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Wronski T.,Zoological Society of London | Wronski T.,King Khalid Wildlife Research Center | Plath M.,Goethe University Frankfurt
Journal of Zoology | Year: 2010

Mountain gazelle Gazella gazella in Saudi Arabia are listed as 'vulnerable' by the IUCN. At present, the species' survival is secured by extensive captive-breeding programmes and reintroductions into protected areas. Two reintroduction attempts (Ibex Reserve and Uruq Bani Ma'Arid protected areas) in Saudi Arabia have been undertaken in the past two decades. Post-monitoring of released individuals is essential for the success of such reintroduction programmes; however, cryptic species like mountain gazelles are extremely difficult to observe directly. As radio-tracking is a cost-intensive and invasive post-monitoring technique, we asked: how can reintroduced or remnant pockets of natural gazelle populations be monitored indirectly? Here, we propose the use of latrine mapping as an effective, cost-efficient and non-invasive tool to survey the social organization of reintroduced mountain gazelles as an indicator for repatriation success. In this study, we used released radio-collared animals to characterize the spatial distribution of latrines within female group home ranges. Distance to the next latrine, latrine size, as well as numbers of fresh faecal pellet groups per latrine or presence of urination marks were used as dependent variables for step-wise backward multiple regressions and were correlated with various ecological factors. Most dependent variables were correlated with distance or direction from the nearest tree, but not indicative of home-range cores. Only latrine densities were distinctly higher in core areas of female group home ranges, and no pattern of peripheral marking was detected. Hence, latrine density is a good indicator of home-range use in female group home ranges. Mapping latrines and determining latrine densities are therefore the methods of choice to survey mountain gazelle populations. © 2009 The Zoological Society of London. Source


Wronski T.,King Khalid Wildlife Research Center
Zoology in the Middle East | Year: 2010

In the Red Sea, pearl oyster banks occur most extensively around the Dahlak and the Farasan Islands. Pearl oysters (Pinctada, Pteriidae) form extended beds by attaching themselves to hard substrates. Such beds attract a diverse bio-fouling fauna. Most dominant are the molluscs, but little is known about the associated biota of pearl oyster beds, their distributional abundance, and the structure of this community. In this study, the macro-molluscan fauna living on pearl oyster beds in the Red Sea around the Farasan Islands was studied using a quantitative survey of the by-catch left by pearl oyster divers. Bivalvia represented 99.6% of the malaco-fauna on pearl oyster beds around the Farasan Islands, while gastropods and chitons represented only 0.4%. In total, 33 mollusc species were identified (24 bivalves, 7 prosobranch gastropods, one basomatophore gastropod and one chiton), with Brachidontes variabilis, a species which is not found on Arabian Gulf pearl oyster beds, the most common bivalve (71% of all molluscs), and Diodora ruppellii the most common gastropod (0.12% of all molluscs). The results are discussed and compared with the pearl oyster beds from the Arabian Gulf. © Kasparek Verlag, Heidelberg. Source


Lerp H.,Goethe University Frankfurt | Wronski T.,Zoological Society of London | Wronski T.,King Khalid Wildlife Research Center | Pfenninger M.,Goethe University Frankfurt | Plath M.,Goethe University Frankfurt
Organisms Diversity and Evolution | Year: 2011

Many species of gazelles (Gazella spp.) are nowadays threatened by hunting, poaching, habitat loss and habitat deterioration. Conservation efforts for this group not only face the problem of maintaining remnant populations, but often natural populations have been extirpated from the wild. In some cases, though, captive breeding programs exist that might provide a valuable source for future reintroductions. A major problem in this context is that phylogeographic relationships among different (potentially locally adapted) populations, and even basic phylogenetic relationships between species, are poorly understood, thus hampering the assignment of management units, breeding groups or stocks for reintroduction projects. Our present study focused on Dorcas gazelles (G. dorcas and G. saudiya) from the species' entire distribution range, with samples originating from western Saharan Africa into Saudi Arabia. In stark contrast to previous studies reporting on pronounced genetic structure in taxa such as Mountain gazelles (G. gazella), we detected low genetic diversity and no evidence for major phylogenetic lineages when analyzing two mitochondrial genetic markers. Using a coalescent approach we infer a steep population decline that started approximately 25,000 years before present and is still ongoing, which coincides with human activities in Saharan Africa. Our phylogenetic analyses, statistical parsimony network analysis and inferred colonization patterns shed doubt on the validity of various described subspecies of G. dorcas. © Gesellschaft für Biologische Systematik 2011. Source


Wronski T.,King Khalid Wildlife Research Center
Journal of Arid Environments | Year: 2010

Mountain gazelle (Gazella gazella) in Saudi Arabia is listed as 'vulnerable' by the IUCN. At present the species' survival is secured by extensive captive-breeding programs and re-introductions into protected areas. Post-monitoring of released individuals is essential for evaluating the success of such re-introductions but managers have difficulties in deciding whether food, water and other resources are sufficient to sustain a stable population. This study reports on data collected during standardized road transect counts in two wadis of the Ibex Reserve into which gazelles were previously released, and aims to compare the success of both re-introduction attempts with resource availability and home range size. Results from step-wise backward multiple regressions identified food availability and population density as significant predictors for home range size. The low amount of available food may have increased the competition between non-related females and therefore led to an increased overlap between non-group members resulting in increased dispersal rates. This information will allow interpretation of habitat suitability and provides possible reasons for the population decrease at both study sites. The data will enable conservation mangers to identify future re-introduction sites and will help improving the success of future re-introductions in Saudi Arabia or other parts of the species range. © 2010 Elsevier Ltd. Source


Omer S.A.,King Khalid Wildlife Research Center | Adam S.E.I.,University of Khartoum | Mohammed O.B.,King Khalid Wildlife Research Center
Research Journal of Medicinal Plant | Year: 2011

Ethanolic and ether extracts of Commiphora myrrha were evaluated for their antimicrobial activity against two Gram negative organisms (.Escherichia coli and Pseudomonas aeruginosa), two Gram positive organisms (Bacillus subtilis and Staphylococcus albus) and fungi represented by Candida albicans isolated from gazelles held at King Khalid Wildlife Research Centre, Thumamah. The method used in evaluation of the antimicrobial activity was the two-layer agar diffusion method. The ethanolic extract of C. myrrha exhibited antimicrobial activity against the Gram negative organisms investigated together with S. albus. On the other hand, the ether extract showed antimicrobial activity against Gram positive organisms investigated and against Candida albicans, with the antifungal activity being greater. The minimum inhibitory concentration of the ethanolic extract against P. aeruginosa and E. coli was found to be 20 and 40 mg mL-1, respectively. While the minimum inhibitory concentration of the ether extract against both S. albus and C. albicans was found to be 10 and 40 mg mL-1 for B. subtilis, respectively. © 2011 Academic Journals Inc. Source

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