remain controversial. Bushpigs (Potamochoerus larvatus) and red river hogs (P. porcus) are recognised as separate species due to morphological distinctions, a perceived lack of interbreeding at contact, and putatively old divergence times, but historically, they were considered conspecific. Moreover, the presence of Malagasy bushpigs as the sole large terrestrial mammal shared with the African mainland raises intriguing questions about its origin and arrival in Madagascar. Analyses of 67 whole genomes revealed a genetic continuum between the two species, with putative signatures of historical gene flow, variable FST values, and a recent divergence time (<500,000 years). Thus, our study challenges key arguments for splitting Potamochoerus into two species and suggests their speciation might be incomplete. Our findings also indicate that Malagasy bushpigs diverged from southern African populations and underwent a limited bottleneck 1000-5000 years ago, concurrent with human arrival in Madagascar. These results shed light on the evolutionary history of an iconic and widespread African mammal and provide insight into the longstanding biogeographic puzzle surrounding the bushpig's presence in Madagascar.


Assuntos
Mamíferos , Humanos , Animais , Suínos , Madagáscar , Filogenia , Porosidade , Filogeografia , Mamíferos/genética
7.
Conserv Biol ; 27(6): 1344-54, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24001054

RESUMO

Conservation scientists are increasingly focusing on the drivers of human behavior and on the implications of various sources of uncertainty for management decision making. Trophy hunting has been suggested as a conservation tool because it gives economic value to wildlife, but recent examples show that overharvesting is a substantial problem and that data limitations are rife. We use a case study of trophy hunting of an endangered antelope, the mountain nyala (Tragelaphus buxtoni), to explore how uncertainties generated by population monitoring and poaching interact with decision making by 2 key stakeholders: the safari companies and the government. We built a management strategy evaluation model that encompasses the population dynamics of mountain nyala, a monitoring model, and a company decision making model. We investigated scenarios of investment into antipoaching and monitoring by governments and safari companies. Harvest strategy was robust to the uncertainty in the population estimates obtained from monitoring, but poaching had a much stronger effect on quota and sustainability. Hence, reducing poaching is in the interests of companies wishing to increase the profitability of their enterprises, for example by engaging community members as game scouts. There is a threshold level of uncertainty in the population estimates beyond which the year-to-year variation in the trophy quota prevented planning by the safari companies. This suggests a role for government in ensuring that a baseline level of population monitoring is carried out such that this level is not exceeded. Our results illustrate the importance of considering the incentives of multiple stakeholders when designing frameworks for resource use and when designing management frameworks to address the particular sources of uncertainty that affect system sustainability most heavily. Incentivando el Monitoreo y el Cumplimiento en la Caza de Trofeos.


Assuntos
Conservação dos Recursos Naturais/métodos , Atividades Humanas/psicologia , Motivação , Animais , Antílopes/fisiologia , Distinções e Prêmios , Espécies em Perigo de Extinção , Humanos , Densidade Demográfica
8.
Ecol Evol ; 13(9): e10481, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37711498

RESUMO

Fruit bats serve as crucial bioindicators, seed dispersers, pollinators, and contributors to food security within ecosystems. However, their population and distribution were threatened by climate change and anthropogenic pressures. Understanding the impacts of these pressures through mapping distribution and habitat suitability is crucial for identifying high-priority areas and implementing effective conservation and management plans. We predicted the distribution and extent of habitat suitability for Rousettus aegyptiacus and Epomophorus labiatus under climate change scenarios using average predictions from four different algorithms to produce an ensemble model. Seasonal precipitation, population index, land-use land cover, vegetation, and the mean temperature of the driest quarter majorly contributed to the predicted habitat suitability for both species. The current predicted sizes of suitable habitats for R. aegyptiacus and E. labiatus were varied, on average 60,271.4 and 85,176.1 km2, respectively. The change in species range size for R. aegyptiacus showed gains in suitable areas of 24.4% and 22.8% in 2050 and 2070, respectively. However, for E. labiatus, suitable areas decreased by 0.95% and 2% in 2050 and 2070, respectively. The range size change of suitable areas between 2050 and 2070 for R. aegyptiacus and E. labiatus shows losses of 1.5% and 1.2%, respectively. The predicted maps indicate that the midlands and highlands of southern and eastern Ethiopia harbor highly suitable areas for both species. In contrast, the areas in the northern and central highlands are fragmented. The current model findings show that climate change and anthropogenic pressures have notable impacts on the geographic ranges of two species. Moreover, the predicted suitable habitats for both species are found both within and outside of their historical ranges, which has important implications for conservation efforts. Our ensemble predictions are vital for identifying high-priority areas for fruit bat species conservation efforts and management to mitigate climate change and anthropogenic pressures.

9.
Primate Biol ; 10(2): 13-23, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38039330

RESUMO

The size and density of a population are essential parameters in primate ecology and conservation. Such information, however, is still scarce for many forest primate species. The Djaffa Mountains guereza (Colobus guereza gallarum) is an endemic Ethiopian taxon for which data about its distribution and population size are missing. Therefore, we aimed to estimate the abundance and population size of the Djaffa Mountains guereza in four forests in the Ahmar Mountains southeast of the Ethiopian Rift Valley. We conducted line-transect surveys in the forests. Within an area of 183 km2, we sampled 19 transects covering a distance of 75.9 km. We encountered 73 guereza clusters which most likely represent social groups. Since the detection distances and cluster sizes did not differ among the four forests, we applied a conventional distance sampling (CDS) model and estimated a population density of 20.6 clusters per square kilometer, i.e., 109.6 individuals per square kilometer or 20 061 individuals within the complete study area. This abundance is relatively high compared to other C. guereza taxa. However, given that the habitat and population of C. g. gallarum are already highly fragmented, further monitoring of the population and exploration of the possibilities of reconnecting its habitat should be priorities for the conservation of this taxon.

10.
BMC Ecol Evol ; 23(1): 65, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37919657

RESUMO

BACKGROUND: Climate change coupled with other anthropogenic pressures may affect the extent of suitable habitat for species and thus their distributions. This is particularly true for species occupying high-altitude habitats such as the gelada (Theropithecus gelada) of the Ethiopian highlands. To explore the impact of climate change on species distributions, Species Distribution Modelling (SDM) has been extensively used. Here we model the current and future extent of sutibale habitat for geladas. Our modelling was based on 285 presence locations of geladas, covering their complete current distribution. We used different techniques to generate pseudoabsence datasets, MaxEnt model complexities, and cut-off thresholds to map the potential distribution of gelada under current and future climates (2050 and 2070). We assembled maps from these techniques to produce a final composite map. We also evaluated the change in the topographic features of gelada over the past 200 years by comparing the topography in current and historical settings. RESULTS: All model runs had high performances, AUC = 0.87-0.96. Under the current climate, the suitable habitat predicted with high certainty was 90,891 km2, but it decreased remarkably under future climates, -36% by 2050 and - 52% by 2070. However, since the habitats of geladas already extend to mountaintop grasslands, no remarkable range shifts across elevation gradients were predicted under future climates. CONCLUSIONS: Our findings indicated that climate change most likely results in a loss of suitable habitat for geladas, particularly south of the Rift Valley. Currently geladas are confined to higher altitudes and steep slopes compared to historical sightings, probably qualifying geladas as refugee species. The difference in topography is potentially associated with anthropogenic pressures that drove niche truncation to higher altitudes, undermining the climatic and topographic niche our models predicted. We recommend protecting the current habitats of geladas even when they are forecasted to become climatically unsuitable in the future, in particular for the population south of the Rift Valley.


Assuntos
Theropithecus , Animais , Ecossistema , Meio Ambiente
11.
Am J Primatol ; 74(5): 423-32, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22311711

RESUMO

Until recently, the Bale monkey (Chlorocebus djamdjamensis), an arboreal primate endemic to the southern Ethiopian highlands, remained virtually unstudied, and its distribution pattern inadequately documented. To broaden our knowledge of the species' distribution and abundance, we carried out interviews with local people and total count surveys for Bale monkeys across 67 fragmented forest sites in human-dominated landscapes in the Oromia and Southern Nations, Nationalities, and People's Regions, Ethiopia. From January 2010 to May 2011, we discovered 26 new Bale monkey populations inhabiting forest fragments at elevations ranging from 2,355 to 3,204 m asl. Across these populations, we recorded 37 groups ranging in size from 9 to 29 individuals (Mean = 19.5, SD = 4.5), for a total of 722 individuals. Black-and-white colobus monkeys (Colobus guereza) were sympatric with Bale monkeys at all sites, while grivet monkeys (Chlorocebus aethiops) were found only at sites where Bale monkeys did not occur. All of the newly discovered Bale monkey sites once contained bamboo forest, though at 35% of the sites bamboo forest had been eliminated during the past two decades. The persistence of Bale monkeys at fragmented sites lacking bamboo suggests greater habitat flexibility for the species than previously thought, though the long-term viability of populations both with and without bamboo remains uncertain. Human hunting in response to crop raiding, a behavior the monkeys engaged in at all sites, represents a major threat facing the newly discovered Bale monkey populations. Furthermore, despite their current lack of sympatry, apparently hybrid individuals between Bale monkeys and grivets were noted at three sites, posing yet another potential obstacle to Bale monkey conservation. Community conservation programs aimed at (1) protecting remaining habitat fragments, (2) planting bamboo and trees within and between fragments, and (3) reducing crop raiding represent the only hope for survival of the newly discovered Bale monkey populations.


Assuntos
Cercopithecinae/fisiologia , Chlorocebus aethiops/genética , Conservação dos Recursos Naturais , Ecossistema , Hibridização Genética , Animais , Cercopithecinae/genética , Etiópia , Comportamento Alimentar , Glicoproteínas de Membrana , Densidade Demográfica , Receptores de Interleucina-1
12.
R Soc Open Sci ; 6(8): 190013, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31598226

RESUMO

Shade coffee farming has been promoted as a means of combining sustainable coffee production and biodiversity conservation. Supporting this idea, similar levels of diversity and abundance of birds have been found in shade coffee and natural forests. However, diversity and abundance are not always good indicators of habitat quality because there may be a lag before population effects are observed following habitat conversion. Therefore, other indicators of habitat quality should be tested. In this paper, we investigate the use of two biomarkers: fluctuating asymmetry (FA) of tarsus length and rectrix mass, and feather growth bars (average growth bar width) to characterize the habitat quality of shade coffee and natural forests. We predicted higher FA and narrower feather growth bars in shade coffee forest versus natural forest, indicating higher quality in the latter. We measured and compared FA in tarsus length and rectrix mass and average growth bar width in more than 200 individuals of five bird species. The extent of FA in both tarsus length and rectrix mass was not different between the two forest types in any of the five species. Similarly, we found no difference in feather growth between shade coffee and natural forests for any species. Therefore, we conclude our comparison of biomarkers suggests that shade coffee farms and natural forests provide similar habitat quality for the five species we examined.

13.
Primate Biol ; 6(1): 7-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32110714

RESUMO

Black-and-white colobus (Colobus guereza Rüppell, 1835) are arboreal Old World monkeys inhabiting large parts of the deciduous and evergreen forests of sub-Saharan Africa. Two of the eight subspecies of Colobus guereza are endemic to Ethiopia: C. g. gallarum and C. g. guereza. However, the validity of the Ethiopian taxa is debated and observed morphological differences were attributed to clinal variation within C. g. guereza. To date, no molecular phylogeny of the Ethiopian guerezas is available to facilitate their taxonomic classification. We used mitochondrial DNA markers from 94 samples collected across Ethiopia to reconstruct a phylogeny of respective mitochondrial lineages. In our phylogenetic reconstruction, augmented by orthologous sequence information of non-Ethiopian black-and-white colobus from GenBank, we found two major Ethiopian mitochondrial clades, with one being largely congruent with the distribution of C. g. guereza. The second clade was found only at two locations in the eastern part of the putative range of C. g. gallarum. This second lineage clustered with the lowland form, C. g. occidentalis, from central Africa, whereas the C. g. guereza lineages clustered with C. g. caudatus and C. g. kikuyuensis from Kenya and northern Tanzania. These two guereza lineages diverged around 0.7 million years ago. In addition, mitochondrial sequence information does not support unequivocally a distinction of C. g. caudatus and C. g. kikuyuensis. Our findings indicate a previous biogeographic connection between the ranges of C. g. occidentalis and C. g. gallarum and a possible secondary invasion of Ethiopia by members of the C. g. guereza-C. g. caudatus-C. g. kikuyuensis clade. Given these phylogenetic relationships, our study supports the two-taxa hypothesis, making C. g. gallarum an Ethiopian endemic, and, in combination with the taxon's very restricted range, makes it one of the most endangered subspecies of black-and-white colobus.

14.
R Soc Open Sci ; 6(9): 190772, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31598305

RESUMO

African wolves (AWs) are sympatric with endangered Ethiopian wolves (EWs) in parts of their range. Scat analyses have suggested a dietary overlap between AWs and EWs, raising the potential for exploitative competition, and a possible conservation threat to EWs. However, in contrast to that of the well-studied EW, the foraging ecology of AWs remains poorly characterized. Accordingly, we studied the foraging ecology of radio-collared AWs (n = 11 individuals) at two localities with varying levels of anthropogenic disturbance in the Ethiopian Highlands, the Guassa-Menz Community Conservation Area (GMCCA) and Borena-Saynt National Park (BSNP), accumulating 845 h of focal observation across 2952 feeding events. We also monitored rodent abundance and rodent trapping activity by local farmers who experience conflict with AWs. The AW diet consisted largely of rodents (22.0%), insects (24.8%), and goats and sheep (24.3%). Of the total rodents captured by farmers using local traps during peak barley production (July to November) in GMCCA, averaging 24.7 ± 8.5 rodents/hectare/day, 81% (N = 3009) were scavenged by AWs. Further, of all the rodents consumed by AWs, most (74%) were carcasses. These results reveal complex interactions between AWs and local farmers, and highlight the scavenging niche occupied by AWs in anthropogenically altered landscapes in contrast to the active hunting exhibited by EWs in more intact habitats. While AWs cause economic damage to local farmers through livestock predation, they appear to play an important role in scavenging pest rodents among farmlands, a pattern of behaviour which likely mitigates direct and indirect competition with EWs. We suggest two routes to promote the coexistence of AWs and EWs in the Ethiopian highlands: local education efforts highlighting the complex role AWs play in highland ecosystems to reduce their persecution, and enforced protection of intact habitats to preserve habitat preferred by EWs.

15.
Sci Rep ; 9(1): 14243, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578447

RESUMO

In our most recent study, we found that in Tanzania infection with Treponema pallidum (TP) subsp. pertenue (TPE) is present in four different monkey species. In order to gain information on the diversity and epidemiological spread of the infection in Tanzanian nonhuman primates (NHP), we identified two suitable candidate genes for multi-locus sequence typing (MLST). We demonstrate the functionality of the MLST system in invasively and non-invasively collected samples. While we were not able to demonstrate frequent interspecies transmission of TPE in Tanzanian monkeys, our results show a clustering of TPE strains according to geography and not host species, which is suggestive for rare transmission events between different NHP species. In addition to the geographic stability, we describe the relative temporal stability of the strains infecting NHPs and identified multi-strain infection. Differences between TPE strains of NHP and human origin are highlighted. Our results show that antibiotic resistance does not occur in Tanzanian TPE strains of NHP origin.


Assuntos
Cercopithecus/microbiologia , Chlorocebus aethiops/microbiologia , Especificidade de Hospedeiro , Doenças dos Macacos/transmissão , Papio anubis/microbiologia , Papio cynocephalus/microbiologia , Treponema/classificação , Infecções por Treponema/veterinária , Animais , Doenças dos Símios Antropoides/epidemiologia , Doenças dos Símios Antropoides/microbiologia , Doenças dos Símios Antropoides/transmissão , Congo/epidemiologia , Fezes/microbiologia , Estudos de Associação Genética , Variação Genética , Gorilla gorilla/microbiologia , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/microbiologia , Tipagem de Sequências Multilocus , Filogenia , Polimorfismo de Nucleotídeo Único , Especificidade da Espécie , Tanzânia/epidemiologia , Treponema/genética , Treponema/isolamento & purificação , Infecções por Treponema/epidemiologia , Infecções por Treponema/microbiologia , Infecções por Treponema/transmissão
16.
J Wildl Dis ; 54(1): 175-179, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29048263

RESUMO

: We captured 14 individual African wolves ( Canis lupaster) a total of 16 times in the Ethiopian Highlands in April 2015 and March 2016 by using rubber-lined foothold traps and immobilized them with dexmedetomidine-ketamine. Traps were baited with sheep meat and surveyed every 2 h. Capture efficiency (number of captures per number of visits) was 0.94, and capture rate (number of captures per number of trap nights) was 0.24. Trapped wolves were immobilized with 0.025 mg/kg dexmedetomidine and 8-10 mg/kg ketamine on the basis of respective estimated body mass. Mean (SD) induction times were 3.4 (0.5) min for subadults ( n=4), 3.5 (0.3) min for adult males ( n=4), and 4.7 (1.0) min for adult females ( n=6). Inductions were calm, muscle relaxation was good, and all animals were completely immobilized. Apart from increased rectal temperatures, no major negative side effects were observed. Atipamezole at 10 mg intramuscularly per milligram of dexmedetomidine administered was used for reversal at a mean of 43.5 (7.7) min after administration of dexmedetomidine-ketamine. Recoveries were relatively smooth, and animals were on feet, leaving the site within a mean of 13.6 (3.9) min, after atipamezole administration. Our results indicate that African wolves can be safely captured and immobilized by using rubber-lined foothold traps and dexmedetomidine and ketamine.


Assuntos
Dexmedetomidina/farmacologia , Ketamina/farmacologia , Restrição Física/veterinária , Lobos , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Animais , Animais Selvagens , Dexmedetomidina/administração & dosagem , Etiópia , Feminino , Imidazóis/farmacologia , Ketamina/administração & dosagem , Masculino
17.
R Soc Open Sci ; 5(5): 172207, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29892409

RESUMO

Carnivore populations are declining globally due to range contraction, persecution and prey depletion. One consequence of these patterns is increased range and niche overlap with other carnivores, and thus an elevated potential for competitive exclusion. Here, we document competition between an endangered canid, the Ethiopian wolf (EW), and the newly discovered African wolf (AW) in central Ethiopia. The diet of the ecological specialist EW was dominated by rodents, whereas the AW consumed a more diverse diet also including insects and non-rodent mammals. EWs used predominantly intact habitat, whereas AWs used mostly areas disturbed by humans and their livestock. We observed 82 encounters between the two species, of which 94% were agonistic. The outcomes of agonistic encounters followed a territory-specific dominance pattern, with EWs dominating in intact habitat and AWs in human-disturbed areas. For AWs, the likelihood of winning encounters also increased with group size. Rodent species consumed by EWs were also available in the human-disturbed areas, suggesting that these areas could be suitable habitat for EWs if AWs were not present. Increasing human encroachment not only affects the prey base of EWs, but also may impact their survival by intensifying competition with sympatric AWs.

18.
PLoS One ; 13(8): e0202303, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30138418

RESUMO

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.


Assuntos
DNA Mitocondrial , Variação Genética , Theropithecus/genética , Distribuição Animal , Animais , Evolução Biológica , Citocromos b/genética , Feminino , Haplótipos , Papio/genética , Filogenia , Filogeografia , Densidade Demográfica
19.
PLoS One ; 6(1): e16385, 2011 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-21298107

RESUMO

The Egyptian jackal (Canis aureus lupaster) has hitherto been considered a large, rare subspecies of the golden jackal (C. aureus). It has maintained its taxonomical status to date, despite studies demonstrating morphological similarities to the grey wolf (C. lupus). We have analyzed 2055 bp of mitochondrial DNA from C. a. lupaster and investigated the similarity to C. aureus and C. lupus. Through phylogenetic comparison with all wild wolf-like canids (based on 726 bp of the Cytochrome b gene) we conclusively (100% bootstrap support) place the Egyptian jackal within the grey wolf species complex, together with the Holarctic wolf, the Indian wolf and the Himalayan wolf. Like the two latter taxa, C. a. lupaster seems to represent an ancient wolf lineage which most likely colonized Africa prior to the northern hemisphere radiation. We thus refer to C. a. lupaster as the African wolf. Furthermore, we have detected C. a. lupaster individuals at two localities in the Ethiopian highlands, extending the distribution by at least 2,500 km southeast. The only grey wolf species to inhabit the African continent is a cryptic species for which the conservation status urgently needs assessment.


Assuntos
Espécies em Perigo de Extinção , Lobos/classificação , África , Animais , Conservação dos Recursos Naturais , DNA Mitocondrial/isolamento & purificação , Filogenia , Lobos/genética
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