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Identification Of Demographic Structure And Population Viability Analysis Of Gazella Subgutturosa In SanliurfaCobanoglu, Aziz Emre 01 February 2010 (has links) (PDF)
Goitered gazelle (Gazella subgutturosa) is an Asian antelope species and it is classified as Vulnerable by IUCN. They have an economic, esthetic and cultural value / therefore, they had been hunted and domesticated for a long time. Additional human disturbance over years nearly led goitered gazelle populations in Turkey to extinction. Today in Turkey, only natural population of goitered gazelle lives in Sanlurfa.
In this theses, demographic structure and population parameters of natural population goitered gazelle in Sanliurfa is studied. Line transect and regular surveys are performed to collect data about demographic structure of the population such as sex ratio and group composition. Line transect sampling, which is a distance sampling technique, is used to estimate population size and density of the population. GPS collared goitered gazelles are monitored for fecundity and survival rate.
Data is collected for 18 from July 2008 to December 2009 during 32 field surveys. Four main transect samplings have been performed and including transect samplings that are done during regular surveys, 90 line transects are walked.
Population sizes and densities were estimated to be (average ± / standard error) 242 ± / 184 and 2.302 ± / 1.590 individual per km2 for July 2008 / 365 ± / 179 and 3.476 ± / 1.707 individual per km2 for January 2009 / 319 ± / 111 and 3.039 ± / 1.059 individual per km2 for June 2009 and lastly, 317 ± / 243 and 3.019 ± / 2.315 for November 2009. Survival rate is estimated to be 0.276, 0.540 and 0.585 for calves, 1 year old and 2+ years olds respectivelty, and fecundity is estimated to be 0.4.
This preliminary study shows that according to Population Viability Analysis results, natural goitered gazelle population in Turkey will be extinct in next 10 years if more effective conservation is not performed.
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Estimation Of Demography And Seasonal Habitat Use Patterns Of Anatolian Mouflon (ovis Gmelinii Anatolica) In Konya Bozdag Protection Area Using Distance SamplingOzdirek, Lutfiye 01 September 2009 (has links) (PDF)
The Anatolian mouflon (Ovis gmelinii anatolica) is an endemic ungulate subspecies and of IUCN Vulnerable status that inhabits Konya-Bozdag region located in Central
Anatolia.
In this thesis, the demography and habitat use of the only natural population of Anatolian mouflon at Konya-Bozdag Provice is studied. Throughout the study, distance sampling techniques, specifically line transect sampling, are used to
estimate density, size and growth rate of this population. Sex, age and count data are used to estimate relevant parameters. Changes in population structure and seasonal
area use are monitored for two years.
Data is collected during repeated random line transects from May 2007 to July 2009. Line transect method is preferred since it requires less effort and is less expensive when compared to the complicated techniques that need animal marking or radio tagging.
In total, 78 transect lines were surveyed during the time which covers 3 lambing periods. In spite of the paratuberculosis epidemics in the fenced area which has
affected the population adversely in the previous years, a rather stable population trend is observed.
The post-breeding population size in 2007, 2008 and 2009 were estimated to be 883+-241, 939+-136, 972+-243 (average+-satndard error) and densities as 27.227, and 28.186 individuals per sq km, respectively.
Growth rate of population is found using the ratio of the population size estimates of consecutive years from 2007 to 2009, average 1.0495+-0.0203.
Habitat use patterns of the Anatolian mouflon throughout the study period are investigated according to seasons and sex groups. There is sexual segregation in the Anatolian mouflon population in Konya Bozdag Province, with the females using the western part and males using the eastern part of Bagderesi. Seasonal patterns affect on the area use of animals, group formation and compositions and the relationship between them are searched throughout the study. The movements of the individuals and groups followed seasonal patterns as centers of activities changed according to seasons.
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New insights into ecology and conservation status of Bawean deer (Axis kuhlii) and red muntjac (Muntiacus muntjak) in Indonesian tropical rainforest / De nouvelle données sur l'écologie et le status de conservation du cerf du Bawean (Axis kuhlii) et du muntjac (Muntiacus muntjak) vivant dans les forêts tropicales d'IndonésieRahman, Dede Aulia 23 September 2016 (has links)
Les objectifs de cette étude consistaient d'une part à étudier l'écologie de deux cerf tropical de taille moyenne, le cerf de Bawean Axis kuhlii et le Muntjac Muntiacus muntjac dans la réserve naturelle et sanctuaire de la vie sauvage de l'île de Bawean et le parc national d'Ujung Kulon respectivement, et d'autre part de mettre à jour leur statut de conservation. Nous avons utilisé pour la première fois une nouvelle technique de contrôle, les caméras-pièges, associées à aux méthodes écologiques classiques afin d'évaluer la taille des populations, d'examiner l'utilisation de l'habitat, d'estimer le domaine utilisé et d'identifier les patrons d'activité. Les résultats montrent que si les caméra-pièges sont couteuses au départ, elles ont facilité le recueil de données sur le terrain et ont fourni beaucoup d'informations pour les analyses ultérieures. De plus, la méthode des caméra-pièges a permis d'acquérir un plus grand nombre d'informations sur espèces étudiées mais aussi sur les autres espèces présentes sur les sites, que les autres méthodes employées. Pour l'estimation des tailles de population nous avons utilisé un modèle de rencontre aléatoire (REM), une technique efficace pour évaluer la densité d'espèce élusives, rares et dont les individus ne sont pas reconnaissables individuellement. Ce qui ne peut être obtenu par la technique de capture-recapture photographique qui requière que les individus soient identifiables et donc une grande qualité photographique. Les résultats ont été comparés avec ceux obtenus par la technique de comptage de tas de fèces. Les deux méthodes ont fourni des évaluations de densité de population semblables, plus élevées durant la saison sèche et une taille de population estimée entre 227 et 416 cerfs de Bawean. L'étendue de l'aire utilisée par le cerf de Bawean est apparue considérablement plus réduite que lors des précédentes estimations, le comptage de tas de fèces ayant fourni des données complémentaires aux images issues des caméra-pièges. Les deus espèces de cervidés ont essentiellement été relevées dans des habitats de forêt secondaire. L'analyse faite par la méthode de l'entropie maximale (Maxent) a montré que les variables anthropogéniques (pour les deux espèces) et climatiques (Muntjac seulement) sont les prédicteurs principaux pour l'utilisation de l'habitat. Enfin, en utilisant les indicateurs horaires fournis par les caméra-pièges, les patrons d'activité ont été examinés en relation avec le sexe et les conditions environnementales. Bien qu'il soit considéré comme espèce nocturne, l'essentiel des clichés de cerf de Bawean ont été pris durant le jour, et l'activité nocturne dépend de la luminosité. Le muntjac a également témoigné d'une certaine activité diurne avec les plus forts pics situés après le lever et avant le coucher de soleil, alors que l'activité nocturne n'est pas apparue liée à la luminosité. Il n'a pas été observé de différences entre mâles et femelles pour les deux espèces. Alors que le statut du muntjac est classé "peu préoccupant" par UICN, même si des mesures locales de conservation devraient être prises dans la zone d'étude, le cerf de Bawean devrait être maintenu dans la catégorie "en danger critique" car cette population qui apparaît toujours aussi réduite est toujours soumise à une perte d'habitat par déforestation illégale et à des perturbations par les chiens et les chasseurs. / The aim of this study was to investigate the ecology of two medium-sized tropical deer, the Bawean deer Axis kuhlii and the red muntjac Muntiacus muntjac in Bawean Island Nature Reserve and Wildlife Sanctuary and Ujung Kulon National Park respectively, and to update their conservation status. We used for the first time a new monitoring technique, camera trapping, together with classical ecological field methods for estimating population size, investigating habitat use, predicting range, and identifying activity pattern. Results show that camera traps were initially expensive but they lightened the field work and provided much information for further analyses. Moreover, camera trapping provided a higher number of records and accurate species identification than other methods. For estimating population size we used a random encounter model (REM), a technique accurate for estimating density of elusive, rare and unmarked species contrary to photographic capture-recapture techniques which require both unique mark and good photographs for individual recognition, and compared the results with those obtained by faecal pellet group count. Both methods provided similar population density estimates, higher in the dry than in the wet season, and a population size of ca. 227-416 deer. The range of Bawean deer established dramatically narrower than previously reported, faecal pellet group count bringing additional data to camera trapping. Both deer species were mainly recorded in secondary forests; Analysis with Maximum entropy model (Maxent) showed that anthropogenic (for both species) and climatic (for red muntjac only) variables were the main predictors of habitat use. Finally, using time data recorded by camera traps, we investigated the activity pattern related to sex and environmental conditions. The believed nocturnal Bawean deer was predominantly photographed during the day, and its nocturnal activity was linked to luminosity. Red muntjac also showed some diurnal activity with higher peaks after sunrise and before sunset, and a nocturnal activity which was not influenced by luminosity. No difference was observed between males and females for both species. Whereas red muntjac is listed "Least concern" by IUCN even if local conservation measures should be undertaken in our study area, Bawean deer should remain "Critically endangered" as the population is still small and the main threats, habitat loss due to illegal logging and human disturbance by dogs and hunters, are ongoing.
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