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1.
Sci Rep ; 14(1): 1673, 2024 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-38242939

RESUMEN

Efficient monitoring of biodiversity-rich areas in conflict-affected areas with poor rule of law requires a combination of different analytical approaches to account for data biases and incompleteness. In the upland Amazon region of Venezuela, in Canaima National Park, we initiated biodiversity monitoring in 2015, but it was interrupted by the establishment of a large-scale mining development plan in 2016, compromising the temporal and geographical extent of monitoring and the security of researchers. We used a resource selection function model framework that considers imperfect detectability and supplemented detections from camera trap surveys with opportunistic off-camera records (including animal tracks and direct sighting) to (1) gain insight into the value of additional occurrence records to accurately predict wildlife resource use in the perturbated area (deforestation, fire, swidden agriculture, and human settlements vicinity), (2) when faced with security and budget constraints. Our approach maximized the use of available data and accounted for biases and data gaps. Adding data from poorly sampled areas had mixed results on estimates of resource use for restricted species, but improved predictions for widespread species. If budget or resources are limited, we recommend focusing on one location with both on-camera and off-camera records over two with cameras. Combining camera trap records with other field observations (28 mammals and 16 birds) allowed us to understand responses of 17 species to deforestation, 15 to fire, and 13 to swidden agriculture. Our study encourages the use of combinations of methods to support conservation in high-biodiversity sites, where access is restricted, researchers are vulnerable, and unequal sampling efforts exist.


Asunto(s)
Animales Salvajes , Conservación de los Recursos Naturales , Animales , Humanos , Venezuela , Conservación de los Recursos Naturales/métodos , Biodiversidad , Mamíferos/fisiología
3.
PeerJ ; 9: e11612, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34178472

RESUMEN

BACKGROUND: Human encroachment and overexploitation of natural resources in the Neotropics is constantly increasing. Indigenous communities all across the Amazon, are trapped between a population rise and a hot debate about the sustainability of hunting rates. The Garden Hunting hypothesis states that shifting cultivation schemes (conucos) used by Amazon indigenous communities may generate favorable conditions, increasing abundance of small and medium wildlife species close to the 'gardens' providing game for indigenous hunters. METHODS: Here, we combined camera trap surveys and spatially explicit interview dataset on Pemón indigenous hunting scope and occurrence in a mosaic of savanna and forest in the Gran Sabana, Venezuela to evaluate to what extent the wildlife resource use corresponds to Garden Hunting hypothesis. We applied the Royle-Nichols model and binomial regression in order to: (1) assess whether abundance of small and medium wildlife species is higher close to conucos and (2) evaluate whether hunters select hunting localities based on accessibility to wildlife resources (closeness to conuco) more than wildlife abundance. RESULTS: We find mixed evidence supporting the Garden Hunting hypothesis predictions. Abundance of small and medium species was high close to conucos but the pattern was not statistically significant for most of them. Pemón seem to hunt in locations dominated by forest, where species abundance was predicted to be higher, than in close vicinity to conucos. Hunting scope was focused on the most abundant species located close to the conuco (Cuniculus paca), but also in less abundant and unavailable species (Crax alector, Tapirus terrestris and Odocoileus virginianus). CONCLUSIONS: Our research provided the first attempt of a systematic sampling survey in the Gran Sabana, generating a quantitative dataset that not only describes the current pattern of wildlife abundance, but sets the base-line to monitor temporal and spatial change in this region of highland Amazon. We discuss the applicability of the estimates generated as a baseline as well as, environmental challenges imposed by economic, social and cultural changes such as mining encroachment for wildlife management.

4.
Neotrop Entomol ; 50(2): 218-228, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33620710

RESUMEN

A new species of Protopedaliodes Viloria & Pyrcz, a satyrine butterfly genus endemic to the highest part of the Guyana Shield, P. arekuna Pyrcz & Stachowicz n. sp., is described from the summit area, ca. 2400 m, of Tramen Tepui, an isolated mountain situated on the Venezuela-Guyana border. It is a remarkable finding as it is probably a narrow endemic, and only the fourth known member of the genus. Morphologically it most closely resembles P. kukenani Viloria & Pyrcz from the Roraima-Kukenán twin peaks. COI barcode analysis shows, however, high genetic distances between these two species, 9-10%. Protopedaliodes taxonomy is briefly revised, from the perspective of the monophyly of the genus based on preliminary molecular and morphological comparative data, including the female genitalia described for the first time for P. kukenani and P. ridouti Viloria & Pyrcz.


Asunto(s)
Mariposas Diurnas , Animales , Mariposas Diurnas/anatomía & histología , Mariposas Diurnas/clasificación , Ambiente , Femenino , Guyana , Venezuela
5.
Environ Sci Pollut Res Int ; 20(1): 390-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22669565

RESUMEN

Living in an area chronically polluted with metals is usually associated with changes in the energy distribution in organisms due to increased energy expenses associated with detoxification and excretion processes. These expenses may be reflected in the available energy resources, such as lipids, carbohydrates, and proteins. In this context, the energy status of Pterostichus oblongopunctatus (Coleoptera: Carabidae) was studied in two metal pollution gradients near Olkusz and Miateczko Slaskie in southern Poland. Both regions are rich in metal ores, and the two largest Polish zinc smelters have been operating there since the 1970s. Beetles were collected from five sites at each gradient. Zinc and cadmium concentrations were measured in both the soil and the beetles. The possible reduction in energy reserves as a cost of detoxifying assimilated metals was evaluated biochemically by determining the total lipid, carbohydrates, and protein contents. At the most polluted sites, the Zn concentration in the soil organic layer reached 2,906 mg/kg, and the Cd concentration reached 55 mg/kg. Body Zn and Cd concentrations increased with increasing soil Zn and Cd concentrations (p = 0.003 and p = 0.0001, respectively). However, no relationship between pollution level and energetic reserves was found. The results suggest that populations of P. oblongopunctatus inhabiting highly metal-polluted sites are able to survive without any serious impact on their energy reserves, though they obviously have to cope with elevated body metal concentrations.


Asunto(s)
Escarabajos/metabolismo , Monitoreo del Ambiente , Metales/metabolismo , Contaminantes del Suelo/metabolismo , Animales , Cadmio/metabolismo , Escarabajos/fisiología , Contaminación Ambiental/estadística & datos numéricos , Inactivación Metabólica , Metales/toxicidad , Polonia , Suelo/química , Contaminantes del Suelo/toxicidad , Zinc/metabolismo
6.
Ecotoxicology ; 22(1): 118-24, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23090483

RESUMEN

To address the question about costs of living in polluted areas, biomarkers linked to metabolism were measured in Pterostichus oblongopunctatus (Coleoptera: Carabidae) collected along two metal-pollution gradients in the vicinity of the two largest Polish zinc smelters: 'Boleslaw' and 'Miasteczko Slaskie' in southern Poland. Both gradients covered a broad range of Zn and Cd concentrations in the humus layer (109-6151 and 1.48-71.4 mg kg(-1), respectively) and body metal concentrations increased with increasing soil metal concentrations. The whole-organism respiration rate was measured as oxygen consumption with Micro-Oxymax respirometer, and cellular energy consumption-as the activity of electron transport system, which is linked to cellular respiration rate. The significant increase in the whole-organism respiration rate with the body metal concentration was found when taking into account other factors such as body mass, gradient (or year of sampling as the beetles were collected on the gradients in different years) and the interactions: body metal concentrations × collection date, body metal concentrations × body mass, and body mass × gradient/sampling year. However, no relationships between metal concentrations in soil or body metal concentrations and the whole-organism or cellular respiration rate could be detected when using mean values per site, underlining the crucial importance of incorporating individual variability in such analyses. The observed increase of the whole-organism respiration rate with increasing body contamination with metals suggests that P. oblongopunctatus incurs energetic expenditures resulting from the necessity to facilitate metal elimination or repair of toxicant-induced damage.


Asunto(s)
Cadmio/toxicidad , Escarabajos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Zinc/toxicidad , Animales , Biomarcadores/metabolismo , Cadmio/farmacocinética , Transporte de Electrón/efectos de los fármacos , Monitoreo del Ambiente/métodos , Contaminación Ambiental/efectos adversos , Consumo de Oxígeno/efectos de los fármacos , Polonia , Respiración/efectos de los fármacos , Contaminantes del Suelo/farmacocinética , Distribución Tisular , Zinc/farmacocinética
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