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Ada Sánchez-Mercado
Instituto Venezolano de Investigaciones Científicas

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Software
Published: 03 August 2021
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Este conjunto de datos incluye tablas resumen con los datos de las cámaras, eventos de fototrampeo e identificaciones utilizados en la publicación Interannual and daily activity patterns of mid-sized mammals in Maracaibo Lake Basin, Venezuela. Primera versión del código para generar tablas de las cámaras, eventos, e identificaciones. La colección de fotografías se encuentra disponible en los conjuntos de datos relacionados.

ACS Style

José R. Ferrer-Paris; Ada Sánchez-Mercado; Lisandro Morán. Registro fotográfico de mamíferos en el Parque Recreativo Burro Negro y la Reserva Nacional Hidráulica de Pueblo Viejo, estado Zulia, Venezuela. 2021, 1 .

AMA Style

José R. Ferrer-Paris, Ada Sánchez-Mercado, Lisandro Morán. Registro fotográfico de mamíferos en el Parque Recreativo Burro Negro y la Reserva Nacional Hidráulica de Pueblo Viejo, estado Zulia, Venezuela. . 2021; ():1.

Chicago/Turabian Style

José R. Ferrer-Paris; Ada Sánchez-Mercado; Lisandro Morán. 2021. "Registro fotográfico de mamíferos en el Parque Recreativo Burro Negro y la Reserva Nacional Hidráulica de Pueblo Viejo, estado Zulia, Venezuela." , no. : 1.

Software
Published: 03 August 2021
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Este conjunto de datos incluye tablas resumen con los datos de las cámaras, eventos de fototrampeo e identificaciones utilizados en la publicación Interannual and daily activity patterns of mid-sized mammals in Maracaibo Lake Basin, Venezuela. Primera versión del código para generar tablas de las cámaras, eventos, e identificaciones. La colección de fotografías se encuentra disponible en los conjuntos de datos relacionados.

ACS Style

José R. Ferrer-Paris; Ada Sánchez-Mercado; Lisandro Morán. Registro fotográfico de mamíferos en el Parque Recreativo Burro Negro y la Reserva Nacional Hidráulica de Pueblo Viejo, estado Zulia, Venezuela. 2021, 1 .

AMA Style

José R. Ferrer-Paris, Ada Sánchez-Mercado, Lisandro Morán. Registro fotográfico de mamíferos en el Parque Recreativo Burro Negro y la Reserva Nacional Hidráulica de Pueblo Viejo, estado Zulia, Venezuela. . 2021; ():1.

Chicago/Turabian Style

José R. Ferrer-Paris; Ada Sánchez-Mercado; Lisandro Morán. 2021. "Registro fotográfico de mamíferos en el Parque Recreativo Burro Negro y la Reserva Nacional Hidráulica de Pueblo Viejo, estado Zulia, Venezuela." , no. : 1.

Review
Published: 29 April 2021 in Diversity
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The order Psittaciformes is one of the most prevalent groups in the illegal wildlife trade. Efforts to understand this threat have focused on describing the elements of the trade itself: actors, extraction rates, and routes. However, the development of policy-oriented interventions also requires an understanding of how research aims and actions are distributed across the trade chain, regions, and species. We used an action-based approach to review documents published on illegal Psittaciformes trade at a global scale to analyze patterns in research aims and actions. Research increased exponentially in recent decades, recording 165 species from 46 genera, with an over representation of American and Australasian genera. Most of the research provided basic knowledge for the intermediary side of the trade chain. Aims such as the identification of network actors, zoonosis control, and aiding physical detection had numerous but scarcely cited documents (low growth rate), while behavior change had the highest growth rate. The Americas had the highest diversity of research aims, contributing with basic knowledge, implementation, and monitoring across the whole trade chain. Better understanding of the supply side dynamics in local markets, actor typology, and actor interactions are needed. Protecting areas, livelihood incentives, and legal substitutes are actions under-explored in parrots, while behavior change is emerging.

ACS Style

Ada Sánchez-Mercado; José Ferrer-Paris; Jon Rodríguez; José L. Tella. A Literature Synthesis of Actions to Tackle Illegal Parrot Trade. Diversity 2021, 13, 191 .

AMA Style

Ada Sánchez-Mercado, José Ferrer-Paris, Jon Rodríguez, José L. Tella. A Literature Synthesis of Actions to Tackle Illegal Parrot Trade. Diversity. 2021; 13 (5):191.

Chicago/Turabian Style

Ada Sánchez-Mercado; José Ferrer-Paris; Jon Rodríguez; José L. Tella. 2021. "A Literature Synthesis of Actions to Tackle Illegal Parrot Trade." Diversity 13, no. 5: 191.

Journal article
Published: 05 September 2020 in Diversity
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The perceptions and attitudes of local communities help understand the social drivers of unsustainable wildlife use and the social acceptability of conservation programs. We evaluated the social context influencing illegal harvesting of the threatened yellow-shouldered Amazon (Amazona barbadensis) and the effectiveness of a longstanding conservation program in the Macanao Peninsula, Margarita Island, Venezuela. We interviewed 496 people from three communities and documented their perceptions about (1) status and the impact of threats to parrot populations, (2) acceptability of the conservation program, and (3) social processes influencing unsustainable parrot use. Approval of the program was high, but it failed to engage communities despite their high conservation awareness and positive attitudes towards the species. People identified unsustainable use as the main threat to parrots, but negative perceptions were limited to selling, not harvesting or keeping. Harvesters with different motivations (keepers, sellers) may occur in Macanao, and social acceptability of both actors may differ. Future efforts will require a stakeholder engagement strategy to manage conflicts and incentives to participation. A better understanding of different categories of harvesters, as well as their motives and role in the illegal trade network would provide insights to the design of a behavior change campaign.

ACS Style

Ada Sánchez-Mercado; Oriana Blanco; Bibiana Sucre-Smith; José Briceño-Linares; Carlos Peláez; Jon Rodríguez. Using Peoples’ Perceptions to Improve Conservation Programs: The Yellow-Shouldered Amazon in Venezuela. Diversity 2020, 12, 342 .

AMA Style

Ada Sánchez-Mercado, Oriana Blanco, Bibiana Sucre-Smith, José Briceño-Linares, Carlos Peláez, Jon Rodríguez. Using Peoples’ Perceptions to Improve Conservation Programs: The Yellow-Shouldered Amazon in Venezuela. Diversity. 2020; 12 (9):342.

Chicago/Turabian Style

Ada Sánchez-Mercado; Oriana Blanco; Bibiana Sucre-Smith; José Briceño-Linares; Carlos Peláez; Jon Rodríguez. 2020. "Using Peoples’ Perceptions to Improve Conservation Programs: The Yellow-Shouldered Amazon in Venezuela." Diversity 12, no. 9: 342.

Journal article
Published: 22 January 2020 in Bird Conservation International
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Summary The global decline in psittacid populations highlights the need for monitoring programmes that allow us to estimate the level of confidence that can be placed in a non-detection observation in order to assess changes in range status. We used the detection/non-detection records for 26 psittacid species detected during the first national bird monitoring programme in Venezuela carried out in 2010 by the Neotropical Biodiversity Mapping Initiative. We fitted occupancy models and evaluate the suitability of the data to explain the lack of detections given the current sampling effort, and the expected occurrence probabilities due to environmental conditions (conditional probability of occurrence; ΨCONDL). We were able to fit reliable models for 13 of the 26 species detected. For Green-rumped ParrotletForpus passerinus, Blue-headed ParrotPionus menstrus, and Orange-winged AmazonAmazona amazonica, the probability of detection (p) under the current sampling effort was too low (> 0.2) in areas where environmental conditions would imply high ΨCONDL(< 0.3). This suggests that sampling effort should be increased to generate reliable estimations of occurrence. In contrast, for Scarlet MacawAra macao, Yellow-crowned AmazonAmazona ochrocephala, Orange-chinned ParakeetBrotogeris jugularisand Brown-throated ParakeetEupsittula pertinaxthe model estimated highp(< 0.3) and low ΨCONDL(> 0.2), suggesting that the species are reliably detected and better models could be obtained by including other predictive variables related to temporal use of resources and habitat heterogeneity. To improve the effectiveness of parrot monitoring programme in Neotropical countries, we suggest increasing the sampling effort, developing several surveys per year, and including variables related with temporal use of resources and habitat heterogeneity.

ACS Style

José R. Ferrer-Paris; Ada Sánchez-Mercado. Making inferences about non-detection observations to improve occurrence predictions in Venezuelan Psittacidae. Bird Conservation International 2020, 30, 406 -422.

AMA Style

José R. Ferrer-Paris, Ada Sánchez-Mercado. Making inferences about non-detection observations to improve occurrence predictions in Venezuelan Psittacidae. Bird Conservation International. 2020; 30 (3):406-422.

Chicago/Turabian Style

José R. Ferrer-Paris; Ada Sánchez-Mercado. 2020. "Making inferences about non-detection observations to improve occurrence predictions in Venezuelan Psittacidae." Bird Conservation International 30, no. 3: 406-422.

Journal article
Published: 30 September 2018 in Therya
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Despite its biogeographic importance, the mammals of Maracaibo lake basin have been poorly studied. The objectives of this study were to: 1) provide a list of the mammal species detected by combining information from camera traps and other sources, and 2) describe diurnal and annual activity patterns for some of the species detected. Camera-trapping was carried out for one year in five localities within the Burro Negro Protection Zone (Spanish acronym ZPBN). Records of terrestrial mammals (excluding Chiroptera) were compiled from: 1) direct and indirect opportunistic records during field visits, 2) informal interviews with local inhabitants, 3) three national natural history collections, and 4) scientific literature. The complementarity between sources, similarity with other localities within the region, and temporal changes in composition were evaluated with the Sørensen Similarity Index (RS), and annual differences in the number of detections per sampling effort were evaluated using a X2 test. Sampling effort was 1,799 camera days, resulting in 569 events of mammal detection recorded and 20 species from 17 families in 9 orders identified. Four species (Dasypus novemcinctus, Dasyprocta leporina, Cerdocyon thous and Leopardus pardalis) were captured all year round. Camera traps detected half of the non-flying mammal species in the area, including five that had not been previously reported by other sources (Cuniculus paca, Coendou prehensilis, Sylvilagus floridanus, Procyon cancrivorus and Puma yagouaroundi). At least three species (Panthera onca, Odocoileus virginianus, and Hydrochoerus hydrochaeris) had been reported as historically abundant, but were not detected during the year of camera trapping, which could be due to recent declines in their populations. Camera trapping provides reliable records on the presence of four species with data gaps in their distribution ranges (Myrmecophaga tetradactyla, Coendou prehensilis, Cerdocyon thous and Procyon cancrivorus), as well as baseline data for evaluating the distribution overlap between pairs of species, such as Tamandua mexicana and T. tetradactyla, and Dasyprocta leporina and D. punctata. A higher species richness was observed between June and August, in the rainy season.

ACS Style

Lisandro Morán; Luis García; José D. Ferrebuz; Roxana Sánchez; Alberto Porta; Ada Sánchez-Mercado; José Rafael Ferrer-Paris. Interannual and daily activity patterns of mid-sized mammals in Maracaibo Lake Basin, Venezuela. Therya 2018, 9, 227 -236.

AMA Style

Lisandro Morán, Luis García, José D. Ferrebuz, Roxana Sánchez, Alberto Porta, Ada Sánchez-Mercado, José Rafael Ferrer-Paris. Interannual and daily activity patterns of mid-sized mammals in Maracaibo Lake Basin, Venezuela. Therya. 2018; 9 (3):227-236.

Chicago/Turabian Style

Lisandro Morán; Luis García; José D. Ferrebuz; Roxana Sánchez; Alberto Porta; Ada Sánchez-Mercado; José Rafael Ferrer-Paris. 2018. "Interannual and daily activity patterns of mid-sized mammals in Maracaibo Lake Basin, Venezuela." Therya 9, no. 3: 227-236.

Research article
Published: 10 December 2017 in Ecology and Evolution
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Species distribution models (SDM) can be valuable for identifying key habitats for conservation management of threatened taxa, but anthropogenic habitat change can undermine SDM accuracy. We used data for the Red Siskin (Spinus cucullatus), a critically endangered bird and ground truthing to examine anthropogenic habitat change as a source of SDM inaccuracy. We aimed to estimate: (1) the Red Siskin's historic distribution in Venezuela; (2) the portion of this historic distribution lost to vegetation degradation; and (3) the location of key habitats or areas with both, a high probability of historic occurrence and a low probability of vegetation degradation. We ground‐truthed 191 locations and used expert opinion as well as landscape characteristics to classify species' habitat suitability as excellent, good, acceptable, or poor. We fit a Random Forest model (RF) and Enhanced Vegetation Index (EVI) time series to evaluate the accuracy and precision of the expert categorization of habitat suitability. We estimated the probability of historic occurrence by fitting a MaxLike model using 88 presence records (1960–2013) and data on forest cover and aridity index. Of the entire study area, 23% (20,696 km2) had a historic probability of Red Siskin occurrence over 0.743. Furthermore, 85% of ground‐truthed locations had substantial reductions in mean EVI, resulting in key habitats totaling just 976 km2, in small blocks in the western and central regions. Decline in Area of Occupancy over 15 years was between 40% and 95%, corresponding to an extinction risk category between Vulnerable and Critically Endangered. Relating key habitats with other landscape features revealed significant risks and opportunities for proposed conservation interventions, including the fact that ongoing vegetation degradation could limit the establishment of reintroduced populations in eastern areas, while the conservation of remaining key habitats on private lands could be improved with biodiversity‐friendly agri‐ and silviculture programs.

ACS Style

Ada Sánchez-Mercado; Kathryn Rodriguez-Clark; Jhonathan Miranda; José R. Ferrer-Paris; Brian Coyle; Samuel Toro; Arlene Cardozo-Urdaneta; Michael J. Braun. How to deal with ground truthing affected by human-induced habitat change?: Identifying high-quality habitats for the Critically Endangered Red Siskin. Ecology and Evolution 2017, 8, 841 -851.

AMA Style

Ada Sánchez-Mercado, Kathryn Rodriguez-Clark, Jhonathan Miranda, José R. Ferrer-Paris, Brian Coyle, Samuel Toro, Arlene Cardozo-Urdaneta, Michael J. Braun. How to deal with ground truthing affected by human-induced habitat change?: Identifying high-quality habitats for the Critically Endangered Red Siskin. Ecology and Evolution. 2017; 8 (2):841-851.

Chicago/Turabian Style

Ada Sánchez-Mercado; Kathryn Rodriguez-Clark; Jhonathan Miranda; José R. Ferrer-Paris; Brian Coyle; Samuel Toro; Arlene Cardozo-Urdaneta; Michael J. Braun. 2017. "How to deal with ground truthing affected by human-induced habitat change?: Identifying high-quality habitats for the Critically Endangered Red Siskin." Ecology and Evolution 8, no. 2: 841-851.

Article
Published: 27 November 2017 in Oryx
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Illegal wildlife trade is one of the major threats to Neotropical psittacids, with nearly 28% of species targeted for the illegal pet trade. We analysed the most comprehensive data set on illegal wildlife trade currently available for Venezuela, from various sources, to provide a quantitative assessment of the magnitude, scope and detectability of the trade in psittacids at the national level. We calculated a specific offer index (SO) based on the frequency of which each species was offered for sale. Forty-seven species of psittacids were traded in Venezuela during 1981–2015, of which 17 were non-native. At least 641,675 individuals were traded, with an overall extraction rate of 18,334 individuals per year (35 years of accumulated reports). Amazona ochrocephala was the most frequently detected species (SO = 3.603), with the highest extraction rate (10,544 individuals per year), followed by Eupsittula pertinax (SO = 1.357) and Amazona amazonica (SO = 1.073). Amazona barbadensis, Ara ararauna and Ara chloropterus were the fourth most frequently detected species (SO = 0.564–0.615). Eleven species were involved principally in domestic trade (> 60% of records). Our approach could be the first step in developing a national monitoring programme to inform national policy on the trade in psittacids. Patterns and numbers provided may be used to update the official list of threatened species, and could also be used in planning conservation actions.

ACS Style

Ada Sánchez-Mercado; Marianne Asmüssen; Jon Paul Rodríguez; Lisandro Moran; Arlene Cardozo-Urdaneta; Lorena Isabel Morales. Illegal trade of the Psittacidae in Venezuela. Oryx 2017, 54, 77 -83.

AMA Style

Ada Sánchez-Mercado, Marianne Asmüssen, Jon Paul Rodríguez, Lisandro Moran, Arlene Cardozo-Urdaneta, Lorena Isabel Morales. Illegal trade of the Psittacidae in Venezuela. Oryx. 2017; 54 (1):77-83.

Chicago/Turabian Style

Ada Sánchez-Mercado; Marianne Asmüssen; Jon Paul Rodríguez; Lisandro Moran; Arlene Cardozo-Urdaneta; Lorena Isabel Morales. 2017. "Illegal trade of the Psittacidae in Venezuela." Oryx 54, no. 1: 77-83.

Journal article
Published: 01 May 2017 in Biological Conservation
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ACS Style

Włodzimierz Jędrzejewski; Rafael Carreño; Ada Sánchez-Mercado; Krzysztof Schmidt; María Abarca; Hugh S. Robinson; Ernesto O. Boede; Rafael Hoogesteijn; Ángel L. Viloria; Hugo Cerda; Grisel Velásquez; Sergio Zambrano-Martínez. Human-jaguar conflicts and the relative importance of retaliatory killing and hunting for jaguar (Panthera onca) populations in Venezuela. Biological Conservation 2017, 209, 524 -532.

AMA Style

Włodzimierz Jędrzejewski, Rafael Carreño, Ada Sánchez-Mercado, Krzysztof Schmidt, María Abarca, Hugh S. Robinson, Ernesto O. Boede, Rafael Hoogesteijn, Ángel L. Viloria, Hugo Cerda, Grisel Velásquez, Sergio Zambrano-Martínez. Human-jaguar conflicts and the relative importance of retaliatory killing and hunting for jaguar (Panthera onca) populations in Venezuela. Biological Conservation. 2017; 209 ():524-532.

Chicago/Turabian Style

Włodzimierz Jędrzejewski; Rafael Carreño; Ada Sánchez-Mercado; Krzysztof Schmidt; María Abarca; Hugh S. Robinson; Ernesto O. Boede; Rafael Hoogesteijn; Ángel L. Viloria; Hugo Cerda; Grisel Velásquez; Sergio Zambrano-Martínez. 2017. "Human-jaguar conflicts and the relative importance of retaliatory killing and hunting for jaguar (Panthera onca) populations in Venezuela." Biological Conservation 209, no. : 524-532.

Journal article
Published: 01 February 2017 in Biological Conservation
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ACS Style

Włodzimierz Jędrzejewski; Ernesto O. Boede; María Abarca; Ada Sánchez-Mercado; José R. Ferrer-Paris; Margarita Lampo; Grisel Velásquez; Rafael Carreño; Ángel L. Viloria; Rafael Hoogesteijn; Hugh S. Robinson; Izabela Stachowicz; Hugo Cerda; María Del Mar Weisz; Tito R. Barros; Gilson A. Rivas; Gilberto Borges; Jesús Molinari; Daniel Lew; Howard Takiff; Krzysztof Schmidt. Predicting carnivore distribution and extirpation rate based on human impacts and productivity factors; assessment of the state of jaguar ( Panthera onca ) in Venezuela. Biological Conservation 2017, 206, 132 -142.

AMA Style

Włodzimierz Jędrzejewski, Ernesto O. Boede, María Abarca, Ada Sánchez-Mercado, José R. Ferrer-Paris, Margarita Lampo, Grisel Velásquez, Rafael Carreño, Ángel L. Viloria, Rafael Hoogesteijn, Hugh S. Robinson, Izabela Stachowicz, Hugo Cerda, María Del Mar Weisz, Tito R. Barros, Gilson A. Rivas, Gilberto Borges, Jesús Molinari, Daniel Lew, Howard Takiff, Krzysztof Schmidt. Predicting carnivore distribution and extirpation rate based on human impacts and productivity factors; assessment of the state of jaguar ( Panthera onca ) in Venezuela. Biological Conservation. 2017; 206 ():132-142.

Chicago/Turabian Style

Włodzimierz Jędrzejewski; Ernesto O. Boede; María Abarca; Ada Sánchez-Mercado; José R. Ferrer-Paris; Margarita Lampo; Grisel Velásquez; Rafael Carreño; Ángel L. Viloria; Rafael Hoogesteijn; Hugh S. Robinson; Izabela Stachowicz; Hugo Cerda; María Del Mar Weisz; Tito R. Barros; Gilson A. Rivas; Gilberto Borges; Jesús Molinari; Daniel Lew; Howard Takiff; Krzysztof Schmidt. 2017. "Predicting carnivore distribution and extirpation rate based on human impacts and productivity factors; assessment of the state of jaguar ( Panthera onca ) in Venezuela." Biological Conservation 206, no. : 132-142.

Journal article
Published: 03 August 2016 in Conservation Biology
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Although most often considered independently, subsistence hunting, domestic trade, and international trade as components of illegal wildlife use (IWU) may occurs near one another (spatially correlated). Understanding how and where subsistence and commercial uses may co-occur has important implications for the design and implementation of effective conservation actions. We analyzed patterns in the joint geographical distribution of illegal commercial and subsistence use of multiple wildlife species in Venezuela and evaluated whether available data were sufficient to provide accurate estimates of the magnitude, scope and detectability of IWU. We compiled records of illegal subsistence hunting and trade from several sources and fitted a Random Forest classification model to predict the spatial distribution of IWUs. From 1969 to 2014, 404 species and 8,340,921 specimens were involved in IWU, yielding a mean extraction rate of 185,354 ind./y. Birds were the most speciose group involved (248 spp.), but reptiles experienced the highest extraction rates (126,414 ind./y versus 3,133 ind./y for birds). Eighty eight percent of international trade records spatially overlapped with domestic trade, especially towards the north and across the coast but also in western inland areas. The distribution of domestic trade was broadly distributed along roads, suggesting that domestic trade does not depend on large markets in cities. Seventeen percent of domestic trade records overlapped with subsistence hunting, but the spatial distribution of this overlap covered a much larger area than between commercial uses. Domestic trade seems to respond to demand from rural more than urban communities. Our approach will be useful for understanding how IWU works at national scales in other parts of the world. This article is protected by copyright. All rights reserved

ACS Style

Ada Sánchez-Mercado; Marianne Asmüssen; Kathryn Rodriguez-Clark; Jon Paul Rodríguez; Wlodzimierz Jedrzejewski. Using spatial patterns in illegal wildlife uses to reveal connections between subsistence hunting and trade. Conservation Biology 2016, 30, 1222 -1232.

AMA Style

Ada Sánchez-Mercado, Marianne Asmüssen, Kathryn Rodriguez-Clark, Jon Paul Rodríguez, Wlodzimierz Jedrzejewski. Using spatial patterns in illegal wildlife uses to reveal connections between subsistence hunting and trade. Conservation Biology. 2016; 30 (6):1222-1232.

Chicago/Turabian Style

Ada Sánchez-Mercado; Marianne Asmüssen; Kathryn Rodriguez-Clark; Jon Paul Rodríguez; Wlodzimierz Jedrzejewski. 2016. "Using spatial patterns in illegal wildlife uses to reveal connections between subsistence hunting and trade." Conservation Biology 30, no. 6: 1222-1232.

Journal article
Published: 31 May 2014 in Biological Conservation
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Documenting changes in distribution is necessary for understanding species’ response to environmental changes, but data on species distributions are heterogeneous in accuracy and resolution. Combining different data sources and methodological approaches can fill gaps in knowledge about the dynamic processes driving changes in species-rich, but data-poor regions. We combined recent bird survey data from the Neotropical Biodiversity Mapping Initiative (NeoMaps) with historical distribution records to estimate potential changes in the distribution of eight species of Amazon parrots in Venezuela. Using environmental covariates and presence-only data from museum collections and the literature, we first used maximum likelihood to fit a species distribution model (SDM) estimating a historical maximum probability of occurrence for each species. We then used recent, NeoMaps survey data to build single-season occupancy models (OM) with the same environmental covariates, as well as with time- and effort-dependent detectability, resulting in estimates of the current probability of occurrence. We finally calculated the disagreement between predictions as a matrix of probability of change in the state of occurrence. Our results suggested negative changes for the only restricted, threatened species, Amazona barbadensis, which has been independently confirmed with field studies. Two of the three remaining widespread species that were detected, Amazona amazonica, Amazona ochrocephala, also had a high probability of negative changes in northern Venezuela, but results were not conclusive for Amazona farinosa. The four remaining species were undetected in recent field surveys; three of these were most probably absent from the survey locations (Amazona autumnalis, Amazona mercenaria and Amazona festiva), while a fourth (Amazona dufresniana) requires more intensive targeted sampling to estimate its current status. Our approach is unique in taking full advantage of available, but limited data, and in detecting a high probability of change even for rare and patchily-distributed species. However, it is presently limited to species meeting the strong assumptions required for maximum-likelihood estimation with presence-only data, including very high detectability and representative sampling of its historical distribution.

ACS Style

José R. Ferrer-Paris; Ada Sánchez-Mercado; Kathryn Rodriguez-Clark; Jon Paul Rodríguez; Gustavo A. Rodríguez. Using limited data to detect changes in species distributions: Insights from Amazon parrots in Venezuela. Biological Conservation 2014, 173, 133 -143.

AMA Style

José R. Ferrer-Paris, Ada Sánchez-Mercado, Kathryn Rodriguez-Clark, Jon Paul Rodríguez, Gustavo A. Rodríguez. Using limited data to detect changes in species distributions: Insights from Amazon parrots in Venezuela. Biological Conservation. 2014; 173 ():133-143.

Chicago/Turabian Style

José R. Ferrer-Paris; Ada Sánchez-Mercado; Kathryn Rodriguez-Clark; Jon Paul Rodríguez; Gustavo A. Rodríguez. 2014. "Using limited data to detect changes in species distributions: Insights from Amazon parrots in Venezuela." Biological Conservation 173, no. : 133-143.

Journal article
Published: 22 July 2013 in Revista de Biología Tropical
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The development of efficient sampling protocols is an essential prerequisite to evaluate and identify priority conservation areas. There are few protocols for fauna inventory and monitoring in wide geographical scales for the tropics, where the complexity of communities and high biodiversity levels, make the implementation of efficient protocols more difficult. We proposed here a simple strategy to optimize the capture of dung beetles, applied to sampling with baited traps and generalizable to other sampling methods. We analyzed data from eight transects sampled between 2006-2008 with the aim to develop an uniform sampling design, that allows to confidently estimate species richness, abundance and composition at wide geographical scales. We examined four characteristics of any sampling design that affect the effectiveness of the sampling effort: the number of traps, sampling duration, type and proportion of bait, and spatial arrangement of the traps along transects. We used species accumulation curves, rank-abundance plots, indicator species analysis, and multivariate correlograms. We captured 40 337 individuals (115 species/morphospecies of 23 genera). Most species were attracted by both dung and carrion, but two thirds had greater relative abundance in traps baited with human dung. Different aspects of the sampling design influenced each diversity attribute in different ways. To obtain reliable richness estimates, the number of traps was the most important aspect. Accurate abundance estimates were obtained when the sampling period was increased, while the spatial arrangement of traps was determinant to capture the species composition pattern. An optimum sampling strategy for accurate estimates of richness, abundance and diversity should: (1) set 50-70 traps to maximize the number of species detected, (2) get samples during 48-72 hours and set trap groups along the transect to reliably estimate species abundance, (3) set traps in groups of at least 10 traps to suitably record the local species composition, and (4) separate trap groups by a distance greater than 5-10km to avoid spatial autocorrelation. For the evaluation of other sampling protocols we recommend to, first, identify the elements of sampling design that could affect the sampled effort (the number of traps, sampling duration, type and proportion of bait) and their spatial distribution (spatial arrangement of the traps) and then, to evaluate how they affect richness, abundance and species composition estimates.

ACS Style

José Rafael Ferrer Paris; Ada Sánchez Mercado; Jon Paul Rodríguez. Optimización del muestreo de invertebrados tropicales: Un ejemplo con escarabajos coprófagos (Coleoptera: Scarabaeinae) en Venezuela. Revista de Biología Tropical 2013, 61, 1 .

AMA Style

José Rafael Ferrer Paris, Ada Sánchez Mercado, Jon Paul Rodríguez. Optimización del muestreo de invertebrados tropicales: Un ejemplo con escarabajos coprófagos (Coleoptera: Scarabaeinae) en Venezuela. Revista de Biología Tropical. 2013; 61 (1):1.

Chicago/Turabian Style

José Rafael Ferrer Paris; Ada Sánchez Mercado; Jon Paul Rodríguez. 2013. "Optimización del muestreo de invertebrados tropicales: Un ejemplo con escarabajos coprófagos (Coleoptera: Scarabaeinae) en Venezuela." Revista de Biología Tropical 61, no. 1: 1.

Research article
Published: 23 May 2013 in PLOS ONE
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We aggregated data on butterfly-host plant associations from existing sources in order to address the following questions: (1) is there a general correlation between host diversity and butterfly species richness?, (2) has the evolution of host plant use followed consistent patterns across butterfly lineages?, (3) what is the common ancestral host plant for all butterfly lineages? The compilation included 44,148 records from 5,152 butterfly species (28.6% of worldwide species of Papilionoidea) and 1,193 genera (66.3%). The overwhelming majority of butterflies use angiosperms as host plants. Fabales is used by most species (1,007 spp.) from all seven butterfly families and most subfamilies, Poales is the second most frequently used order, but is mostly restricted to two species-rich subfamilies: Hesperiinae (56.5% of all Hesperiidae), and Satyrinae (42.6% of all Nymphalidae). We found a significant and strong correlation between host plant diversity and butterfly species richness. A global test for congruence (Parafit test) was sensitive to uncertainty in the butterfly cladogram, and suggests a mixed system with congruent associations between Papilionidae and magnoliids, Hesperiidae and monocots, and the remaining subfamilies with the eudicots (fabids and malvids), but also numerous random associations. The congruent associations are also recovered as the most probable ancestral states in each node using maximum likelihood methods. The shift from basal groups to eudicots appears to be more likely than the other way around, with the only exception being a Satyrine-clade within the Nymphalidae that feed on monocots. Our analysis contributes to the visualization of the complex pattern of interactions at superfamily level and provides a context to discuss the timing of changes in host plant utilization that might have promoted diversification in some butterfly lineages.

ACS Style

José R. Ferrer-Paris; Ada Sánchez-Mercado; Ángel L. Viloria; John Donaldson. Congruence and Diversity of Butterfly-Host Plant Associations at Higher Taxonomic Levels. PLOS ONE 2013, 8, e63570 .

AMA Style

José R. Ferrer-Paris, Ada Sánchez-Mercado, Ángel L. Viloria, John Donaldson. Congruence and Diversity of Butterfly-Host Plant Associations at Higher Taxonomic Levels. PLOS ONE. 2013; 8 (5):e63570.

Chicago/Turabian Style

José R. Ferrer-Paris; Ada Sánchez-Mercado; Ángel L. Viloria; John Donaldson. 2013. "Congruence and Diversity of Butterfly-Host Plant Associations at Higher Taxonomic Levels." PLOS ONE 8, no. 5: e63570.

Journal article
Published: 01 March 2013 in Revista de Biología Tropical
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José Rafael Ferrer-Paris; Ada Sánchez-Mercado; Jon Paul Rodríguez. [Sampling optimization for tropical invertebrates: an example using dung beetles (Coleoptera: Scarabaeinae) in Venezuela]. Revista de Biología Tropical 2013, 61, 1 .

AMA Style

José Rafael Ferrer-Paris, Ada Sánchez-Mercado, Jon Paul Rodríguez. [Sampling optimization for tropical invertebrates: an example using dung beetles (Coleoptera: Scarabaeinae) in Venezuela]. Revista de Biología Tropical. 2013; 61 (1):1.

Chicago/Turabian Style

José Rafael Ferrer-Paris; Ada Sánchez-Mercado; Jon Paul Rodríguez. 2013. "[Sampling optimization for tropical invertebrates: an example using dung beetles (Coleoptera: Scarabaeinae) in Venezuela]." Revista de Biología Tropical 61, no. 1: 1.

Biodiversity research
Published: 08 October 2012 in Diversity and Distributions
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Aim To test a method for rapidly and reliably collecting species distribution and abundance data over large tropical areas [known as Neotropical Biodiversity Mapping Initiative (NeoMaps)], explicitly seeking to improve cost‐ and time‐efficiencies over existing methods (i.e. museum collections, literature), while strengthening local capacity for data collection. Location Venezuela. Methods We placed a grid over Venezuela (0.5 × 0.5 degree cells) and applied a stratified sampling design to select a minimum set of 25 cells spanning environmental and biogeographical variation. We implemented standardized field sampling protocols for birds, butterflies and dung beetles, along transects on environmental gradients (‘gradsects’). We compared species richness estimates from our field surveys at national, bioregional and cell scales to those calculated from data compiled from museum collections and the literature. We estimated the variance in richness, composition, relative abundance and diversity between gradsects that could be explained by environmental and biogeographical variables. We also estimated total survey effort and cost. Results In one field season, we covered 8% of the country and recorded 66% of all known Venezuelan dung beetles, 52% of Pierid butterflies and 37% of birds. Environmental variables explained 27–60% of variation in richness for all groups and 13–43% of variation in abundance and diversity in dung beetles and birds. Bioregional and environmental variables explained 43–58% of the variation in the dissimilarity matrix between transects for all groups. Main conclusions NeoMaps provides reliable estimates of richness, composition and relative abundance, required for rigorous monitoring and spatial prediction. NeoMaps requires a substantial investment, but is highly efficient, achieving survey goals for each group with 1‐month fieldwork and about US$ 1–8 per km2. Future work should focus on other advantages of this type of survey, including the ability to monitor the changes in relative abundance and turnover in species composition, and thus overall diversity patterns.

ACS Style

José R. Ferrer-Paris; Jon P. Rodríguez; Tatjana C. Good; Ada Y. Sánchez-Mercado; Kathryn M. Rodríguez-Clark; Gustavo A. Rodríguez; Angel Solís. Systematic, large-scale national biodiversity surveys: NeoMaps as a model for tropical regions. Diversity and Distributions 2012, 19, 215 -231.

AMA Style

José R. Ferrer-Paris, Jon P. Rodríguez, Tatjana C. Good, Ada Y. Sánchez-Mercado, Kathryn M. Rodríguez-Clark, Gustavo A. Rodríguez, Angel Solís. Systematic, large-scale national biodiversity surveys: NeoMaps as a model for tropical regions. Diversity and Distributions. 2012; 19 (2):215-231.

Chicago/Turabian Style

José R. Ferrer-Paris; Jon P. Rodríguez; Tatjana C. Good; Ada Y. Sánchez-Mercado; Kathryn M. Rodríguez-Clark; Gustavo A. Rodríguez; Angel Solís. 2012. "Systematic, large-scale national biodiversity surveys: NeoMaps as a model for tropical regions." Diversity and Distributions 19, no. 2: 215-231.

Journal article
Published: 01 June 2012 in The Wilson Journal of Ornithology
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Gustavo A. Rodríguez; Jon Paul Rodríguez; José Rafael Ferrer-Paris; Ada Sánchez-Mercado. A Nation-Wide Standardized Bird Survey Scheme for Venezuela. The Wilson Journal of Ornithology 2012, 124, 230 -244.

AMA Style

Gustavo A. Rodríguez, Jon Paul Rodríguez, José Rafael Ferrer-Paris, Ada Sánchez-Mercado. A Nation-Wide Standardized Bird Survey Scheme for Venezuela. The Wilson Journal of Ornithology. 2012; 124 (2):230-244.

Chicago/Turabian Style

Gustavo A. Rodríguez; Jon Paul Rodríguez; José Rafael Ferrer-Paris; Ada Sánchez-Mercado. 2012. "A Nation-Wide Standardized Bird Survey Scheme for Venezuela." The Wilson Journal of Ornithology 124, no. 2: 230-244.

Journal article
Published: 10 July 2008 in Oryx
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Worldwide, many large mammals are threatened by poaching. However, understanding the causes of poaching is difficult when both hunter and hunted are elusive. One alternative is to apply regression models to opportunistically-collected data but doing so without accounting for inherent biases may result in misleading conclusions. To demonstrate a straightforward method to account for such biases, and to guide further research on an elusive Vulnerable species, we visualized spatio-temporal poaching patterns in 844 Andean bear Tremarctos ornatus presence reports from the Cordillera de Mérida, Venezuela. To create maps of poaching risk we fitted two logistic regression models to a subset of 287 precisely georeferenced reports, one ignoring and one including spatial autocorrelation. Whereas the variance explained by both models was low, the second had better fit and predictive ability, and indicated that protected status had a significant positive effect on reducing poaching risk. Poaching risk increased at lower altitudes, where all indicators of human disturbance increased, although there was scant evidence that human-bear conflicts are a major direct trigger of poaching events. Because highest-risk areas were different from areas with most bear reports, we speculate that hunting may be driven by opportunistic encounters, rather than by purposeful searches in high-quality bear habitat. Further research comparing risk maps with bear abundance models and data on poaching behaviour will be invaluable for clarifying poaching causes and for identifying management strategies.

ACS Style

Ada Sánchez-Mercado; José R. Ferrer-Paris; Edgard Yerena; Shaenandhoa García-Rangel; Kathryn M. Rodríguez-Clark. Factors affecting poaching risk to Vulnerable Andean bears Tremarctos ornatus in the Cordillera de Mérida, Venezuela: space, parks and people. Oryx 2008, 42, 437 -447.

AMA Style

Ada Sánchez-Mercado, José R. Ferrer-Paris, Edgard Yerena, Shaenandhoa García-Rangel, Kathryn M. Rodríguez-Clark. Factors affecting poaching risk to Vulnerable Andean bears Tremarctos ornatus in the Cordillera de Mérida, Venezuela: space, parks and people. Oryx. 2008; 42 (3):437-447.

Chicago/Turabian Style

Ada Sánchez-Mercado; José R. Ferrer-Paris; Edgard Yerena; Shaenandhoa García-Rangel; Kathryn M. Rodríguez-Clark. 2008. "Factors affecting poaching risk to Vulnerable Andean bears Tremarctos ornatus in the Cordillera de Mérida, Venezuela: space, parks and people." Oryx 42, no. 3: 437-447.

Journal article
Published: 30 April 2006 in Biological Conservation
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Populations of threatened taxa in captivity within their natural ranges can make important contributions to conservation, but these may be compromised by the inappropriate application of population management goals developed in other contexts. We conducted demographic, genetic, and population viability analyses on the captive population of Andean bears (Tremarctos ornatus) in Venezuela to investigate the management of within-range captive populations in general, and to better integrate this population into the conservation of Andean bears in particular. We found that although the present population is very small and not internally self-sustaining, incorporation of confiscated wild individuals has resulted in a low average number of generations in captivity and low inbreeding, with moderate gene diversity and a high probability of future population persistence. However, past imports from extra-range populations have been from over-represented lineages of unknown origin, which have mixed with under-represented Venezuelan ones, reducing the future value of the Venezuelan population as a source for founder stock. Our analyses indicate that the rate of incorporation of wild recruits is a major factor influencing proxy measures of conservation value, and distinguishing within- from extra-range populations. This implies that, contrary to conventional wisdom, internal self-sustainability can be a misguided goal in within-range populations, which furthermore may not be suitable destinations for surplus animals from captive populations elsewhere.

ACS Style

Kathryn M. Rodríguez-Clark; Ada Sáncez-Mercado. Population management of threatened taxa in captivity within their natural ranges: Lessons from Andean bears (Tremarctos ornatus) in Venezuela. Biological Conservation 2006, 129, 134 -148.

AMA Style

Kathryn M. Rodríguez-Clark, Ada Sáncez-Mercado. Population management of threatened taxa in captivity within their natural ranges: Lessons from Andean bears (Tremarctos ornatus) in Venezuela. Biological Conservation. 2006; 129 (1):134-148.

Chicago/Turabian Style

Kathryn M. Rodríguez-Clark; Ada Sáncez-Mercado. 2006. "Population management of threatened taxa in captivity within their natural ranges: Lessons from Andean bears (Tremarctos ornatus) in Venezuela." Biological Conservation 129, no. 1: 134-148.

Dataset
Published: 01 September 2021
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Documenting changes in distribution is necessary for understanding species' response to environmental changes, but data on species distributions are heterogeneous in accuracy and resolution. Combining different data sources and methodological approaches can fill gaps in knowledge about the dynamic processes driving changes in species-rich, but data-poor regions. We combined recent bird survey data from the Neotropical Biodiversity Mapping Initiative (NeoMaps) with historical distribution records to estimate potential changes in the distribution of eight species of Amazon parrots in Venezuela. Using environmental covariates and presence-only data from museum collections and the literature, we first used maximum likelihood to fit a species distribution model (SDM) estimating a historical maximum probability of occurrence for each species. We then used recent, NeoMaps survey data to build single-season occupancy models (OM) with the same environmental covariates, as well as with time- and effort-dependent detectability, resulting in estimates of the current probability of occurrence. We finally calculated the disagreement between predictions as a matrix of probability of change in the state of occurrence. Our results suggested negative changes for the only restricted, threatened species, Amazona barbadensis, which has been independently confirmed with field studies. Two of the three remaining widespread species that were detected, Amazona amazonica, Amazona ochrocephala, also had a high probability of negative changes in northern Venezuela, but results were not conclusive for Amazona farinosa. The four remaining species were undetected in recent field surveys; three of these were most probably absent from the survey locations (Amazona autumnalis, Amazona mercenaria and Amazona festiva), while a fourth (Amazona dufresniana) requires more intensive targeted sampling to estimate its current status. Our approach is unique in taking full advantage of available, but limited data, and in detecting a high probability of change even for rare and patchily-distributed species. However, it is presently limited to species meeting the strong assumptions required for maximum-likelihood estimation with presence-only data, including very high detectability and representative sampling of its historical distribution.

ACS Style

José R Ferrer-Paris; Ada Sánchez-Mercado; Jon Paul Rodríguez; Gustavo A Rodríguez. Detection histories for eight species of Amazona parrots in Venezuela during the NeoMaps bird surveys in 2010, supplement to: Ferrer-Paris, José R; Sánchez-Mercado, Ada; Rodríguez-Clark, Kathryn M; Rodríguez, Jon Paul; Rodríguez, Gustavo A (2013): Using limited data to detect changes in species distributions: Insights from Amazon parrots in Venezuela. Biological Conservation, 173, 133-143. 2021, 1 .

AMA Style

José R Ferrer-Paris, Ada Sánchez-Mercado, Jon Paul Rodríguez, Gustavo A Rodríguez. Detection histories for eight species of Amazona parrots in Venezuela during the NeoMaps bird surveys in 2010, supplement to: Ferrer-Paris, José R; Sánchez-Mercado, Ada; Rodríguez-Clark, Kathryn M; Rodríguez, Jon Paul; Rodríguez, Gustavo A (2013): Using limited data to detect changes in species distributions: Insights from Amazon parrots in Venezuela. Biological Conservation, 173, 133-143. . 2021; ():1.

Chicago/Turabian Style

José R Ferrer-Paris; Ada Sánchez-Mercado; Jon Paul Rodríguez; Gustavo A Rodríguez. 2021. "Detection histories for eight species of Amazona parrots in Venezuela during the NeoMaps bird surveys in 2010, supplement to: Ferrer-Paris, José R; Sánchez-Mercado, Ada; Rodríguez-Clark, Kathryn M; Rodríguez, Jon Paul; Rodríguez, Gustavo A (2013): Using limited data to detect changes in species distributions: Insights from Amazon parrots in Venezuela. Biological Conservation, 173, 133-143." , no. : 1.