RESUMO
Montane cloud forests are highly threatened ecosystems that are vulnerable to climate change. These complex habitats harbor many species that suffer the negative consequences of this global phenomenon, such as shifts in their distribution and habitat use. The Central American clouded oncilla (Leopardus pardinoides oncilla) is the smallest and most endangered wild cat in Mesoamerica and is primarily reported in cloud forests throughout its distribution. The species is poorly understood, with no studies conducted in Central America assessing its habitat preferences. To bridge this knowledge gap, we sampled two mountain ranges in Costa Rica with camera traps and conducted an occupancy analysis to understand the anthropogenic and environmental features that influence oncilla habitat use within them. Additionally, we conducted spatial predictions of habitat use across its northern and southern range in Costa Rica to identify priority conservation areas for the species. We found that Central American clouded oncilla habitat use is driven primarily by environmental factors. Our results showed that oncillas select habitats with denser tree cover at high elevations, closer to permanent water sources, which may provide them with high prey density and a favorable habitat structure for their survival. Spatial predictions identified two main regions as conservation priority areas where threat mitigation efforts and monitoring should be implemented: the Caribbean slope of the Talamanca mountains, and the Arenal-Monteverde forest complex. The occupancy modeling approach turned out to be very useful to assess the spatial associations of the species with the environment and mapping the conservation priority areas. Future research and mitigation actions should focus on potential threats that could negatively impact Central American clouded oncilla populations and habitat use, including the role of mesopredators and feral species.
Assuntos
Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Animais , Costa Rica , Felidae/fisiologiaRESUMO
Recently, the tiger-cat species complex was split into Leopardus tigrinus and Leopardus guttulus, along with other proposed schemes. We performed a detailed analysis integrating ecological modeling, biogeography, and phenotype of the four originally recognized subspecies-tigrinus, oncilla, pardinoides, guttulus-and presented a new multidimensional niche depiction of the species. Species distribution models used > 1400 records from museums and photographs, all checked for species accuracy. Morphological data were obtained from institutional/personal archives. Spotting patterns were established by integrating museum and photographic/camera-trap records. Principal component analysis showed three clearly distinct groups, with the Central American specimens (oncilla) clustering entirely within those of the Andes, namely the pardinoides group of the cloud forests of the southern Central-American and Andean mountain chains (clouded tiger-cat); the tigrinus group of the savannas of the Guiana Shield and central/northeastern Brazil (savanna tiger-cat); and the guttulus group in the lowland forests of the Atlantic Forest domain (Atlantic Forest tiger-cat). This scheme is supported by recent genetic analyses. All species displayed different spotting patterns, with some significant differences in body measurements/proportions. The new distribution presented alarming reductions from the historic range of - 50.4% to - 68.2%. This multidimensional approach revealed a new species of the elusive and threatened tiger-cat complex.
Assuntos
Tigres , Animais , Filogenia , Florestas , BrasilRESUMO
A new species of hylid frog is described from Tapir Valley Nature Reserve, located on the Caribbean slope of Tenorio Volcano in Bijagua, Alajuela Province, Costa Rica. A molecular phylogenetic analysis supports its inclusion in the genus Tlalocohyla. Morphological, morphometric, larval, and acoustic characteristics further distinguish it from other species in the genus and support its uniqueness. The new species is closely related to T. picta and T. smithii, and is separated by at least 500 kilometers from the nearest known occurrence of a population of T. picta in southern Honduras. The new species is readily distinguished from all other Tlalocohyla by its brilliant green coloration marked with a pronounced, incomplete light dorsolateral stripe that is bordered above by a diffuse reddish-brown stripe. Its dorsum is marked with bold reddish brown spots and its ventral skin is fully transparent. This new Tlalocohyla is currently only known from the type locality, where it inhabits a lentic wetland system with an emergent herbaceous vegetation-dominated benthic zone, surrounded by tropical rainforest. A description of its bioacoustic repertoire and information on natural history, reproduction and habitat preference of this new species are provided.
Assuntos
Anuros , Rana clamitans , Animais , Costa Rica , Filogenia , Compostos de Amônio QuaternárioRESUMO
Objective: This study's main objective was to analyze the antibiotic susceptibility profile of Escherichia coli isolates obtained from a fecal sample of a captive Baird's tapir (Tapirus bairdii) in Costa Rica. Materials and Methods: The fecal sample was collected inside the enclosure on March 3, 2017, right after the animal defecated. Samples were cultured on MacConkey agar plates nonsupplemented and supplemented with 2 µg/mL of cefotaxime. Bacterial identification and antibiotic susceptibility were performed with the Vitek 2 Compact System and the Kirby Bauer disk diffusion method, respectively. Polymerase chain reaction amplification was performed to detect blaCTX-M beta-lactamase genes. Resistant isolates were subjected to whole-genome sequencing (WGS). Results: After evaluating several antibiotic classes, a multidrug-resistant E. coli strain with extended-spectrum beta-lactamase phenotype was isolated. Resistance to cefotaxime, cefepime, ampicillin, ampicillin/sulbactam, and tetracycline was detected. WGS analysis showed the presence of blaCTX-M-1, blaTEM-1B, and tet(B) genes. The presence of IncN plasmids and Col156 was also detected. Conclusion: Our findings are according with the notion that animals' high density enhances the spread of resistant determinants in a captive environment in a limited space, where the likelihood of direct or indirect contact with other animals and humans is more frequent.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , beta-Lactamases/genética , Doenças dos Animais/microbiologia , Animais , Infecções por Escherichia coli , Fezes/microbiologia , Feminino , Genes Bacterianos , Testes de Sensibilidade Microbiana , Perissodáctilos , PlasmídeosRESUMO
OBJECTIVES: The main objective of this study was to analyse the antimicrobial susceptibility profile of Escherichia coli isolates obtained from faecal samples of free-ranging Baird's tapirs (Tapirus bairdii) in the northwestern region of the Talamanca Mountain Range, Costa Rica. METHODS: Faecal samples were collected by opportunistic search of the study area from February-September 2017 during seven field expeditions. Escherichia coli isolates were recovered using selective and differential MacConkey agar medium and were subjected to biochemical identification and antimicrobial susceptibility testing using a VITEK®2 Compact automated system and the AST-N279 card. RESULTS: A total of 60 E. coli isolates were obtained from 63 faecal samples. Following evaluation of nine different antimicrobial classes, 98% (59/60) of the isolates were characterised as pansusceptible; only 1 isolate presented resistance to nalidixic acid. CONCLUSION: We propose that the commensal intestinal microbiota of free-ranging Baird's tapirs in this area remains isolated from antibiotic selective pressure, probably because seven different protected areas converge, thus giving a possible low anthropogenic activity to the region.
Assuntos
Antibacterianos/farmacologia , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Perissodáctilos/microbiologia , Seleção Genética , Animais , Costa Rica , Farmacorresistência Bacteriana , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Testes de Sensibilidade MicrobianaRESUMO
Aposematism and crypsis are often viewed as two extremes of a continuum of visual conspicuousness to predators. Theory predicts that behavioral and coloration conspicuousness should vary in tandem along the conspicuousness spectrum for antipredator strategies to be effective. Here we used visual modeling of contrast and behavioral observations to examine the conspicuousness of four populations of the granular poison frog, Oophaga granulifera, which exhibits almost continuous variation in dorsal color. The patterns of geographic variation in color, visual contrast, and behavior support a gradient of overall conspicuousness along the distribution of O. granulifera. Red and green populations, at the extremes of the color distribution, differ in all elements of color, contrast, and behavior, strongly reflecting aposematic and cryptic strategies. However, there is no smooth cline in any elements of behavior or coloration between the two extremes. Instead populations of intermediate colors attain intermediate conspicuousness by displaying different combinations of aposematic and cryptic traits. We argue that coloration divergence among populations may be linked to the evolution of a gradient of strategies to balance the costs of detection by predators and the benefits of learned aversion.
Assuntos
Adaptação Biológica/fisiologia , Animais Peçonhentos/fisiologia , Anuros/fisiologia , Comportamento Animal/fisiologia , Evolução Biológica , Pigmentação da Pele/fisiologia , Animais , Costa Rica , Modelos Biológicos , Observação , Panamá , Análise EspectralRESUMO
Resumen El uso de técnicas no invasivas ni estresantes para determinar perfiles hormonales, como la medición de esteroides fecales, ha incrementado la comprensión de la fisiología reproductiva en animales silvestres. Debido a la escasa información con respecto a perfiles hormonales reproductivos del perezoso de dos dedos, Choloepus hoffmani, se realizó un estudio en hembras en cautiverio en el centro de rescate "Sloth Sanctuary" (Cahuita, Limón, Costa Rica) con el fin de determinar (i) la confiabilidad de la extracción de progesterona y estradiol en heces, y su cuantificación en el analizador AIA-360®, (ii) evaluar los parámetros sanguíneos en esta especie y (iii) establecer si existe una correlación entre los esteroides plasmáticos y fecales. El estudio se realizó en un periodo de tres meses, durante noviembre de 2013 a enero de 2014, con un total de 208 muestras de heces provenientes de cinco hembras sexualmente maduras, con peso promedio de 6.32 kg. El promedio de las concentraciones medianas en las heces de las cinco hembras fue 124.21 ng/g para progesterona y 1 708.95 pg/g de estradiol. En plasma, los valores de mediana fueron 1.26 ng/mL con un mínimo de 0.32 ng/mL y 12.84 ng/mL como valor máximo; los valores plasmáticos de estrógeno se encontraron por debajo del límite de detección del equipo (25 pg/mL). Aunque no se encontró una correlación estadísticamente significativa entre la progesterona plasmática y la fecal, nuestros datos sugieren que los eventos plasmáticos se reflejan en heces durante los dos días posteriores. Asimismo, los niveles de progesterona se mantuvieron elevados durante la primera mitad de noviembre, y posteriormente mostraron una reducción importante en todas las hembras. Nuestros resultados demuestran que las extracciones en heces y su medición en el AIA-360® permiten la detección y el seguimiento de variaciones hormonales en C. hoffmani, aunque no remplaza las mediciones plasmáticas para determinar valores absolutos.
Abstract In wild animal species, the use of non-invasive and non-stressful procedures to determine hormone profiles, such as fecal steroid measurements, has considerably increased the comprehension of their reproductive physiology. Since there is limited information related to the reproductive hormone profiles of the two-toed sloth, Choloepus hoffmani, a study was conducted in captive specimens at the "Sloth Sanctuary" (Cahuita, Limón, Costa Rica), in order to determine: (i) the reliability of the fecal progesterone and estrogen extraction and its quantification with an AIA-360® analyzer, (ii) assess blood parameters in this species and (iii) evaluate if there is a correlation between fecal and plasmatic steroids. The study was performed over a three-month period, from November, 2013 to January, 2014, with a total amount of 208 fecal samples collected from five sexually mature females weighing 6.32 kg in average. The average of the median concentrations of progesterone in feces of the five females was 124.21 ng/g, and 1 708.95 pg/g for estrogen. The average minimal and maximal values were 50.96 ng/g and 1 057.46 ng/g for progesterone and, 1 191.77 pg/g and 2 159.24 pg/g for estradiol. In plasma, progesterone median values were 1.26 ng/mL, showing a minimum of 0.32 ng/mL and 12.84 ng/mL as maximum values. The plasmatic estrogen levels were below the detection limit of the equipment (25 pg/mL). Although there was no strong statistical correlation between the fecal and plasmatic progesterone fluctuations, our data suggests that the plasmatic events are mostly reflected in feces two days afterwards. Also, the levels of progesterone were elevated during the first half of November and, subsequently, showed a successive and important reduction in all the females tested. Finally, our results demonstrated that fecal steroid extractions and their measurement in a AIA-360®, allowed the successful detection and represents an alternative non-invasive determination of hormone profiles in C. hoffmani. Rev. Biol. Trop. 66(1): 280-292. Epub 2018 March 01.