Letteratura scientifica selezionata sul tema "Muntjac deer"

Facing change of environmental conditions, the activity rhythm of animals may habituate. Remote cameras were used to quantify Bawean deer and red muntjac activity patterns and to examined differences by season, sex and lunar cycle to respond predator presence, in Bawean Island and Ujung Kulon National Park, Indonesia. Photographs of Bawean deer (n = 118) were taken during March to November 2014 and for red muntjac (n = 4,142) were taken during January 2013 to July 2014. Data were analyzed by using Generalized Additive Models (GAMs) to test the relationship between activity patterns and the lunar cycle, further, the pattern of daily activity overlap between deer and their predators calculated by kernel density estimation. The number of captures by camera trapping were less for both sexes of both deer in wet season. Male and female Bawean deer were active throughout the day and night during all seasons, with several activity peaks during the 24h period, while male and female red muntjac show diurnal activity levels with higher peaks 1h after sunrise until 1h before sunset. There was no significant difference in activities between males and females for both deer. The amount of nocturnal activity corresponding to differences in nocturnal luminosity for Bawean deer varied, but not for the red muntjac. Free-roaming dog and Bawean deer presented opposite peak activities, while dhole as (the predator of the red muntjac) and red muntjac were both cathemeral. The differences between the two similar-sized species could be closely related to reduction of predation risk and increasing foraging success.

Abstract The Sumatran tiger is one of the endemic species in Indonesia which has been driven to extinction. This species has been categorized as critically endangered by IUCN and as Appendix I by CITES. Loss of prey is one of the threats to the Sumatran tiger’s population. It is an essential factor to maintain the existence of the Sumatran tiger. The study aimed to reveal the abundance of the Sumatran tiger prey using the camera trap method in Way Kambas National Park where one of the Sumatran tiger’s habitats. Our study was conducted from March until August 2020. We used 16 Camera traps which were divided into 2 Sites, Resort Pengelolaan Taman Nasional (RPTN) Sekapuk and Way Kanan. We found five species of Preys. They are wild boar (Sus scrofa), Sambar deer (Rusa unicolor), pigtail macaques (Macaca nemestrina), red muntjac (Muntiacus muntjac), and Mouse deer (Tragulus kanchil). The highest number of abundance was Sus scrofa (63%), and the lowest number of abundance was Rusa unicolor (0,94%). Our findings concluded that the potential preferred prey was Sus scrofa and Muntiacus muntjac.

Numerous deer species have been introduced beyond their native range into ecosystems around the world. Their economic value leads to further accidental and deliberate releases and lack of control is contributing to range expansion in Australia, South America and Europe. Despite localised or regional concern, the scale and generality of detrimental impacts have not been widely recognised. We review the direct and indirect impacts on ecosystems and evidence for interspecific effects on native deer. In New Zealand, where large herbivores were previously absent, severe and novel impacts have been found in susceptible forests. Even where ecosystems contain native deer, invasion by taxonomically exotic deer species carries the risk of cascade effects on spatial plant dynamics and forest composition. In Patagonia, introduced deer have disrupted forest composition, whereas in Europe, ecosystem impacts of introduced species can differ from those of over-abundant native deer. Introduced Chinese muntjac (Muntiacus reevesi) within a coniferous forestry landscape in eastern England differ from native European roe deer (Capreolus capreolus) in their distribution of herbivory among differing habitats, and provide much lower rates of endozoochorous seed dispersal. Frequent concern is expressed that introduced deer species may have detrimental effects on native deer and other ungulates, although potential epidemiological effects have not been investigated. Apparent competition, with introduced prey resulting in increased predation rates on native deer, may be occurring between South American huemul (Hippocamelus bisulcus) and southern pudu (Pudu puda). Habitat and dietary overlap is often substantial among native and introduced ungulates, including deer, and exploitation competition is likely. Evidence includes spatial responses of native to non-native deer and negatively correlated changes in population abundance, but demographic mechanisms have not been demonstrated previously. In a coniferous forestry landscape in eastern England, substantial habitat and dietary overlap occurs between native roe deer and high-density introduced Chinese muntjac. This roe deer population has shown a reduction in body weight and fertility following establishment and increasing abundance of non-native Chinese muntjac, compatible with interspecific competition. European roe deer also appear susceptible to competition from larger grazing deer, including native red deer (Cervus elaphus) and introduced fallow (Dama dama). The widely introduced fallow deer may be a particularly effective competitor in sympatry with intermediate or concentrate feeders. There is need for further investigation of potential interactions of introduced and native deer species, and a wider recognition of the ecological impacts of introduced deer.

The principal aim of the study which was conducted between May 1995 and May 1997 was to collect and analyze information that would be considered vital to any future management actions that may be applied to the deer living in the wild in the Bali Barat National Park ecosystem in Indonesia. The systems approach used sought to analyze the complex interactions between the soil, plant, animal and human activity subsystems. In particular, interaction between Rusa deer and Muntjac deer was compared where possible, although the principal focus of the study was on the population of Muntjac deer. The soils in habitats frequented by deer in Bali Barat National Park were found to be of relatively low fertility status. Chemical analysis of the soil revealed that all of the mineral element contents considered in this study were in the lowest range for soils, in general. During this study the population of Muntjac deer in the Bali Barat National Park was submitted to phylogenetic analysis to determine whether the Bali population is distinct. Preliminary results indicate that these deer are apart of a diverse, but monophyletic group of Muntiacus Muntjac. The potential unique status of Muntjac deer in Bali Barat National Park, and the need to preserve them as part of the natural resource base that constitutes the Indonesian archipelago increased the importance of this study of the ecosystem and social system surrounding Bali Barat National Park.

The principal aim of the study which was conducted between May 1995 and May 1997 was to collect and analyze information that would be considered vital to any future management actions that may be applied to the deer living in the wild in the Bali Barat National Park ecosystem in Indonesia. The systems approach used sought to analyze the complex interactions between the soil, plant, animal and human activity subsystems. In particular, interaction between Rusa deer and Muntjac deer was compared where possible, although the principal focus of the study was on the population of Muntjac deer. The soils in habitats frequented by deer in Bali Barat National Park were found to be of relatively low fertility status. Chemical analysis of the soil revealed that all of the mineral element contents considered in this study were in the lowest range for soils, in general. During this study the population of Muntjac deer in the Bali Barat National Park was submitted to phylogenetic analysis to determine whether the Bali population is distinct. Preliminary results indicate that these deer are apart of a diverse, but monophyletic group of Muntiacus Muntjac. The potential unique status of Muntjac deer in Bali Barat National Park, and the need to preserve them as part of the natural resource base that constitutes the Indonesian archipelago increased the importance of this study of the ecosystem and social system surrounding Bali Barat National Park.
Doctor of Philosophy (PhD)

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