Splitting or Lumping? A Conservation Dilemma Exemplified by the Critically Endangered Dama Gazelle (Nanger dama)

Managers of threatened species often face the dilemma of whether to keep populations separate to conserve local adaptations and minimize the risk of outbreeding, or whether to manage populations jointly to reduce loss of genetic diversity and minimise inbreeding. In this study we examine genetic relatedness and diversity in three of the five last remaining wild populations of dama gazelle and a number of captive populations, using mtDNA control region and cytochrome b data. Despite the sampled populations belonging to the three putative subspecies, which are delineated according to phenotypes and geographical location, we find limited evidence for phylogeographical structure within the data and no genetic support for the putative subspecies. In the light of these data we discuss the relevance of inbreeding depression, outbreeding depression, adaptive variation, genetic drift, and phenotypic variation to the conservation of the dama gazelle and make some recommendations for its future conservation management. The genetic data suggest that the best conservation approach is to view the dama gazelle as a single species without subspecific divisions

Dama Gazelle (Nanger dama) conservation strategy 2019-2028

Produced following the workshop hosted by Al Ain Zoo in Al Ain, United Arab Emirates, 11-13 December 2018. Compiled and edited by: David Mallon, Lisa Banfield, Helen Senn & Hessa Al Qahtani.Peer reviewe

Splitting or lumping? A conservation dilemma exemplified by the critically endangered Dama Gazelle (Nanger dama)

Managers of threatened species often face the dilemma of whether to keep populations separate to conserve local adaptations and minimize the risk of outbreeding, or whether to manage populations jointly to reduce loss of genetic diversity and minimise inbreeding. In this study we examine genetic relatedness and diversity in three of the five last remaining wild populations of dama gazelle and a number of captive populations, using mtDNA control region and cytochrome b data. Despite the sampled populations belonging to the three putative subspecies, which are delineated according to phenotypes and geographical location, we find limited evidence for phylogeographical structure within the data and no genetic support for the putative subspecies. In the light of these data we discuss the relevance of inbreeding depression, outbreeding depression, adaptive variation, genetic drift, and phenotypic variation to the conservation of the dama gazelle and make some recommendations for its future conservation management. The genetic data suggest that the best conservation approach is to view the dama gazelle as a single species without subspecific divisions

Distribution potentielle des grands mammifères dans le Parc du W au Niger

Jean Claude Lefeuvre (Président) Thierry Brossard (Rapporteur) Daniel Maillard (Rapporteur) Dominique Laffly (Examinateur)The countries of West Africa protects numerous areas with a diversified fauna. But, especially on large mammals, few studies about wildlife have been performed contrarily to eastern and southern Africa where several research programs have been led for thirty years. Niger, hosts one of the oldest African fauna reserve: the W National Park. In order to allow managers to set a management policy to maintain, and even raise, the biodiversity, we developed a distribution analysis and rating method of large mammals. This method, called SAGEDOC (Spatial Analysis GEoreferenced Data Of Counts), takes into account the usually limited financial and logistic potentialities at managers disposal. The SAGEDOC method, using GIS potentialities (as space management tool) associated to contributions of remote sensing and multivariate statistics, is based on spatialised information permitting to understand the distribution of large mammals in dry season. Wildlife was considered as the central element of a geosystem which ecological and anthropic factors have various influences according to space and time. By considering this spatio-temporal variability, we could have pointed out the distribution of a great number of mammal species, socio-ecological characteristics of which are often very different.L'Afrique de l'Ouest abrite de nombreuses aires protégées au sein desquelles évolue une faune très variée. Peu d'études ont été réalisées sur la faune sauvage, et notamment sur les grands mammifères, contrairement à ce que l'on constate en Afrique orientale et australe, où plusieurs programmes ont été menés depuis une trentaine d'années. Le Niger, davantage réputé pour ses paysages désertiques dans le Ténéré, possède une des plus anciennes réserve de faune africaine : le Parc National du W.Nous avons développé une méthode d'analyse de la distribution et d'estimation des grands mammifères, permettant aux gestionnaires la mise en place d'une politique de gestion et d'aménagement dans le but de préserver voire d'augmenter la biodiversité. Cette méthode, intitulée SAGEDOC (Analyse Spatiale GEoréférencée des Données de Recensements), tient compte des moyens financiers et logistiques, souvent restreints, mis à la disposition des gestionnaires. La méthode SAGEDOC, utilisant les potentialités des SIG (en tant qu'outil de gestion de l'espace) associées aux apports de la télédétection et des statistiques multivariées, s'appuie sur les informations spatialisées qui permettent de comprendre la répartition des espèces de grands mammifères en saison sèche.La faune sauvage a été considérée comme l'élément central d'un géosystème dont les facteurs écologiques et anthropiques ont des influences variables dans l'espace et dans le temps. En tenant compte de cette variabilité spatio-temporelle, nous avons pu caractériser la distribution d'un grand nombre d'espèces de mammifères, dont les caractéristiques socioécologiques sont souvent très différentes

Oil in the Sahara: mapping anthropogenic threats to Saharan biodiversity from space

Deserts are among the most poorly monitored and understood biomes in the world, with evidence suggesting that their biodiversity is declining fast. Oil exploration and exploitation can constitute an important threat to fragmented and remnant desert biodiversity, yet little is known about where and how intensively such developments are taking place. This lack of information hinders local efforts to adequately buffer and protect desert wildlife against encroachment from anthropogenic activity. Here, we investigate the use of freely available satellite imagery for the detection of features associated with oil exploration in the African Sahelo-Saharan region. We demonstrate how texture analyses combined with Landsat data can be employed to detect ground-validated exploration sites in Algeria and Niger. Our results show that site detection via supervised image classification and prediction is generally accurate. One surprising outcome of our analyses is the relatively high level of site omission errors in Niger (43%), which appears to be due to non-detection of potentially small-scale, temporary exploration activity: we believe the repeated implementation of our framework could reduce the severity of potential methodological limitations. Overall, our study provides a methodological basis for the mapping of anthropogenic threats associated with oil exploitation that can be conducted across desert regions

Saving the Last West African Giraffe Population: A Review of Its Conservation Status and Management

The West African giraffe (Giraffa camelopardalis peralta) was historically spread across much of the Sudano-Sahelian zone but is now restricted to Niger. Several factors resulted in their dramatic decline during the late 20th century. In 1996, only 49 individuals remained, concentrated in the ‘Giraffe Zone’. Conservation activities implemented by the Government of Niger, supported by local communities and NGOs, facilitated their population numbers to increase. This review summarizes past and present conservation activities and evaluates their impact to advise and prioritize future conservation actions for the West African giraffe. The long-term conservation of the West African giraffe is highly dependent on the local communities who live alongside them, as well as supplementary support from local and international partners. Recent conservation initiatives range from community-based monitoring to the fitting of GPS satellite tags to better understand their habitat use, spatial movements to expansion areas, and environmental education to the establishment of the first satellite population of West African giraffe in Gadabedji Biosphere Reserve, the latter serving as a flagship for the future restoration of large mammal populations in West Africa. The integration of modern technologies and methods will hopefully provide better-quality data, improved spatial analyses, and greater understanding of giraffe ecology to inform the long-term management of West African giraffe