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1.
J Environ Manage ; 293: 112870, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34052615

RESUMEN

In the Brazilian Pantanal, wildfire occurrence has increased, reaching record highs of over 40,000 km2 in 2020. Smoke from wildfires worsened the situation of isolated, as well as urban communities, already under an increasing toll of COVID-19. Here we review the impacts and the possible causes of the 2020 mega-fires and recommend improvements for public policies and fire management in this wetland. We calculated the amount of area burnt annually since 2003 and describe patterns in precipitation and water level measurements of the Paraguay River. Our analyses revealed that the 2020 wildfires were historically unprecedented, as 43% of the area (over 17,200 km2) had not been burnt previously in the last two decades. The extent of area affected in 2020 represents a 376% increase compared to the annual average of the area burnt annually in the last two decades, double than the value in 2019. Potential factors responsible for this increase are (i) severe drought decreased water levels, (ii) the fire corridor was located in the Paraguay River flood zone, (iii) constraints on firefighters, (iv) insufficient fire prevention strategy and agency budget reductions, and (v) recent landscape changes. Climate and land use change will further increase the frequency of these extreme events. To make fire management more efficient and cost-effective, we recommend the implementation of an Integrated Fire Management program in the Pantanal. Stakeholders should use existing traditional, local ecological, and scientific knowledge to form a collective strategy with clear, achievable, measurable goals, considering the socio-ecological context. Permanent fire brigades, including indigenous members, should conduct year-round fire management. Communities should cooperate to create a collaborative network for wildfire prevention, the location and characteristics (including flammability) of infrastructures should be (re)planned in fire-prone environments considering and managing fire-catalysed transitions, and depending on the severity of wildfires. The 2020 wildfires were tackled in an ad-hoc fashion and prioritisation of areas for urgent financial investment, management, protection, and restoration is necessary to prevent this catastrophe from happening again.


Asunto(s)
COVID-19 , Incendios Forestales , Biodiversidad , Brasil , Bosques , Humanos , Paraguay , SARS-CoV-2 , Humedales
2.
Conserv Biol ; 34(4): 1017-1028, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32362060

RESUMEN

Accurately quantifying species' area requirements is a prerequisite for effective area-based conservation. This typically involves collecting tracking data on species of interest and then conducting home-range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on the previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home-range areas with global positioning system (GPS) locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4000 kg. We then applied block cross-validation to quantify bias in empirical home-range estimates. Area requirements of mammals <10 kg were underestimated by a mean approximately15%, and species weighing approximately100 kg were underestimated by approximately50% on average. Thus, we found area estimation was subject to autocorrelation-induced bias that was worse for large species. Combined with the fact that extinction risk increases as body mass increases, the allometric scaling of bias we observed suggests the most threatened species are also likely to be those with the least accurate home-range estimates. As a correction, we tested whether data thinning or autocorrelation-informed home-range estimation minimized the scaling effect of autocorrelation on area estimates. Data thinning required an approximately93% data loss to achieve statistical independence with 95% confidence and was, therefore, not a viable solution. In contrast, autocorrelation-informed home-range estimation resulted in consistently accurate estimates irrespective of mass. When relating body mass to home range size, we detected that correcting for autocorrelation resulted in a scaling exponent significantly >1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum.


Efectos del Tamaño Corporal sobre la Estimación de los Requerimientos de Área de Mamíferos Resumen La cuantificación precisa de los requerimientos de área de una especie es un prerrequisito para que la conservación basada en áreas sea efectiva. Esto comúnmente implica la recolección de datos de rastreo de la especie de interés para después realizar análisis de la distribución local. De manera problemática, la autocorrelación en los datos de rastreo puede resultar en una subestimación grave de las necesidades de espacio. Con base en trabajos previos, formulamos una hipótesis en la que supusimos que la magnitud de la subestimación varía con la masa corporal, una relación que podría tener implicaciones serias para la conservación. Para probar esta hipótesis en mamíferos terrestres, estimamos las áreas de distribución local con las ubicaciones en GPS de 757 individuos de 61 especies de mamíferos distribuidas mundialmente con una masa corporal entre 0.4 y 4,000 kg. Después aplicamos una validación cruzada en bloque para cuantificar el sesgo en estimaciones empíricas de la distribución local. Los requerimientos de área de los mamíferos <10 kg fueron subestimados por una media ∼15% y las especies con una masa ∼100 kg fueron subestimadas en ∼50% en promedio. Por lo tanto, encontramos que la estimación del área estaba sujeta al sesgo inducido por la autocorrelación, el cual era peor para las especies de talla grande. En combinación con el hecho de que el riesgo de extinción incrementa conforme aumenta la masa corporal, el escalamiento alométrico del sesgo que observamos sugiere que la mayoría de las especies amenazadas también tienen la probabilidad de ser aquellas especies con las estimaciones de distribución local menos acertadas. Como corrección, probamos si la reducción de datos o la estimación de la distribución local informada por la autocorrelación minimizan el efecto de escalamiento que tiene la autocorrelación sobre las estimaciones de área. La reducción de datos requirió una pérdida de datos del ∼93% para lograr la independencia estadística con un 95% de confianza y por lo tanto no fue una solución viable. Al contrario, la estimación de la distribución local informada por la autocorrelación resultó en estimaciones constantemente precisas sin importar la masa corporal. Cuando relacionamos la masa corporal con el tamaño de la distribución local, detectamos que la corrección de la autocorrelación resultó en un exponente de escalamiento significativamente >1, lo que significa que el escalamiento de la relación cambió sustancialmente en el extremo superior del espectro de la masa corporal.


Asunto(s)
Conservación de los Recursos Naturales , Mamíferos , Animales , Tamaño Corporal , Especies en Peligro de Extinción , Fenómenos de Retorno al Lugar Habitual , Humanos
4.
Ecology ; 99(2): 498, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29399824

RESUMEN

Measures of traits are the basis of functional biological diversity. Numerous works consider mean species-level measures of traits while ignoring individual variance within species. However, there is a large amount of variation within species and it is increasingly apparent that it is important to consider trait variation not only between species, but also within species. Mammals are an interesting group for investigating trait-based approaches because they play diverse and important ecological functions (e.g., pollination, seed dispersal, predation, grazing) that are correlated with functional traits. Here we compile a data set comprising morphological and life history information of 279 mammal species from 39,850 individuals of 388 populations ranging from -5.83 to -29.75 decimal degrees of latitude and -34.82 to -56.73 decimal degrees of longitude in the Atlantic forest of South America. We present trait information from 16,840 individuals of 181 species of non-volant mammals (Rodentia, Didelphimorphia, Carnivora, Primates, Cingulata, Artiodactyla, Pilosa, Lagomorpha, Perissodactyla) and from 23,010 individuals of 98 species of volant mammals (Chiroptera). The traits reported include body mass, age, sex, reproductive stage, as well as the geographic coordinates of sampling for all taxa. Moreover, we gathered information on forearm length for bats and body length and tail length for rodents and marsupials. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

5.
Ecology ; 99(7): 1691, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29961270

RESUMEN

The field of movement ecology has rapidly grown during the last decade, with important advancements in tracking devices and analytical tools that have provided unprecedented insights into where, when, and why species move across a landscape. Although there has been an increasing emphasis on making animal movement data publicly available, there has also been a conspicuous dearth in the availability of such data on large carnivores. Globally, large predators are of conservation concern. However, due to their secretive behavior and low densities, obtaining movement data on apex predators is expensive and logistically challenging. Consequently, the relatively small sample sizes typical of large carnivore movement studies may limit insights into the ecology and behavior of these elusive predators. The aim of this initiative is to make available to the conservation-scientific community a dataset of 134,690 locations of jaguars (Panthera onca) collected from 117 individuals (54 males and 63 females) tracked by GPS technology. Individual jaguars were monitored in five different range countries representing a large portion of the species' distribution. This dataset may be used to answer a variety of ecological questions including but not limited to: improved models of connectivity from local to continental scales; the use of natural or human-modified landscapes by jaguars; movement behavior of jaguars in regions not represented in this dataset; intraspecific interactions; and predator-prey interactions. In making our dataset publicly available, we hope to motivate other research groups to do the same in the near future. Specifically, we aim to help inform a better understanding of jaguar movement ecology with applications towards effective decision making and maximizing long-term conservation efforts for this ecologically important species. There are no costs, copyright, or proprietary restrictions associated with this data set. When using this data set, please cite this article to recognize the effort involved in gathering and collating the data and the willingness of the authors to make it publicly available.


Asunto(s)
Panthera , Animales , Ecología , Femenino , Humanos , Masculino , Movimiento
6.
An Acad Bras Cienc ; 90(2 suppl 1): 2129-2139, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28832728

RESUMEN

The Pantanal is the largest inland wetland in the world and is under increasing anthropogenic threats, including long-term regionally intensive gold mining practices. Gold mining activities are known to cause the release of harmful pollutants such as mercury (Hg) to the surrounding environment. Jaguars (Panthera onca (Linnaeus, 1758)) are apex predators, and therefore show great potential to accumulate Hg by biomagnification. We hypothesize that total Hg content in the fur of jaguars from two sites within the Brazilian Pantanal would be significantly different as a function of distance from active gold mining operations. The Hg content was determined by fluorescence spectrometry. The mean ± SD Hg content in jaguars from the study site influenced by gold mining (SB) was compared to jaguars sampled in the area free of gold mining activities (CA) using a one-way ANOVA. The mean Hg content in jaguars from SB (673.0 ± 916.8 µg g-1) is significantly different from jaguars sampled in CA (29.7 ± 23.3 µg g-1), p = 0.03. The maximum recorded content of Hg was 2,010.4 ± 150.5 µg g-1, highest level ever recorded in a wild animal. The data indicate that Hg is an important threat to jaguars within at-risk regions of the Pantanal.

7.
Sci Rep ; 14(1): 13538, 2024 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866909

RESUMEN

Although considered an evolutionary force responsible for shaping ecosystems and biodiversity, fires' natural cycle is being altered by human activities, increasing the odds of destructive megafire events. Here, we show that forest type modulates the responses of terrestrial mammals, from species to assemblage level, to a catastrophic megafire in the Brazilian Pantanal. We unraveled that mammalian richness was higher 1 year after fire passage compared to a pre-fire condition, which can be attributed to habitat modification caused by wildfires, attracting herbivores and open-area tolerant species. We observed changes in assemblage composition between burned/unburned sites, but no difference in mammalian richness or relative abundance. However, by partitioning the effects of burned area proportion per forest type (monospecific vs. polyspecific), we detected differential responses of mammals at several levels of organization, with pronounced declines in species richness and relative abundance in monospecific forests. Eighty-six percent of the species presented moderate to strong negative effects on their relative abundance, with an overall strong negative effect for the entire assemblage. Wildfires are predicted to be more frequent with climate and land use change, and if events analogous to Pantanal-2020 become recurrent, they might trigger regional beta diversity change, benefitting open-area tolerant species.


Asunto(s)
Biodiversidad , Bosques , Mamíferos , Incendios Forestales , Animales , Brasil , Ecosistema , Incendios
8.
Commun Biol ; 6(1): 132, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36792802

RESUMEN

Jaguars (Panthera onca) exert critical top-down control over large vertebrates across the Neotropics. Yet, this iconic species have been declining due to multiple threats, such as habitat loss and hunting, which are rapidly increasing across the New World tropics. Based on geospatial layers, we extracted socio-environmental variables for 447 protected areas across the Brazilian Amazon to identify those that merit short-term high-priority efforts to maximize jaguar persistence. Data were analyzed using descriptive statistics and comparisons of measures of central tendency. Our results reveal that areas containing the largest jaguar densities and the largest estimated population sizes are precisely among those confronting most anthropogenic threats. Jaguars are threatened in the world's largest tropical forest biome by deforestation associated with anthropogenic fires, and the subsequent establishment of pastures. By contrasting the highest threats with the highest jaguar population sizes in a bivariate plot, we provide a shortlist of the top-10 protected areas that should be prioritized for immediate jaguar conservation efforts and 74 for short-term action. Many of these are located at the deforestation frontier or in important boundaries with neighboring countries (e.g., Peruvian, Colombian and Venezuelan Amazon). The predicament of a safe future for jaguars can only be ensured if protected areas persist and resist downgrading and downsizing due to both external anthropogenic threats and geopolitical pressures (e.g., infrastructure development and frail law enforcement).


Asunto(s)
Conservación de los Recursos Naturales , Panthera , Animales , Conservación de los Recursos Naturales/métodos , Brasil , Ecosistema , Densidad de Población
9.
Gen Comp Endocrinol ; 179(2): 232-40, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22917914

RESUMEN

In this study we measured excreted fecal corticoid metabolites (FCM) in maned wolves (Chrysocyon brachyurus) living within a protected reserve, on farmlands or in a boundary zone between the two habitats, and determined the impacts of season and reproductive status on adrenal activity. Feces were collected within a national park (n=191 samples), a park boundary zone (n=39) and on nearby farmlands (n=27), processed and analyzed by enzyme immunoassay. FCM amounts from samples collected on farmlands were higher (P<0.05) than in those collected inside the reserve and from the boundary zone. In relation to seasonality, FCM were elevated (P<0.05) in spring (September-November) when wolf pairs were raising young. We then divided the samples collected during breeding season (March-August) into cycling females and male/non-cycling females based on fecal progesterone: fecal testosterone ratio. FCM concentrations of the former collected inside the park were higher than (P<0.05) than the latter group. However, there were no differences in FCM levels between the two groups for samples collected in the boundary zone and on farmlands. Furthermore, FCM concentrations of male/non-cycling females samples collected on farmlands were 2- to 5-fold higher (P<0.05) than in counterparts collected inside the park. The consistently high FCM concentrations in samples collected on farmlands indicate that, in addition to seasonality, gender and reproductive status, anthropogenic pressures also contribute to elevating adrenal steroid for individuals living in altered habitat.


Asunto(s)
Corticoesteroides/análisis , Glándulas Suprarrenales/fisiología , Canidae/fisiología , Ecosistema , Heces/química , Agricultura , Animales , Brasil , Conservación de los Recursos Naturales , Femenino , Masculino , Progesterona/metabolismo , Reproducción/fisiología , Estaciones del Año , Testosterona/metabolismo
10.
Zoo Biol ; 31(4): 426-41, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21953790

RESUMEN

Jaguars are threatened with extinction throughout their range. A sustainable captive population can serve as a hedge against extinction, but only if they are healthy and reproduce. Understanding how jaguars respond to stressors may help improve the captive environment and enhance their wellbeing. Thus, our objectives were to: (1) conduct an adrenocorticotrophic hormone (ACTH) challenge to validate a cortisol radioimmunoassay (RIA) for noninvasive monitoring of adrenocortical function in jaguars; (2) investigate the relationship between fecal corticoid (FCM) and androgen metabolite (FAM) concentrations in males during the ACTH challenge; and (3) establish a range of physiological concentrations of FCMs for the proposed protocol. Seven jaguars (3 M, 4 F) received 500 IU/animal of ACTH. Pre- and post-ACTH fecal samples were assayed for corticoid (M and F) and androgen metabolites (M) by RIA. Concentrations of FCMs increased (P80.01) after ACTH injection (pre-ACTH: 0.90 ± 0.12 µg/g dry feces; post-ACTH: 2.55 ± 0.25 µg/g). Considering pre- and post-ACTH samples, FCM concentrations were higher (P80.01) in males (2.15 ± 0.20 µg/g) than in females (1.30 ± 0.20 µg/g), but the magnitude of the response to ACTH was comparable (P>0.05) between genders. After ACTH injection, FAMs increased in two (of 3) males; in one male, FCMs and FAMs were positively correlated (0.60; P80.01). Excretion of FCMs was assessed in 16 jaguars (7 M, 9 F) and found to be highly variable (range, 80.11-1.56 µg/g). In conclusion, this study presents a cortisol RIA for monitoring adrenocortical function in jaguars noninvasively.


Asunto(s)
Pruebas de Función de la Corteza Suprarrenal/métodos , Corteza Suprarrenal/metabolismo , Hormona Adrenocorticotrópica/farmacología , Animales de Zoológico , Monitoreo Fisiológico/métodos , Panthera/metabolismo , Radioinmunoensayo/normas , Corticoesteroides/análisis , Hormona Adrenocorticotrópica/administración & dosificación , Animales , Heces/química , Femenino , Masculino , Radioinmunoensayo/métodos
11.
Ecology ; 103(1): e03543, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34841521

RESUMEN

Energetic subsidies between terrestrial and aquatic ecosystems can strongly influence food webs and population dynamics. Our objective was to study how aquatic subsidies affected jaguar (Panthera onca) diet, sociality, and population density in a seasonally flooded protected area in the Brazilian Pantanal. The diet (n = 138 scats) was dominated by fish (46%) and aquatic reptiles (55%), representing the first jaguar population known to feed extensively on fish and to minimally consume mammals (11%). These aquatic subsidies supported the highest jaguar population density estimate to date (12.4 jaguars/100 km²) derived from camera traps (8,065 trap nights) and GPS collars (n = 13). Contrary to their mostly solitary behavior elsewhere, we documented social interactions previously unobserved between same-sex adults including cooperative fishing, co-traveling, and play. Our study demonstrates that aquatic subsidies, frequently described in omnivores, can also transform the ecology and behavior of obligate carnivores.


Asunto(s)
Ecosistema , Panthera , Animales , Ecología , Densidad de Población , Conducta Predatoria , Brasil
12.
Commun Biol ; 5(1): 1028, 2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36229543

RESUMEN

The Pantanal wetland harbours the second largest population of jaguars in the world. Alongside climate and land-use changes, the recent mega-fires in the Pantanal may pose a threat to the jaguars' long-term survival. To put these growing threats into perspective, we addressed the reach and intensity of fires that have affected jaguar conservation in the Pantanal ecoregion over the last 16 years. The 2020 fires were the most severe in the annual series, burned 31% of the Pantanal and affected 45% of the estimated jaguar population (87% of these in Brazil); 79% of the home range areas, and 54% of the protected areas within home ranges. Fires consumed core habitats and injured several jaguars, the Pantanal's apex predator. Displacement, hunger, dehydration, territorial defence, and lower fecundity are among the impacts that may affect the abundance of the species. These impacts are likely to affect other less mobile species and, therefore, the ecological stability of the region. A solution to prevent the recurrence of mega-fires lies in combating the anthropogenic causes that intensify drought conditions, such as implementing actions to protect springs, increasing the number and area of protected areas, regulating fire use, and allocating fire brigades before dry seasons.


Asunto(s)
Panthera , Incendios Forestales , Animales , Ecosistema , Estaciones del Año , Humedales
13.
PLoS One ; 16(2): e0246233, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33539384

RESUMEN

Animal movement data are widely collected with devices such as sensors and collars, increasing the ability of researchers to monitor animal movement and providing information about animal behavioral patterns. Animal behavior is used as a basis for understanding the relationship between animals and the environment and for guiding decision-making by researchers and public agencies about environmental preservation and conservation actions. Animal movement and behavior are widely studied with a focus on identifying behavioral patterns, such as, animal group formation, the distance between animals and their home range. However, we observed a lack of research proposing a unified solution that aggregates resources for analyses of individual animal behavior and of social interactions between animals. The primary scientific contribution of this work is to present a framework that uses trajectory analysis and association rule mining [Jaiswal and Agarwal, 2012] to provide statistical measures of correlation and dependence to determine the relationship level between animals, their social interactions, and their interactions with other environmental factors based on their individual behavior and movement data. We demonstrate the usefulness of the framework by applying it to movement data from jaguars in the Pantanal, Brazil. This allowed us to describe jaguar behavior, social interactions among jaguars and their behavior in different landscapes, thus providing a highly detailed investigation of jaguar movement decisions at the fine scale.


Asunto(s)
Minería de Datos/métodos , Panthera/fisiología , Conducta Social , Algoritmos , Animales , Conducta Animal/fisiología , Brasil , Conservación de los Recursos Naturales , Toma de Decisiones , Femenino , Masculino , Tecnología de Sensores Remotos/instrumentación , Interacción Social
14.
Sci Rep ; 11(1): 23547, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34916541

RESUMEN

Anthropogenic factors have significantly influenced the frequency, duration, and intensity of meteorological drought in many regions of the globe, and the increased frequency of wildfires is among the most visible consequences of human-induced climate change. Despite the fire role in determining biodiversity outcomes in different ecosystems, wildfires can cause negative impacts on wildlife. We conducted ground surveys along line transects to estimate the first-order impact of the 2020 wildfires on vertebrates in the Pantanal wetland, Brazil. We adopted the distance sampling technique to estimate the densities and the number of dead vertebrates in the 39,030 square kilometers affected by fire. Our estimates indicate that at least 16.952 million vertebrates were killed immediately by the fires in the Pantanal, demonstrating the impact of such an event in wet savanna ecosystems. The Pantanal case also reminds us that the cumulative impact of widespread burning would be catastrophic, as fire recurrence may lead to the impoverishment of ecosystems and the disruption of their functioning. To overcome this unsustainable scenario, it is necessary to establish proper biomass fuel management to avoid cumulative impacts caused by fire over biodiversity and ecosystem services.

15.
Curr Biol ; 31(15): 3457-3466.e4, 2021 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-34237270

RESUMEN

Large terrestrial carnivores have undergone some of the largest population declines and range reductions of any species, which is of concern as they can have large effects on ecosystem dynamics and function.1-4 The jaguar (Panthera onca) is the apex predator throughout the majority of the Neotropics; however, its distribution has been reduced by >50% and it survives in increasingly isolated populations.5 Consequently, the range-wide management of the jaguar depends upon maintaining core populations connected through multi-national, transboundary cooperation, which requires understanding the movement ecology and space use of jaguars throughout their range.6-8 Using GPS telemetry data for 111 jaguars from 13 ecoregions within the four biomes that constitute the majority of jaguar habitat, we examined the landscape-level environmental and anthropogenic factors related to jaguar home range size and movement parameters. Home range size decreased with increasing net productivity and forest cover and increased with increasing road density. Speed decreased with increasing forest cover with no sexual differences, while males had more directional movements, but tortuosity in movements was not related to any landscape factors. We demonstrated a synergistic relationship between landscape-scale environmental and anthropogenic factors and jaguars' spatial needs, which has applications to the conservation strategy for the species throughout the Neotropics. Using large-scale collaboration, we overcame limitations from small sample sizes typical in large carnivore research to provide a mechanism to evaluate habitat quality for jaguars and an inferential modeling framework adaptable to the conservation of other large terrestrial carnivores.


Asunto(s)
Efectos Antropogénicos , Actividad Motora , Panthera , Conducta Espacial , Animales , Conservación de los Recursos Naturales , Ecología , Ecosistema , Masculino
16.
Conserv Physiol ; 8(1): coaa052, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32577289

RESUMEN

Habitat loss and fragmentation have been leading jaguars to constant conflicts with humans, and as a result, jaguar populations have been declining over the last decades. Captive breeding is often a tool for species conservation, and it is not different for jaguars. However, success is far from optimal due to the lack of basic knowledge about species' reproductive biology. In the present study, we assessed gonadal hormonal profiles of natural oestral cycles and puberty and compared our data to those of other wild felids. We collected faecal samples from two to seven times per week for 18 months from two adults and three pre-pubertal females. We defined baseline levels for progestins and oestrogens in order to estimate oestrous cycle length and age at puberty. We compared our data with 16 other species through generalized linear model, using weight and genus as two explanatory variables. Cycle length was 38.28 ± 2.52 days, ranging from 25 to 44 days, while sexual maturity was attained within 22 months. Due to our analysis of both hormonal and behavioural data, there is a variation between this research from other studies that employed only behavioural observations. Such difference may be caused by the absence of behavioural oestrous at the peri-pubertal period. When compared to wild felids of similar size, puberty and oestral cycle durations of the jaguar females fell within the same range. Our modelling showed that age at maturity was influenced mostly by size and only Leopardus partially explained the observed variation. Conversely, oestral cycle length did not differ among genera or size categories. Our study adds to the body literature in the reproductive endocrinology of wild felids, and because female gametes are more challenging to collect and preserve, a strong understanding on the female reproductive physiology is essential to assisted reproduction and wild population viability assessment.

17.
Ecology ; 101(11): e03128, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32862433

RESUMEN

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data.


Asunto(s)
Canidae , Carnívoros , Mustelidae , Ursidae , Animales , Ecosistema , Humanos
18.
Genetica ; 136(3): 505-12, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19137401

RESUMEN

The elusive nature and endangered status of most carnivore species imply that efficient approaches for their non-invasive sampling are required to allow for genetic and ecological studies. Faecal samples are a major potential source of information, and reliable approaches are needed to foster their application in this field, particularly in areas where few studies have been conducted. A major obstacle to the reliable use of faecal samples is their uncertain species-level identification in the field, an issue that can be addressed with DNA-based assays. In this study we describe a sequence-based approach that efficiently distinguishes jaguar versus puma scats, and that presents several desirable properties: (1) considerably high amplification and sequencing rates; (2) multiple diagnostic sites reliably differentiating the two focal species; (3) high information content that allows for future application in other carnivores; (4) no evidence of amplification of prey DNA; and (5) no evidence of amplification of a nuclear mitochondrial DNA insertion known to occur in the jaguar. We demonstrate the reliability and usefulness of this approach by evaluating 55 field-collected samples from four locations in the highly fragmented Atlantic Forest biome of Brazil and Argentina, and document the presence of one or both of these endangered felids in each of these areas.


Asunto(s)
ADN/genética , Ecología/métodos , Heces/química , Panthera/clasificación , Panthera/genética , Puma/clasificación , Puma/genética , Animales , ADN Mitocondrial/genética , Agricultura Forestal , Haplotipos , Filogenia , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN , América del Sur , Especificidad de la Especie
19.
Virus Res ; 131(1): 33-46, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17889396

RESUMEN

The rabies cases in dogs and wild canids in Northeastern Brazil are a public and animal health problem. This paper describes the identities of the coding region of the N-gene of Rabies virus (RABV) isolated in canids from Northeastern Brazil. The genetic tree generated using the sequence data described here divided the cluster BRAZILAN CANIDS into two subclusters (DOG-RELATED STRAINS and WILD CANID-RELATED STRAINS) with identities greater than those already described. The two subclusters are sub-divided into geographic groups related to the origin of the isolates, suggesting a long-standing ecological coexistence of the sequence types characteristic of the groups. This article also analyzes the 513-nucleotide stretch of the mitochondrial DNA control region of rabies-positive canids from Northeastern Brazil with a view to identifying the main RABV host among them. Among the four species of wild canids found in the region, two (Cerdocyon thous and Pseudalopex vetulus) are frequently associated with rabies. Phylogenetic analysis of sequence data generated from mtDNA suggests that C. thous is the main wild canid host in the region. The results obtained in this study are in concordance with the zoology and ecology of wild canids, and thus, help improve epidemiologic vigilance of rabies and allow a more targeted control of the disease.


Asunto(s)
Antígenos Virales , Canidae/virología , Epidemiología Molecular , Virus de la Rabia/genética , Virus de la Rabia/aislamiento & purificación , Rabia/veterinaria , Animales , Animales Salvajes/virología , Brasil/epidemiología , Genes Virales , Nucleoproteínas/química , Nucleoproteínas/genética , Filogenia , Rabia/epidemiología , Virus de la Rabia/clasificación
20.
Anim Reprod Sci ; 195: 1-7, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29935916

RESUMEN

This study was designed to evaluate the efficiency of medetomidine anesthesia for semen collection through urethral catheter in wild and captive jaguars. Six captive and five wild jaguars were chemically restrained with a combination of medetomidine (0.08-0.1 mg/kg) and ketamine (5 mg/kg). After medetomidine administration the urethra was catheterized using a urinary tomcat catheter (1 mm diameter × 130 mm length) to collect semen from all animals. By using this technique, we could collect an average of 347.2 µl of semen containing 2,635.2 sperm/ml. Forward progressive motility, sperm progressive motility, and sperm morphology analysis demonstrated that the methodology did not affect sperm quality. Thus, urethral catheterization after medetomidine administration is a practical and efficient method to collect high-quality semen from wild and captive jaguars; this will enable the development of reproductive assisted technologies for jaguars.


Asunto(s)
Animales Salvajes , Animales de Zoológico , Panthera/fisiología , Análisis de Semen/veterinaria , Cateterismo Urinario/veterinaria , Animales , Hipnóticos y Sedantes/farmacología , Masculino , Medetomidina/farmacología , Semen/fisiología
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