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1.
J Zoo Wildl Med ; 53(4): 844-854, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36640089

RESUMEN

Neoplasia is a common cause of morbidity and mortality in captive nondomestic felids. Seven tigers (Panthera tigris), two African lions (Panthera leo), and two snow leopards (Panthera uncia) were diagnosed with melanocytic neoplasia (10 malignant melanomas, two benign melanocytomas) over a 20-yr period. Animals were 10-19 yr old and 5/7 tigers were phenotypically white. Malignant melanoma tumor location included skin (n = 4), oral mucosa (n = 2), nasal planum (n = 1), iris/uvea (n = 2), and lip margin (n = 1); melanocytomas were found in skin (n = 2). Metastasis to regional lymph nodes was seen at diagnosis in 3/7 melanoma cases. Thoracic radiography (n = 6) and/or computed tomography (n = 2) did not detect pulmonary metastasis at diagnosis but were useful for detection later in the disease course. Median survival time (MST) for all cases ranged from 1 mon - 40 mon. Seven cases with malignant melanoma underwent treatment, which included surgery, radiation therapy, and administration of the canine melanoma vaccine (Oncept®) or a combination of these treatments; MST was 5-40 mon for these cases. While multimodal therapy may provide an improved survival time, the majority of animals with malignant melanoma invariably died from neoplastic disease. Necropsy confirmed metastasis of malignant melanoma in 7/9 animals; sites included lung, liver, lymph node, kidney, mesentery, pleural cavity, heart, stomach, spleen, and adrenal gland. This case series describes the clinical and histologic findings of melanocytic neoplasia in nondomestic felids as well as multimodal treatment strategies incorporating the canine melanoma vaccine.


Asunto(s)
Enfermedades de los Perros , Felidae , Leones , Melanoma , Panthera , Tigres , Animales , Perros , Tigres/fisiología , Melanoma/diagnóstico , Melanoma/terapia , Melanoma/veterinaria , Animales de Zoológico , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/terapia , Melanoma Cutáneo Maligno
2.
Conserv Biol ; 37(2): e13997, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36047697

RESUMEN

Illegal wildlife trade (IWT) is one of the leading causes of the decline in high-value species. Crime-reduction strategies to counter IWT can have unintended effects, with crime displacement occurring when offenders react to such interventions. Despite the value of understanding how and why displacement occurs for informing conservation strategies, few examples are published. We explored a case of perpetrator replacement following an intervention and drew lessons for conservation strategies for high-value species. Poaching and subsequent trade threaten the Sundarbans tiger (Panthera tigris). Pirate gangs were the dominant poachers from 1980 to 2017, but following an extensive campaign, the Sundarbans was declared pirate free in 2018. We interviewed 280 individuals, including 100 tiger poachers, from 26 administrative unions bordering the Sundarbans and used interviewee responses to compare the poaching situation during and after the pirate era. We analyzed the spatial distribution of tiger poachers among the unions and used crime script analysis of the dominant poacher type to identify intervention. Because pirates opportunistically poached tigers, the government's successful counter-pirate campaign inadvertently removed the dominant tiger poaching type. However, a temporary reduction in poaching was rapidly cancelled out by the emergence of at least 32 specialist tiger-poaching teams. With the risk of extortion and robbery from pirates gone, other groups increased the frequency of opportunistic and targeted tiger poaching. Based on expert interviews, we estimated that 341 tiger poachers of all types are active throughout the unions, with 79% of specialists concentrated in 27% of unions. The highly focused counter-pirate campaign reduced motivations and opportunities for piracy but left intact the opportunity structure and trade connections for tiger poaching, and with insufficient enforcement officers trading has flourished. Interventions targeting opportunities for poaching by specialist tiger poachers include heightened surveillance and reporting mechanisms and alternative livelihood provision to disincentivize poaching.


Aprendizaje a partir de la sustitución del infractor para eliminar las oportunidades de crimen y prevenir la caza furtiva del tigre de Sundarbans Resumen El mercado ilegal de fauna (MIF) es una de las principales causas de la declinación de especies importantes. Las estrategias de reducción de crímenes para contrarrestar el MIF pueden tener efectos no deseados, como el desplazamiento del crimen que ocurre cuando los infractores reaccionan a dichas intervenciones. A pesar de lo valioso que es para las estrategias de conservación entender cómo y por qué ocurre este desplazamiento, se publican pocos ejemplos. Exploramos un caso de sustitución del infractor después de una intervención sacamos lecciones para las estrategias de conservación de especies importantes. La caza furtiva y el mercado subsecuente son una amenaza para el tigre de Sundarbans (Panthera tigris). Los piratas fueron los cazadores dominantes entre 1980 y 2017, pero después de una campaña exhaustiva, el Sundarbans fue declarado libre de piratas en 2018. Entrevistamos a 280 individuos, incluidos 100 cazadores furtivos, de 26 uniones administrativas que rodean al Sundarbans y usamos sus respuestas para comparar la situación de la caza furtiva durante y después de los piratas. Analizamos la distribución espacial de los cazadores furtivos entre las uniones y usamos el análisis de escritura criminal del tipo dominante de cazador para identificar las intervenciones. Ya que los piratas eran cazadores furtivos oportunistas, la campaña exitosa del gobierno para contrarrestarlos eliminó sin saberlo el tipo dominante de caza furtiva. Sin embargo, una reducción temporal de la caza se canceló rápidamente con la emergencia de al menos 32 equipos especialistas en la cacería furtiva de los tigres. Sin el riesgo de la extorsión o robo por parte de los piratas, otros grupos incrementaron la frecuencia de la cacería oportunista y focalizada. Con base en las entrevistas a expertos, estimamos que 341 cazadores de tigres de todos los tipos están activos en las uniones, con 79% de los especialistas concentrados en 27% de las uniones. La campaña focalizada anti-piratas redujo las motivaciones y oportunidades de piratería, pero no afectó la estructura de oportunidades y conexiones mercantiles de la cacería furtiva de tigres, lo cual, sumado a la falta de suficientes agentes policiales, ha aumentado el mercado. Las intervenciones enfocadas en las oportunidades de cacería de los cazadores especialistas incluyen una mayor vigilancia y mecanismos de reporte y el suministro de sustentos alternativos para desalentar la cacería furtiva.


Asunto(s)
Conservación de los Recursos Naturales , Tigres , Humanos , Animales , Tigres/fisiología , Crimen/prevención & control , Comercio de Vida Silvestre
3.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34518374

RESUMEN

Most endangered species exist today in small populations, many of which are isolated. Evolution in such populations is largely governed by genetic drift. Empirical evidence for drift affecting striking phenotypes based on substantial genetic data are rare. Approximately 37% of tigers (Panthera tigris) in the Similipal Tiger Reserve (in eastern India) are pseudomelanistic, characterized by wide, merged stripes. Camera trap data across the tiger range revealed the presence of pseudomelanistic tigers only in Similipal. We investigated the genetic basis for pseudomelanism and examined the role of drift in driving this phenotype's frequency. Whole-genome data and pedigree-based association analyses from captive tigers revealed that pseudomelanism cosegregates with a conserved and functionally important coding alteration in Transmembrane Aminopeptidase Q (Taqpep), a gene responsible for similar traits in other felid species. Noninvasive sampling of tigers revealed a high frequency of the Taqpep p.H454Y mutation in Similipal (12 individuals, allele frequency = 0.58) and absence from all other tiger populations (395 individuals). Population genetic analyses confirmed few (minimal number) tigers in Similipal, and its genetic isolation, with poor geneflow. Pairwise FST (0.33) at the mutation site was high but not an outlier. Similipal tigers had low diversity at 81 single nucleotide polymorphisms (mean heterozygosity = 0.28, SD = 0.27). Simulations were consistent with founding events and drift as possible drivers for the observed stark difference of allele frequency. Our results highlight the role of stochastic processes in the evolution of rare phenotypes. We highlight an unusual evolutionary trajectory in a small and isolated population of an endangered species.


Asunto(s)
Evolución Biológica , Flujo Genético , Variación Genética , Genética de Población , Melanosis/genética , Fenotipo , Tigres/fisiología , Secuencia de Aminoácidos , Animales , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Genoma , Genotipo , India , Repeticiones de Microsatélite , Homología de Secuencia , Tigres/genética
4.
Zoo Biol ; 40(4): 320-329, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33861886

RESUMEN

A fifth of all known species are currently classified as threatened in the wild: the rate of biodiversity loss is rapid, continuous, and mostly due to anthropogenic activities. To slow down this decline, the accurate estimation of demographic parameters for threatened species is critical. With this aim, zoo institutions play an important role, giving access to data on zoo-housed animals, which aids researchers working on species life-history traits and intrinsic factors influencing the fitness of both sexes, such as age. While tigers (Panthera tigris) are particularly threatened in their natural environment, few of their demographic parameters have been determined because of their solitary and elusive nature as well as low population density. Using individual-based information for more than 9200 tigers (from 1938 to 2018) recorded in the International Tiger Studbook 2018, we aimed to determine sub-species and sex-specific variability of survival and reproductive parameters with age. No significant sex-difference in actuarial senescence (i.e., decline of survival probabilities with age) was observed but males tended to have a higher juvenile mortality and a faster senescence than females. Reproductive senescence (i.e., decline of reproductive parameters with age) was more pronounced in females than males. Moreover, we observed sub-species-specific variation in mortality and reproductive patterns, pointing out the necessity to consider them independently for conservation goals. Our findings can provide meaningful improvements to the husbandry of zoo-housed tigers, emphasizing the importance of adult breeding females of 7-9 years-old to control zoo-housed population size, but also providing accurate demographic estimates, crucial to set up effective conservation plans.


Asunto(s)
Envejecimiento , Animales de Zoológico , Conservación de los Recursos Naturales , Reproducción/fisiología , Tigres/genética , Tigres/fisiología , Animales , Especies en Peligro de Extinción , Femenino , Masculino , Especificidad de la Especie
5.
Gen Comp Endocrinol ; 308: 113783, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33862051

RESUMEN

Over the last century, wild tiger (Panthera tigris) numbers have declined from over 100 000 individuals to fewer than 4 000, with animals now confined to less than 5% of their historic range due to habitat loss, persecution, inadequate management, and poaching. In contrast, 15 000-20 000 tigers are estimated to be housed in captivity, experiencing conditions vastly different than their wild counterparts. A total of 280 tigers are currently held at 44 different facilities within South Africa, including zoos, semi-captive 're-wilded' populations, and pets; these animals provide a unique opportunity to measure the impact of extrinsic factors, found in exotic habitats, on the adrenocortical activity of tigers. By monitoring and comparing stress-related faecal glucocorticoid metabolite (fGCM) concentrations of tigers housed at different locations, and free ranging tigers in natural tiger reserves, this project aimed to get a better understanding of the impact of extrinsic factors on adrenocortical function as a measure of stress. The results of this study showed no significant difference in fGCM concentrations between captive, re-wilded, and free-ranging tigers with the exception of one site. Furthermore, factors such as sex and season were not significant drivers of fGCM concentrations. One study group had elevated fGCM concentrations, showing population variation in the stress response. This indicates that populations are able to cope with exotic environments, however, as population-specific differences in the stress response exist, we suggest management protocols be created for each population. This study offered the unique opportunity to see how well tigers are faring outside of their native range and if having re-wilded tigers in exotic locations is a potential welfare-acceptable management option for tiger conservation globally.


Asunto(s)
Tigres , Animales , Conservación de los Recursos Naturales/métodos , Ecosistema , Glucocorticoides , Sudáfrica , Tigres/fisiología
6.
Zoo Biol ; 40(4): 306-319, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33724521

RESUMEN

Tigers (Panthera tigris spp.) are endangered in the wild; ensuring sustainable insurance populations requires careful planning within zoological collections. In captive situations, contraceptives are often used to control breeding and ensure genetically viable populations that contain manageable numbers of animals; reversible contraceptives are ideal because they offer flexibility for breeding management. Historically, synthetic progestins, such as melengestrol acetate implants, were used in female tigers, but these are associated with an increased risk of reproductive pathology and subsequent infertility. Recent management advice to ex-situ collections has been to transition to the use of gonadotropin-releasing hormone agonists, such as deslorelin acetate implants, which do not appear to have a similar risk of reproductive pathology but are associated with highly variable reversal times in exotic felids. Using data from 917 contraceptive records in female tigers captured by the Association of Zoos and Aquariums Reproductive Management Center and the European Association of Zoos and Aquaria Reproductive Management Group's joint Contraception Database and from supplementary surveys, this study reviews the changing use of contraceptives in captive female tigers. The aim was to describe the historical and current use of contraceptives and provide a comprehensive assessment on the use of deslorelin implants, including data on product protocols, efficacy, pathology, and reversibility. This study determined that current dose, frequency, reversibility, and anatomical placement sites of deslorelin implants are highly variable, indicating that specific, readily available, unified, evidence-based recommendations on the use of deslorelin would be useful for future contraceptive use in managed tiger populations.


Asunto(s)
Animales de Zoológico , Anticonceptivos Femeninos/farmacología , Tigres/fisiología , Pamoato de Triptorelina/análogos & derivados , Animales , Femenino , Estudios Retrospectivos , Pamoato de Triptorelina/administración & dosificación , Pamoato de Triptorelina/farmacología
7.
Sci Rep ; 10(1): 11473, 2020 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-32651414

RESUMEN

Tigers and leopards have experienced considerable declines in their population due to habitat loss and fragmentation across their historical ranges. Multi-scale habitat suitability models (HSM) can inform forest managers to aim their conservation efforts at increasing the suitable habitat for tigers by providing information regarding the scale-dependent habitat-species relationships. However the current gap of knowledge about ecological relationships driving species distribution reduces the applicability of traditional and classical statistical approaches such as generalized linear models (GLMs), or occupancy surveys to produce accurate predictive maps. This study investigates the multi-scale habitat relationships of tigers and leopards and the impacts of future climate change on their distribution using a machine-learning algorithm random forest (RF). The recent advancements in the machine-learning algorithms provide a powerful tool for building accurate predictive models of species distribution and their habitat relationships even when little ecological knowledge is available about the species. We collected species occurrence data using camera traps and indirect evidence of animal presences (scats) in the field over 2 years of rigorous sampling and used a machine-learning algorithm random forest (RF) to predict the habitat suitability maps of tiger and leopard under current and future climatic scenarios. We developed niche overlap models based on the recently developed statistical approaches to assess the patterns of niche similarity between tigers and leopards. Tiger and leopard utilized habitat resources at the broadest spatial scales (28,000 m). Our model predicted a 23% loss in the suitable habitat of tigers under the RCP 8.5 Scenario (2050). Our study of multi-scale habitat suitability modeling provides valuable information on the species habitat relationships in disturbed and human-dominated landscapes concerning two large felid species of conservation importance. These areas may act as refugee habitats for large carnivores in the future and thus should be the focus of conservation importance. This study may also provide a methodological framework for similar multi-scale and multi-species monitoring programs using robust and more accurate machine learning algorithms such as random forest.


Asunto(s)
Conservación de los Recursos Naturales , Ecología , Panthera/fisiología , Tigres/fisiología , Algoritmos , Animales , Gatos , Ecosistema , Humanos , Modelos Biológicos
8.
J Zoo Wildl Med ; 51(3): 652-656, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33480540

RESUMEN

Spontaneous ovulation has been identified in several wild felid species and domestic cats previously thought to undergo only induced ovulation. Two studies have assessed ovulation patterns in tigers (Panthera tigris) and have not found evidence of spontaneous ovulation in this species. However, uterine pathology typically associated with prolonged progesterone exposure has been identified in unbred tigers, suggesting spontaneous ovulation occurs. Ovaries from 47 tigers were reviewed with histologic examination. The presence or lack of active corpora lutea was documented and compared with social housing conditions for each animal. Social housing categories were as follows: female housed alone, female housed with other females, and female housed with at least one male. Active corpora lutea were identified in 66% (10/15) of females housed alone, 85% (6/7) of females housed with other females, and 58% of females housed with a male. A chi-squared test found the presence of active corpora lutea was independent of social housing condition. These results offer strong evidence of spontaneous ovulation in tigers. This finding suggests that a luteal control protocol with an early follicular inhibition agent may improve assisted reproduction efforts and supports spaying nonreproductive or postreproductive female tigers to reduce the rate of uterine infections.


Asunto(s)
Ovario/anatomía & histología , Ovulación , Tigres/fisiología , Animales , Animales de Zoológico/anatomía & histología , Animales de Zoológico/fisiología , Femenino , Vivienda para Animales , Ovario/fisiología , Tigres/anatomía & histología
9.
Sensors (Basel) ; 19(24)2019 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-31835550

RESUMEN

Monitoring the cardiopulmonary signal of animals is a challenge for veterinarians in conditions when contact with a conscious animal is inconvenient, difficult, damaging, distressing or dangerous to personnel or the animal subject. In this pilot study, we demonstrate a computer vision-based system and use examples of exotic, untamed species to demonstrate this means to extract the cardiopulmonary signal. Subject animals included the following species: Giant panda (Ailuropoda melanoleuca), African lions (Panthera leo), Sumatran tiger (Panthera tigris sumatrae), koala (Phascolarctos cinereus), red kangaroo (Macropus rufus), alpaca (Vicugna pacos), little blue penguin (Eudyptula minor), Sumatran orangutan (Pongo abelii) and Hamadryas baboon (Papio hamadryas). The study was done without need for restriction, fixation, contact or disruption of the daily routine of the subjects. The pilot system extracts the signal from the abdominal-thoracic region, where cardiopulmonary activity is most likely to be visible using image sequences captured by a digital camera. The results show motion on the body surface of the subjects that is characteristic of cardiopulmonary activity and is likely to be useful to estimate physiological parameters (pulse rate and breathing rate) of animals without any physical contact. The results of the study suggest that a fully controlled study against conventional physiological monitoring equipment is ethically warranted, which may lead to a novel approach to non-contact physiological monitoring and remotely sensed health assessment of animals. The method shows promise for applications in veterinary practice, conservation and game management, animal welfare and zoological and behavioral studies.


Asunto(s)
Abdomen/fisiología , Fenómenos Fisiológicos Cardiovasculares , Monitoreo Fisiológico , Grabación en Video/métodos , Abdomen/diagnóstico por imagen , Animales , Camélidos del Nuevo Mundo/fisiología , Sistema Cardiovascular/diagnóstico por imagen , Hospitales Veterinarios , Humanos , Leones/fisiología , Macropodidae/fisiología , Papio/fisiología , Phascolarctidae/fisiología , Proyectos Piloto , Spheniscidae/fisiología , Tigres/fisiología , Ursidae/fisiología
10.
PLoS One ; 14(7): e0217540, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31260478

RESUMEN

Worldwide, roads are a main driver of deforestation and degradation as they increase forest access along the forest edge. In many tropical areas, unofficial roads go unreported and unrecorded, resulting in inaccurate estimates of intact forested areas. This is the case in central Sumatra, which boasts populations of critically endangered Sumatran elephants (Elephas maximus sumatrensis), tigers (Panthera tigris sumatrae) and other endemic flora and fauna that make the area globally unique. However, maps do not reflect the reality of forest loss in the area. Here we present new maps from 2002 and 2016 of digitized and ground-truthed roads in one of Sumatra's unique lowland tropical protected areas, Tesso Nilo National Park. Using our newly created roads dataset, we examine the distribution of forest with respect to distance to roads. Our data show >2,400 km of roads within the national park in 2016 -nearly a 10-fold increase from roads known in 2002. Most forest (82-99%) within Tesso Nilo falls within 100 m, 500 m, and 1000 m of road edges. Length of road increased 157% and road density increased from 1.06 km/km2 to 2.63 km/km2 from 2002-2016. Our results suggest that this endemic ecosystem is facing substantial threat from roads and their associated impacts. Without swift management action, such as road closures and increased enforcements by park management, this ecosystem, and its endemic wildlife, could be lost. It is imperative that protected areas worldwide more rigorously consider roads and road effects on ecosystem fragmentation in their conservation plans.


Asunto(s)
Conservación de los Recursos Naturales/estadística & datos numéricos , Especies en Peligro de Extinción/tendencias , Bosques , Transportes/ética , Animales , Aves/fisiología , Ecosistema , Elefantes/fisiología , Indonesia , Tigres/fisiología , Transportes/estadística & datos numéricos
11.
PLoS One ; 14(4): e0214447, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30969977

RESUMEN

Application of different antibodies and extraction methods results in a wide range of steroid metabolite concentrations obtained during noninvasive hormones monitoring. It makes regional comparisons of steroid concentration very difficult. We compared three methods for extraction of glucocorticoids metabolites in tiger feces to examine correct stress level in Bengal and Amur tigers in India and Russia respectively. The results obtained with three different extraction methods correlate with each other positively and significantly. The highest concentration of fecal glucocorticoids metabolites (FGCM) was found after the extraction of wet feces samples with 90% methanol. The level of FGCM was significantly higher in Bengal tigers in India than in Amur tigers in Russian Far East. The reasons might be related to tigers' density or anthropogenic pressure.


Asunto(s)
Ecosistema , Heces/química , Glucocorticoides/análisis , Estrés Fisiológico , Tigres/fisiología , Animales , Geografía , India , Federación de Rusia , Temperatura
12.
Sci Total Environ ; 663: 830-840, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30738263

RESUMEN

The Sundarbans, in southern coastal Bangladesh, is the world's largest surviving mangrove habitat and the last stronghold of tiger adapted to living in a mangrove ecosystem. Using MaxEnt (maximum entropy modeling), current distribution data, land-use/land cover and bioclimatic variables, we modeled the likely future distribution of the globally endangered Bengal tiger (Panthera tigris tigris) in the Bangladesh Sundarbans. We used two climatic scenarios (i.e., RCP6.0 and RCP8.5) developed by the Intergovernmental Panel on Climate Change (IPCC) to provide projections of suitable habitats of Bengal tigers in 2050 and 2070. We also combined projected sea-level rise for the area in our models of future species distributions. Our results suggest that there will be a dramatic decline in suitable Bengal tiger habitats in the Bangladesh Sundarbans. Other than various aspects of local climate, sea-level rise is projected to have a substantial negative impact on Bengal tiger habitats in this low-lying area. Our model predicts that due to the combined effect of climate change and sea-level rise, there will be no suitable Bengal tiger habitat remaining in the Sundarbans by 2070. Enhancing terrestrial protected area coverage, regular monitoring, law enforcement, awareness-building among local residents among the key strategies needed to ensure long-term survival and conservation of the Bengal tiger in the Bangladesh Sundarbans.


Asunto(s)
Distribución Animal , Cambio Climático , Ecosistema , Especies en Peligro de Extinción , Tigres/fisiología , Animales , Bangladesh , Océanos y Mares , Movimientos del Agua , Humedales
13.
J Zoo Wildl Med ; 49(4): 875-880, 2018 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-30592938

RESUMEN

Eight adult tigers ( Panthera tigris) underwent a complete echocardiographic examination following sedation with medetomidine, midazolam, and induction of general anesthesia using ketamine and isoflurane (phase 1). Atipamezole was used to antagonize medetomidine (phase 2) and a second echocardiographic examination was performed. Physiologic tricuspid and pulmonic regurgitations were common findings in the sample population and one tiger was excluded from final analyses due to the finding of a ventricular septal defect. Measurements and mean arterial pressure were assessed for statistically significant differences between the two examination phases as well as gender and weight. There was a statistically significant difference between interventricular septum thickness at end systole, ejection fraction, and mean arterial pressure between anesthetic phases while fractional shortening and left ventricular internal dimension at end-systole approached, but did not reach, statistical significance between phases. Weight was found to be a statistically significant predictor of stroke volume and left ventricular internal dimension at end-diastole. The echocardiographic measurements obtained during this study can be used as guidelines for future examinations in adult tigers. The effects of medetomidine on these measurements and systolic function should be taken into account when performing echocardiograms and monitoring anesthetic events.


Asunto(s)
Anestesia General/veterinaria , Presión Sanguínea/efectos de los fármacos , Ecocardiografía/veterinaria , Hipnóticos y Sedantes/antagonistas & inhibidores , Imidazoles/administración & dosificación , Medetomidina/antagonistas & inhibidores , Tigres/fisiología , Anestesia General/métodos , Animales , Femenino , Hipnóticos y Sedantes/administración & dosificación , Masculino , Medetomidina/administración & dosificación
14.
PLoS One ; 13(11): e0201447, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30427846

RESUMEN

Religious beliefs and spiritual connections to biodiversity have the potential to reduce animosity towards wildlife that might otherwise present a real or perceived threat to local people. Understanding this social dynamic can therefore be important for formulating locally-appropriate species-specific conservation strategies. Using semi-structured interviews which incorporated human-tiger conflict scenarios, we investigated how beliefs towards tigers varied between ethnic groups living around a large protected area that is home to the largest tiger population in Sumatra. We gathered this information to determine the degree to which cultural tolerance may contribute to the survival of the tiger in the Kerinci Seblat landscape, Indonesia. From 154 interviewees, 133 respondents came from three main ethnic groups, Minangkabau, Kerincinese and Melayu. The majority (73.5%) of Minangkabau interviewees cited that their ethnic group had customary laws regarding tigers, as did 52% of Melayu and 44% of Kerincinese. Irrespective of ethnicity, most participants did not perceive there to be a connection between Islam and tigers. All participants acknowledged the existence of zoological tigers and two groups (Minangkabau and Kerincinese) held a strong common belief that different types of spirit tigers also existed. From presenting different human-tiger conflict scenarios, with varying levels of severity towards livestock or human life, an unprovoked tiger attack in the village elicited the most calls for the tiger to be killed. Yet, if a village or family member was killed by a tiger whilst hunting in the forest then most respondents across all ethnic groups said to do nothing. The frequency of this response increased if a tiger killed someone in the village who had committed adultery, reflecting beliefs associated with the role of the tiger as an enforcer of moral rule. Our study highlights the importance of consulting with local communities who live in close proximity to large and potentially dangerous carnivores when developing conflict mitigation strategies, which hitherto has not been the case in Sumatra.


Asunto(s)
Conservación de los Recursos Naturales , Cultura , Especies en Peligro de Extinción , Tigres , Animales , Animales Salvajes/fisiología , Conservación de los Recursos Naturales/métodos , Ecosistema , Bosques , Humanos , Indonesia , Religión , Población Rural , Tigres/fisiología
15.
Am J Vet Res ; 79(8): 845-851, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30058850

RESUMEN

OBJECTIVE To investigate use of the plethysmographic variability index (PVI) and perfusion index (PI) for evaluating changes in arterial blood pressure in anesthetized tigers (Panthera tigris). ANIMALS 8 adult tigers. PROCEDURES Each tiger was anesthetized once with a combination of ketamine, midazolam, medetomidine, and isoflurane. Anesthetic monitoring included assessment of PI, PVI, direct blood pressure measurements, anesthetic gas concentrations, esophageal temperature, and results of capnography and ECG. Mean arterial blood pressure (MAP) was maintained for at least 20 minutes at each of the following blood pressure conditions: hypotensive (MAP = 50 ± 5 mm Hg), normotensive (MAP = 70 ± 5 mm Hg), and hypertensive (MAP = 90 ± 5 mm Hg). Arterial blood gas analysis was performed at the beginning of anesthesia and at each blood pressure condition. RESULTS Mean ± SD PI values were 1.82 ± 2.38%, 1.17 ± 0.77%, and 1.71 ± 1.51% and mean PVI values were 16.00 ± 5.07%, 10.44 ± 3.55%, and 8.17 ± 3.49% for hypotensive, normotensive, and hypertensive conditions, respectively. The PI values did not differ significantly among blood pressure conditions. The PVI value for the hypotensive condition differed significantly from values for the normotensive and hypertensive conditions. The PVI values were significantly correlated with MAP (r = -0.657). The OR of hypotension to nonhypotension for PVI values ≥ 18% was 43.6. CONCLUSIONS AND CLINICAL RELEVANCE PVI was a clinically applicable variable determined by use of noninvasive methods in anesthetized tigers. Values of PVI ≥ 18% may indicate hypotension.


Asunto(s)
Anestésicos por Inhalación/farmacología , Determinación de la Presión Sanguínea/normas , Determinación de la Presión Sanguínea/veterinaria , Presión Sanguínea/efectos de los fármacos , Tigres/fisiología , Anestesia/métodos , Animales , Femenino , Isoflurano/farmacología , Ketamina/farmacología , Masculino , Medetomidina/farmacología , Midazolam/farmacología , Perfusión
16.
PLoS One ; 13(5): e0195612, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29795557

RESUMEN

India with estimated more than 2000 tigers (across 18 states) accounts for more than half of the remaining tigers across its range countries. Long-term conservation requires measures to protect the large carnivores and its prey base beyond the Protect Areas. The Corbett Tiger Reserve (CTR) and adjoining forest divisions with high density of tigers play a crucial role in conservation of tiger in Uttarakhand state as well as the Terai-Arc Landscape. However, CTR is surrounded with multiple-use forest (forest divisions), agriculture land, human habitation, townships and developmental projects. The movement of large carnivores and other wildlife through such habitats adds to the chances of human-wildlife conflict. The aim of the current study was to understand the patterns of livestock depredation by tigers and leopards in and around CTR. We examined a total of 8365 incidents of livestock depredation between 2006 and 2015 with tigers killing more livestock in a year (573.3±41.2) than leopards (263.2±9.9). Geographically, in north zone of CTR leopards were the major livestock predator (166.6±11), whereas tigers (547.7±40.1) in south zone. Examination of livestock kills indicated cows (75%) as the main victim, followed by buffaloes and other species. Analysis revealed that the livestock depredation by tigers varied significantly among seasons in south zone but not in north zone. However, such an explicit seasonal variation was not observed for leopards in north and south zone of CTR. Hotspots of livestock predation were identified around CTR. Addressing a conflict situation in a time-bound manner, timely disbursement of ex-gratia payment, involving locals at various tourism related activities and consistent rapport building initiatives are required to mitigate the human-wildlife conflict.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Ganado , Panthera/fisiología , Conducta Predatoria , Tigres/fisiología , Tigres/psicología , Animales , Bovinos , Femenino , Humanos , Masculino
17.
Integr Zool ; 13(5): 595-603, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29722132

RESUMEN

A small, isolated Amur tiger population ranges across the southwest Primorskii Krai region in Russia and Hunchun region in China. Many individuals, with "dual nationality," cross the border frequently. Formulating effective conservation strategies requires a clear understanding of tiger food requirements in both countries. While the diets of tigers ranging in Russia is clearly understood, little is known of the tigers' feeding habits in China.. We used scat analysis combined with data on the abundance of 4 prey species to examine Amur tiger diet and prey preferences in Hunchun. We examined 53 tiger scat samples from 2011 to 2016 and found that tigers preyed on 12 species (11 species in winter), 4 of which were domestic animals with 33.58% biomass contribution; this was the first record of Amur tigers eating lynx in this area. Tigers showed a strong preference for wild boar (Jacobs index: +0.849), which were also the most frequently consumed prey, and a strong avoidance of roe deer (Jacobs index: -0.693). On the Russian side, domestic animals (just dog) were rarely found in tiger scat, and tigers did not show strong avoidance of roe deer, but of sika deer. We also found red deer footprints during winter surveys and that tigers ate red deer on the Chinese side, while there was no record of red deer feeding on the Russian side. Reducing or eliminating human disturbance, such as grazing, is essential to recovering tiger prey and habitat in this area and the Sino-Russian joint ungulate annual survey is indispensable for prey estimates of this small, isolated Amur tiger population.


Asunto(s)
Distribución Animal , Conducta Alimentaria , Conducta Predatoria/fisiología , Tigres/fisiología , Animales , China , Ecosistema , Heces , Federación de Rusia
18.
Nat Commun ; 8(1): 1783, 2017 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-29208916

RESUMEN

The continuing development of improved capture-recapture (CR) modeling techniques used to study apex predators has also limited robust temporal and cross-site analyses due to different methods employed. We develop an approach to standardize older non-spatial CR and newer spatial CR density estimates and examine trends for critically endangered Sumatran tigers (Panthera tigris sumatrae) using a meta-regression of 17 existing densities and new estimates from our own fieldwork. We find that tiger densities were 47% higher in primary versus degraded forests and, unexpectedly, increased 4.9% per yr from 1996 to 2014, likely indicating a recovery from earlier poaching. However, while tiger numbers may have temporarily risen, the total potential island-wide population declined by 16.6% from 2000 to 2012 due to forest loss and degradation and subpopulations are significantly more fragmented. Thus, despite increasing densities in smaller parks, we conclude that there are only two robust populations left with >30 breeding females, indicating Sumatran tigers still face a high risk of extinction unless deforestation can be controlled.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Especies en Peligro de Extinción , Bosques , Tigres/fisiología , Animales , Conservación de los Recursos Naturales/tendencias , Ecosistema , Femenino , Geografía , Malasia , Densidad de Población , Factores de Tiempo
19.
PLoS One ; 12(6): e0177548, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28591175

RESUMEN

The source populations of tigers are mostly confined to protected areas, which are now becoming isolated. A landscape scale conservation strategy should strive to facilitate dispersal and survival of dispersing tigers by managing habitat corridors that enable tigers to traverse the matrix with minimal conflict. We present evidence for tiger dispersal along transboundary protected areas complexes in the Terai Arc Landscape, a priority tiger landscape in Nepal and India, by comparing camera trap data, and through population models applied to the long term camera trap data sets. The former showed that 11 individual tigers used the corridors that connected the transboundary protected areas. The estimated population growth rates using the minimum observed population size in two protected areas in Nepal, Bardia National Park and Suklaphanta National Park showed that the increases were higher than expected from growth rates due to in situ reproduction alone. These lines of evidence suggests that tigers are recolonizing Nepal's protected areas from India, after a period of population decline, and that the tiger populations in the transboundary protected areas complexes may be maintained as meta-population. Our results demonstrate the importance of adopting a landscape-scale approach to tiger conservation, especially to improve population recovery and long term population persistence.


Asunto(s)
Conservación de los Recursos Naturales , Dinámica Poblacional , Tigres/fisiología , Animales , Ecosistema , India , Modelos Teóricos , Nepal , Densidad de Población
20.
PLoS One ; 12(4): e0174844, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28379997

RESUMEN

Grazing livestock in openly accessible areas is a common practice in the multiple-use forests of India; however, its compatibility with the reintroduction of tigers to these areas requires examination. Here, we investigated the diet of tigers in a livestock-dominated multiple-use buffer zone of the Panna Tiger Reserve, India. We hypothesised that the presence of feral cattle, along with open-access grazing practices in multiple-use forests, would increase the incidence of predation on livestock by tigers, even when wild prey are available. We used generalised linear models to test whether predation of livestock versus wild animals was influenced by (1) the sex and age class of tigers, (2) season, and (3) the distance of prey from the core-zone boundary of the reserve. Overall, sub-adult tigers and male tigers killed more livestock than wild prey, even when wild prey was available. In the winter and rainy seasons livestock were killed in higher numbers in the buffer zone than in summers, this may be because of the seasonally changing livestock herding patterns in the area. Further, with increasing distance from the core-zone boundary, all tigers killed more livestock, possibly because livestock were more easily accessible than wild prey. Our results show that open-access and unregulated livestock grazing is not currently compatible with large carnivore conservation in the same landscape. Such practices will lead to an increase in negative tiger-human-livestock interactions. In conclusion, we suggest the need to encourage locals to corral valuable cattle, leaving feral/unwanted livestock for tigers. This simple strategy would benefit both local inhabitants and tiger conservation in the multiple-use forests of India.


Asunto(s)
Tigres/fisiología , Crianza de Animales Domésticos , Animales , Animales Salvajes , Conservación de los Recursos Naturales/métodos , Dieta/estadística & datos numéricos , Especies en Peligro de Extinción , Femenino , India , Ganado , Masculino , Conducta Predatoria , Tigres/psicología
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