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1.
Conserv Biol ; : e14221, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37937455

RESUMEN

Reliable maps of species distributions are fundamental for biodiversity research and conservation. The International Union for Conservation of Nature (IUCN) range maps are widely recognized as authoritative representations of species' geographic limits, yet they might not always align with actual occurrence data. In recent area of habitat (AOH) maps, areas that are not habitat have been removed from IUCN ranges to reduce commission errors, but their concordance with actual species occurrence also remains untested. We tested concordance between occurrences recorded in camera trap surveys and predicted occurrences from the IUCN and AOH maps for 510 medium- to large-bodied mammalian species in 80 camera trap sampling areas. Across all areas, cameras detected only 39% of species expected to occur based on IUCN ranges and AOH maps; 85% of the IUCN only mismatches occurred within 200 km of range edges. Only 4% of species occurrences were detected by cameras outside IUCN ranges. The probability of mismatches between cameras and the IUCN range was significantly higher for smaller-bodied mammals and habitat specialists in the Neotropics and Indomalaya and in areas with shorter canopy forests. Our findings suggest that range and AOH maps rarely underrepresent areas where species occur, but they may more often overrepresent ranges by including areas where a species may be absent, particularly at range edges. We suggest that combining range maps with data from ground-based biodiversity sensors, such as camera traps, provides a richer knowledge base for conservation mapping and planning.


Combinación de censos con fototrampas y mapas de extensión de la UICN para incrementar el conocimiento sobre la distribución de las especies Resumen Los mapas confiables de la distribución de las especies son fundamentales para la investigación y conservación de la biodiversidad. Los mapas de distribución de la Unión Internacional para la Conservación de la Naturaleza (UICN) están reconocidos como representaciones de autoridad de los límites geográficos de las especies, aunque no siempre se alinean con los datos actuales de su presencia. En los mapas recientes de área de hábitat (ADH), las áreas que no son hábitat han sido eliminadas de la distribución de la UICN para reducir los errores de comisión, pero su concordancia con la presencia actual de las especies tampoco ha sido analizada. Analizamos la concordancia entre la presencia registrada por los censos de fototrampas y pronosticamos la presencia a partir de los mapas de la UICN y de ADH de 510 especies de mamíferos de talla mediana a grande en 80 áreas de muestreo de fototrampas. Las cámaras detectaron sólo el 39% de las especies esperadas con base en la distribución de la UICN y los mapas de ADH en todas las áreas; el 85% de las disparidades con la UICN ocurrieron dentro de los 200 km a partir del borde de la distribución. Sólo el 4% de la presencia de las especies fue detectada por las cámaras ubicadas fuera de la distribución de la UICN. La probabilidad de disparidad entre las cámaras y la UICN fue significativamente mayor para los mamíferos de talla pequeña y para los especialistas de hábitat en las regiones Neotropical e Indomalaya y en áreas con doseles forestales más bajos. Nuestros hallazgos sugieren que los mapas de distribución y ADH pocas veces subrepresentan las áreas con presencia de las especies, pero con frecuencia pueden sobrerrepresentar la distribución al incluir áreas en donde las especies pueden estar ausentes, en particular los bordes de la distribución. Sugerimos que la combinación de los mapas de distribución con los sensores de biodiversidad en tierra, como las fototrampas, proporciona una base más rica de conocimiento para el mapeo y la planeación de la conservación.

2.
Proc Biol Sci ; 289(1978): 20220457, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35858066

RESUMEN

The structure of forest mammal communities appears surprisingly consistent across the continental tropics, presumably due to convergent evolution in similar environments. Whether such consistency extends to mammal occupancy, despite variation in species characteristics and context, remains unclear. Here we ask whether we can predict occupancy patterns and, if so, whether these relationships are consistent across biogeographic regions. Specifically, we assessed how mammal feeding guild, body mass and ecological specialization relate to occupancy in protected forests across the tropics. We used standardized camera-trap data (1002 camera-trap locations and 2-10 years of data) and a hierarchical Bayesian occupancy model. We found that occupancy varied by regions, and certain species characteristics explained much of this variation. Herbivores consistently had the highest occupancy. However, only in the Neotropics did we detect a significant effect of body mass on occupancy: large mammals had lowest occupancy. Importantly, habitat specialists generally had higher occupancy than generalists, though this was reversed in the Indo-Malayan sites. We conclude that habitat specialization is key for understanding variation in mammal occupancy across regions, and that habitat specialists often benefit more from protected areas, than do generalists. The contrasting examples seen in the Indo-Malayan region probably reflect distinct anthropogenic pressures.


Asunto(s)
Ecosistema , Bosques , Animales , Teorema de Bayes , Biodiversidad , Conservación de los Recursos Naturales , Herbivoria , Mamíferos
3.
Glob Chang Biol ; 28(24): 7205-7216, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36172946

RESUMEN

The spatial aggregation of species pairs often increases with the ecological similarity of the species involved. However, the way in which environmental conditions and anthropogenic activity affect the relationship between spatial aggregation and ecological similarity remains unknown despite the potential for spatial associations to affect species interactions, ecosystem function, and extinction risk. Given that human disturbance has been shown to both increase and decrease spatial associations among species pairs, ecological similarity may have a role in mediating these patterns. Here, we test the influences of habitat diversity, primary productivity, human population density, and species' ecological similarity based on functional traits (i.e., functional trait similarity) on spatial associations among tropical forest mammals. Large mammals are highly sensitive to anthropogenic change and therefore susceptible to changes in interspecific spatial associations. Using two-species occupancy models and camera trap data, we quantified the spatial overlap of 1216 species pairs from 13 tropical forest protected areas around the world. We found that the association between ecological similarity and interspecific species associations depended on surrounding human density. Specifically, aggregation of ecologically similar species was more than an order of magnitude stronger in landscapes with the highest human density compared to those with the lowest human density, even though all populations occurred within protected areas. Human-induced changes in interspecific spatial associations have been shown to alter top-down control by predators, increase disease transmission and increase local extinction rates. Our results indicate that anthropogenic effects on the distribution of wildlife within protected areas are already occurring and that impacts on species interactions, ecosystem functions, and extinction risk warrant further investigation.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Humanos , Bosques , Mamíferos , Densidad de Población
4.
Proc Biol Sci ; 288(1945): 20202098, 2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33593187

RESUMEN

A variety of factors can affect the biodiversity of tropical mammal communities, but their relative importance and directionality remain uncertain. Previous global investigations of mammal functional diversity have relied on range maps instead of observational data to determine community composition. We test the effects of species pools, habitat heterogeneity, primary productivity and human disturbance on the functional diversity (dispersion and richness) of mammal communities using the largest standardized tropical forest camera trap monitoring system, the Tropical Ecology Assessment and Monitoring (TEAM) Network. We use occupancy values derived from the camera trap data to calculate occupancy-weighted functional diversity and use Bayesian generalized linear regression to determine the effects of multiple predictors. Mammal community functional dispersion increased with primary productivity, while functional richness decreased with human-induced local extinctions and was significantly lower in Madagascar than other tropical regions. The significant positive relationship between functional dispersion and productivity was evident only when functional dispersion was weighted by species' occupancies. Thus, observational data from standardized monitoring can reveal the drivers of mammal communities in ways that are not readily apparent from range map-based studies. The positive association between occupancy-weighted functional dispersion of tropical forest mammal communities and primary productivity suggests that unique functional traits may be more beneficial in more productive ecosystems and may allow species to persist at higher abundances.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Teorema de Bayes , Bosques , Humanos , Madagascar , Mamíferos , Clima Tropical
5.
PLoS Biol ; 14(1): e1002357, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26785119

RESUMEN

Extinction rates in the Anthropocene are three orders of magnitude higher than background and disproportionately occur in the tropics, home of half the world's species. Despite global efforts to combat tropical species extinctions, lack of high-quality, objective information on tropical biodiversity has hampered quantitative evaluation of conservation strategies. In particular, the scarcity of population-level monitoring in tropical forests has stymied assessment of biodiversity outcomes, such as the status and trends of animal populations in protected areas. Here, we evaluate occupancy trends for 511 populations of terrestrial mammals and birds, representing 244 species from 15 tropical forest protected areas on three continents. For the first time to our knowledge, we use annual surveys from tropical forests worldwide that employ a standardized camera trapping protocol, and we compute data analytics that correct for imperfect detection. We found that occupancy declined in 22%, increased in 17%, and exhibited no change in 22% of populations during the last 3-8 years, while 39% of populations were detected too infrequently to assess occupancy changes. Despite extensive variability in occupancy trends, these 15 tropical protected areas have not exhibited systematic declines in biodiversity (i.e., occupancy, richness, or evenness) at the community level. Our results differ from reports of widespread biodiversity declines based on aggregated secondary data and expert opinion and suggest less extreme deterioration in tropical forest protected areas. We simultaneously fill an important conservation data gap and demonstrate the value of large-scale monitoring infrastructure and powerful analytics, which can be scaled to incorporate additional sites, ecosystems, and monitoring methods. In an era of catastrophic biodiversity loss, robust indicators produced from standardized monitoring infrastructure are critical to accurately assess population outcomes and identify conservation strategies that can avert biodiversity collapse.


Asunto(s)
Biodiversidad , Aves , Conservación de los Recursos Naturales , Bosques , Mamíferos , Animales , Ecología/métodos , Clima Tropical
7.
Nat Ecol Evol ; 7(7): 1092-1103, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37365343

RESUMEN

Protected areas (PAs) play a vital role in wildlife conservation. Nonetheless there is concern and uncertainty regarding how and at what spatial scales anthropogenic stressors influence the occurrence dynamics of wildlife populations inside PAs. Here we assessed how anthropogenic stressors influence occurrence dynamics of 159 mammal species in 16 tropical PAs from three biogeographic regions. We quantified these relationships for species groups (habitat specialists and generalists) and individual species. We used long-term camera-trap data (1,002 sites) and fitted Bayesian dynamic multispecies occupancy models to estimate local colonization (the probability that a previously empty site is colonized) and local survival (the probability that an occupied site remains occupied). Multiple covariates at both the local scale and landscape scale influenced mammal occurrence dynamics, although responses differed among species groups. Colonization by specialists increased with local-scale forest cover when landscape-scale fragmentation was low. Survival probability of generalists was higher near the edge than in the core of the PA when landscape-scale human population density was low but the opposite occurred when population density was high. We conclude that mammal occurrence dynamics are impacted by anthropogenic stressors acting at multiple scales including outside the PA itself.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Humanos , Animales , Teorema de Bayes , Bosques , Mamíferos , Animales Salvajes
8.
Nat Commun ; 13(1): 7102, 2022 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-36402775

RESUMEN

An animal's daily use of time (their "diel activity") reflects their adaptations, requirements, and interactions, yet we know little about the underlying processes governing diel activity within and among communities. Here we examine whether community-level activity patterns differ among biogeographic regions, and explore the roles of top-down versus bottom-up processes and thermoregulatory constraints. Using data from systematic camera-trap networks in 16 protected forests across the tropics, we examine the relationships of mammals' diel activity to body mass and trophic guild. Also, we assess the activity relationships within and among guilds. Apart from Neotropical insectivores, guilds exhibited consistent cross-regional activity in relation to body mass. Results indicate that thermoregulation constrains herbivore and insectivore activity (e.g., larger Afrotropical herbivores are ~7 times more likely to be nocturnal than smaller herbivores), while bottom-up processes constrain the activity of carnivores in relation to herbivores, and top-down processes constrain the activity of small omnivores and insectivores in relation to large carnivores' activity. Overall, diel activity of tropical mammal communities appears shaped by similar processes and constraints among regions reflecting body mass and trophic guilds.


Asunto(s)
Carnívoros , Bosques , Animales , Herbivoria , Estado Nutricional
9.
Sci Total Environ ; 789: 147946, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34058582

RESUMEN

In a scenario where escalating human activities lead to several environmental changes and, consequently, affect mammal abundance and distribution, ß-diversity may increase due to differences among sites. Using the ecological uniqueness approach, we analyzed ß-diversity patterns of ground-dwelling mammal communities recorded through comprehensive camera trap monitoring within eight tropical forests protected areas in Mesoamerica and South America under variable landscape contexts. We aimed to investigate whether the contribution of single sites (LCBD) and single species (SCBD) to overall ß-diversity could be explained by community metrics and environmental variables, and by species metrics and biological traits, respectively. Total ß-diversity was also partitioned into species replacement and richness difference. We related LCBD to species richness, total relative abundance, functional indices, and environmental variables (tree basal area, protected area size, NDVI, and precipitation seasonality), and SCBD to species naïve occupancy, relative abundance, and morphoecological traits via beta regression. Our findings showed that LCBD was primarily explained by variation in species richness, rather than relative abundance and functional metrics. Protected area size and tree basal area were also important in explaining variation in LCBD. SCBD was strongly related to naïve occupancy and relative abundance, but not to biological traits, such as body mass, trophic energy level, activity cycle, and taxonomic category. Local ß-diversity was a result of species replacements and to a lesser extent differences in species richness. Our approach was useful in examining and comparing the ecological uniqueness among different sites, revealing the regional scale current status of mammal diversity. High LCBD values comprised sites embedded within smaller habitat extents, hosting lower tree basal areas, and harboring low species richness. SCBD showed that relatively ubiquitous species that occur at variable abundances across sites contributed most to ß-diversity.


Asunto(s)
Ecosistema , Mamíferos , Animales , Biodiversidad , Bosques , Humanos , América del Sur , Árboles
10.
PLoS One ; 14(3): e0213671, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30861045

RESUMEN

Carnivores have long been used as model organisms to examine mechanisms that allow coexistence among ecologically similar species. Interactions between carnivores, including competition and predation, comprise important processes regulating local community structure and diversity. We use data from an intensive camera-trapping monitoring program across eight Neotropical forest sites to describe the patterns of spatiotemporal organization of a guild of five sympatric cat species: jaguar (Panthera onca), puma (Puma concolor), ocelot (Leopardus pardalis), jaguarundi (Herpailurus yagouaroundi) and margay (Leopardus wiedii). For the three largest cat species, we developed multi-stage occupancy models accounting for habitat characteristics (landscape complexity and prey availability) and models accounting for species interactions (occupancy estimates of potential competitor cat species). Patterns of habitat-use were best explained by prey availability, rather than habitat structure or species interactions, with no evidence of negative associations of jaguar on puma and ocelot occupancy or puma on ocelot occupancy. We further explore temporal activity patterns and overlap of all five felid species. We observed a moderate temporal overlap between jaguar, puma and ocelot, with differences in their activity peaks, whereas higher temporal partitioning was observed between jaguarundi and both ocelot and margay. Lastly, we conducted temporal overlap analysis and calculated species activity levels across study sites to explore if shifts in daily activity within species can be explained by varying levels of local competition pressure. Activity patterns of ocelots, jaguarundis and margays were similarly bimodal across sites, but pumas exhibited irregular activity patterns, most likely as a response to jaguar activity. Activity levels were similar among sites and observed differences were unrelated to competition or intraguild killing risk. Our study reveals apparent spatial and temporal partitioning for most of the species pairs analyzed, with prey abundance being more important than species interactions in governing the local occurrence and spatial distribution of Neotropical forest felids.


Asunto(s)
Felidae/fisiología , Panthera/fisiología , Conducta Predatoria , Puma/fisiología , Animales , Biodiversidad , Peso Corporal , Brasil , Carnívoros , Bosques , Geografía , Especificidad de la Especie , Clima Tropical
11.
PLoS One ; 13(1): e0189740, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29298311

RESUMEN

Roads are a main threat to biodiversity conservation in the Amazon, in part, because roads increase access for hunters. We examine how increased landscape access by hunters may lead to cascading effects that influence the prey community and abundance of the jaguar (Panthera onca), the top Amazonian terrestrial predator. Understanding such ecological effects originating from anthropogenic actions is essential for conservation and management of wildlife populations in areas undergoing infrastructure development. Our study was conducted in Yasuní Biosphere Reserve, the protected area with highest potential for jaguar conservation in Ecuador, and an area both threatened by road development and inhabited by indigenous groups dependent upon bushmeat. We surveyed prey and jaguar abundance with camera traps in four sites that differed in accessibility to hunters and used site occupancy and spatially explicit capture-recapture analyses to evaluate prey occurrence and estimate jaguar density, respectively. Higher landscape accessibility to hunters was linked with lower occurrence and biomass of game, particularly white-lipped peccary (Tayassu pecari) and collared peccary (Pecari tajacu), the primary game for hunters and prey for jaguars. Jaguar density was up to 18 times higher in the most remote site compared to the most accessible site. Our results provide a strong case for the need to: 1) consider conservation of large carnivores and other wildlife in policies about road construction in protected areas, 2) coordinate conservation initiatives with local governments so that development activities do not conflict with conservation objectives, and 3) promote development of community-based strategies for wildlife management that account for the needs of large carnivores.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Panthera , Transportes , Animales , Biodiversidad , Ecuador , Dinámica Poblacional
12.
Data Brief ; 19: 1670-1682, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30229042

RESUMEN

This article contains data of the horizontal hydraulic conductivity of five different fine-grained soils of the former Lake Texcoco. The data were back-calculated from excess pore pressure dissipation measurements collected at 119 locations using piezocone tests (CPTu). The test campaign was part of the geotechnical survey performed for the construction of the New Mexico City International Airport (NAICM). Descriptive statistical parameters of each soil unit are presented and lognormal probability distributions are fitted to describe the natural variability of the horizontal hydraulic conductivity of this site.

13.
Metro cienc ; 29(1 (2021): Enero- Marzo): 7-15, 2021-01-29. ilus, tab
Artículo en Español | LILACS | ID: biblio-1222465

RESUMEN

El ingreso a la UCIP somete al niño a una serie de estímulos y procedimientos estresantes y dolorosos. El uso de analgesia y sedación es un componente central en los cuidados del niño críticamente enfermo para asegurar su confort y seguridad. Es importante durante la prescripción de analgosedación la monitorización continua de sus efectos. Este proceso debe ser vigilado por todos los integrantes del equipo de salud y su familia. Esta guía se basa en los principios propuestos por la iniciativa "Libérame de la UCI", que consisten en un paquete (bundle) de medidas (ABCDEF) para optimizar la recuperación de los pacientes y sus desenlaces. Contiene tablas con la farmacología de los analgésicos y sedantes, con estrategias generales para el manejo de anal-gosedación y prevención del síndrome de abstinencia y delirium. Guía realizada por el equipo multidisciplinario para lograr una adherencia más completa.


ABSTRACT The admission of a child to the PICU subdue stressful and pain stimuli. The use of analgesia and sedation is the main component for the care of the critically ill children to guarantee comfort and security. During the prescription of analgesia and sedation, monitoring of their effects is important. This process must be supervised by the health team and supported by the family. This guide is based on the initiative "PICU liberation" where a bundle of measures (ABCDEF) is used to optimize the recovery and outcome. This guide contains tables of the pharmacology of analgesics and sedatives, some strategies on the use of analgosedation, prevention of withdrawal and delirium. A guide of the multidisciplinary team to achieve a complete adherence.


Asunto(s)
Humanos , Lactante , Preescolar , Niño , Adolescente , Síndrome , Delirio , Analgesia , Hipnóticos y Sedantes , Dolor , Unidades de Cuidados Intensivos
14.
PLoS One ; 9(12): e114916, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25489954

RESUMEN

Protected areas are essential for conservation of wildlife populations. However, in the tropics there are two important factors that may interact to threaten this objective: 1) road development associated with large-scale resource extraction near or within protected areas; and 2) historical occupancy by traditional or indigenous groups that depend on wildlife for their survival. To manage wildlife populations in the tropics, it is critical to understand the effects of roads on the spatial extent of hunting and how wildlife is used. A geographical analysis can help us answer questions such as: How do roads affect spatial extent of hunting? How does market vicinity relate to local consumption and trade of bushmeat? How does vicinity to markets influence choice of game? A geographical analysis also can help evaluate the consequences of increased accessibility in landscapes that function as source-sink systems. We applied spatial analyses to evaluate the effects of increased landscape and market accessibility by road development on spatial extent of harvested areas and wildlife use by indigenous hunters. Our study was conducted in Yasuní Biosphere Reserve, Ecuador, which is impacted by road development for oil extraction, and inhabited by the Waorani indigenous group. Hunting activities were self-reported for 12-14 months and each kill was georeferenced. Presence of roads was associated with a two-fold increase of the extraction area. Rates of bushmeat extraction and trade were higher closer to markets than further away. Hunters located closer to markets concentrated their effort on large-bodied species. Our results clearly demonstrate that placing roads within protected areas can seriously reduce their capacity to sustain wildlife populations and potentially threaten livelihoods of indigenous groups who depend on these resources for their survival. Our results critically inform current policy debates regarding resource extraction and road building near or within protected areas.


Asunto(s)
Conservación de los Recursos Naturales , Geografía , Carne , Transportes , Animales , Animales Salvajes , Especies en Peligro de Extinción , Humanos , Indígenas Sudamericanos
15.
Conserv Biol ; 20(1): 3-13, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16909654

RESUMEN

Conventional graduate training related to tropical conservation and development has typically separated the two fields, with students focusing on either conservation from the perspective of the biophysical sciences or development as an extension of the social sciences. On entering the workforce, however graduates find they are required to work beyond disciplinary boundaries to address the complex interconnectivity between biological conservation and human well-being. We devised a framework for graduate education that broadens students' skill sets to learn outside their immediate disciplines and think in terms of linked socioecological systems, work in teams, communicate in nonacademic formats, and reflect critically on their own perspectives and actions. The University of Florida's Tropical Conservation and Development program has adopted a learning and action platform that blends theory, skills, and praxis to create an intellectual, social, and professionally safe space where students, faculty, and other participants can creatively address the complex challenges of tropical conservation and development. This platform operates within a nondegree-granting program and includes core courses that are taught by a team of biophysical and social scientists. It incorporates a range of alternative learning spaces such as student-led workshops, retreats, visiting professionals, practitioner experiences, and a weekly student-led seminar that collectively encourage students and faculty to enhance their skills and systematically and thoroughly reflect on program activities. Challenges to the described approach include increased service demands on faculty, a redefinition of research excellence to include effective and equitable collaboration with host-country partners, and the trade-offs and uncertainties inherent in more collaborative, interdisciplinary research. Despite these challenges, growing interdisciplinary programs, coupled with adaptive educational approaches that emphasize learning and action networks of students, faculty, and field partners, provide the best hope for responding to the emerging challenges of tropical conservation and development.


Asunto(s)
Conservación de los Recursos Naturales , Educación de Postgrado/métodos , Aprendizaje Basado en Problemas , Educación de Postgrado/normas , Florida , Humanos , Liderazgo , Mentores , Competencia Profesional
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