Alberto Yanosky - Academia.edu (original) (raw)

Papers by Alberto Yanosky

Global Biodiversity, 2018

Ibis, May 9, 2023

Grasslands are globally threatened and their biodiversity, including grassland birds, is declinin... more Grasslands are globally threatened and their biodiversity, including grassland birds, is declining markedly. To inform grassland bird conservation globally, we systematically reviewed threats and conservation actions for grassland birds, extracting data from 528 papers. Across the 10 primary grassland regions of the globe, agriculture was the most frequently or joint most frequently reported threat in nine regions (reported as a threat in 73% of publications); hunting was the most frequently reported threat in the remaining region. Natural system modifications (reported as a threat in 32% of publications) and climate change and severe weather (24%) were less frequently reported threats compared with agriculture. The types of threat from agriculture varied regionally, but the most pervasive were livestock farming and ranching (reported in 58% of publications where agriculture was a primary threat) and non‐timber cropping (43%). Most agricultural threats relate to intensification, but agricultural abandonment, typically the cessation of grazing, sometimes accompanied by tree planting/succession, poses an emerging threat to some grassland birds (reported in 32% of publications where agriculture was a primary threat). The most frequent conservation actions implemented to date include land/water management and protection, and species‐specific management actions. Authors of reviewed publications in almost all regions recommend more land/water management, followed by calls for further land/water protection. The parlous state of grassland birds globally suggests that existing conservation actions for grasslands are inadequate. Furthermore, our review suggests that these should be primarily targeted at reversing the negative impacts of agriculture, in particular livestock farming and cropping.

Ciencias Ambientales, Jul 1, 2020

Conservation Letters, 2022

International funding is increasingly important in supporting conservation in mega‐biodiverse cou... more International funding is increasingly important in supporting conservation in mega‐biodiverse countries. However, it remains unclear which donors invest in which conservation objectives and where, making it difficult to identify gaps and key actors to influence. Here we identified 1947 foreign‐aided conservation projects in South America's major deforestation frontiers and summarized their objectives and interventions over time and space. We found that conserving nature for its own sake and for ecosystem services remained key objectives, but the types of interventions varied considerably over time. Geographically, international conservation prioritized moist forests over drier biomes, despite equally high deforestation risk. Different donor groups emphasized specific objectives and interventions that reflected socioecological links (e.g., bird migration, colonial history) between donating and receiving regions, as well as the donors’ values (e.g., iconic/endangered species, human rights). These telecoupled patterns provide both opportunities and barriers for conservation and have implications for conservation prioritization strategies.

Extensionismo, innovación y transferencia tecnológica, Mar 28, 2016

Transactions of The Royal Society of Tropical Medicine and Hygiene, Aug 4, 2022

Saint Louis encephalitis virus (SLEV), West Nile virus (WNV) and Ilheus virus (ILHV) are flavivir... more Saint Louis encephalitis virus (SLEV), West Nile virus (WNV) and Ilheus virus (ILHV) are flaviviruses maintained by enzootic transmission networks between mosquitoes and birds. They have been detected in South America, with no records for Paraguay. We detected the presence of neutralizing antibodies for SLEV, WNV and ILHV in free-ranging birds collected in Paraguay (2016–2018). Four positive samples were detected in resident birds: one SLEV (rufous-bellied thrush), one WNV (barred antshrike) and two ILHV (white-tipped dove and shiny cowbird). These results bring new information about enzootic activity of flaviviruses in Paraguay.

John Wiley & Sons, Ltd eBooks, Jul 12, 2013

Diversity and Distributions

Aim Land-use change and overexploitation are major threats to biodiversity, and climate change wi... more Aim Land-use change and overexploitation are major threats to biodiversity, and climate change will exert additional pressure in the 21st century. Although there are strong interactions between these threats, our understanding of the synergistic and compensatory effects on threatened species' range geography remains limited. Our aim was to disentangle the impact of habitat loss, hunting and climate change on species, using the example of the endangered Chacoan peccary (Catagonus wagneri). Location Gran Chaco ecoregion in South America. Methods Using a large occurrence database, we integrated a time-calibrated species distribution model with a hunting pressure model to reconstruct changes in the distribution of suitable peccary habitat between 1985 and 2015. We then used partitioning analysis to attribute the relative contribution of habitat change to land-use conversion, climate change and varying hunting pressure. Results Our results reveal widespread habitat deterioration, with only 11% of the habitat found in 2015 considered suitable and safe. Hunting pressure was the strongest single threat, yet most habitat deterioration (58%) was due to the combined, rather than individual, effects of the three drivers we assessed. Climate change would have led to a compensatory effect, increasing suitable habitat area, yet this effect was negated by the strongly negative and interacting threats of land-use change and hunting. Main Conclusions Our study reveals the central role of overexploitation, which is often neglected in biogeographic assessments, and suggests that addressing overexploitation has huge potential for increasing species' adaptive capacity in the face of climate and land-use change. More generally, we highlight the importance of jointly assessing extinction drivers to understand how species might fare in the 21st century. Here, we provide a simple and transferable framework to determine the separate and joint effects of three main drivers of biodiversity loss.

Revista Latinoamericana de Herpetología

Gymnophthalmidae is a highly diverse family of small to medium sized South American lizards. In P... more Gymnophthalmidae is a highly diverse family of small to medium sized South American lizards. In Paraguay, seven species are currently known. Among these, Colobosaura modesta and Micrablepharus maximiliani are two poorly sampled species in the country: C. modesta was only recorded in two localities in Amambay and San Pedro Departments, whilst M. maximiliani was recorded in Central, Cordillera, Paraguarí and San Pedro Departments. During two field surveys in 2022 we captured one C. modesta and three M. maximiliani individuals. The C. modesta record is 134.7 km west from the nearest known locality, and it is the third confirmed locality in the country, the first in the Concepción Department and the first associated with the Humid Chaco. The M. maximiliani records are 81, 131 and 137 km north from the nearest known locality and are the first records from Concepción and Amambay Departments. We provide habitat characterization for where the lizards were found and discuss their conservatio...

The Atlantic forest of …, 2003

... Page 358. 334 PARAGUAY shared with Brazil to build the largest hydroelectric dam in the world... more ... Page 358. 334 PARAGUAY shared with Brazil to build the largest hydroelectric dam in the world. ... It comprises one representative each from the national commissions of Paraguay, Brazil, and Atgentina, plus a representative of the WWF and one from the IUCN. ...

ABSTRACT During the last 30 years, Paraguay underwent massive changes in the forest cover. Change... more ABSTRACT During the last 30 years, Paraguay underwent massive changes in the forest cover. Changes include the removal of the majority of the interior Atlantic Forest, an ecosystem with the highest levels of recorded biodiversity. This study quantified three decades of forest cover (FC) change in Paraguay using Landsat data. To assess FC change between the 1990s and 2000s, wall-to-wall mapping was performed, using data from Landsat TM and ETM+ instruments. Multispectral and multitemporal data were integrated into an unsupervised clustering process. Procedures were developed and implemented automatically to assign meaningful class labels to individual spectral clusters, substantially reducing human input. The accuracy assessment on the thematic map of FC in the 2000s was performed by examining aerial photos and the fine-resolution imagery. Overall accuracy on sampled populations was 0.9512 on average at a 95% confidence level. It indicates that the method used in this study is highly reliable in dealing both with data acquired at different times and with data from different Landsat instruments. Because of the differences in spatial and spectral-resolution between Landsat MSS and TM data, FC change between the 1970s and 1990s was estimated by assessing FC from each epoch using a different approach. FC for the 1970s was obtained by applying a statistical sampling method to the MSS imagery. Ecoregion-based stratified systematic sampling was utilized to select samples in every spatial interval of 0.15 degree in both the latitude and longitude directions. This method yielded 342 samples within the Atlantic Forest region. Each of 9 MSS pixels in individual samples was interpreted as forest or non-forest, which allowed the calculation of the percentage of FC within a given sample. When the method was applied to TM imagery for 1990s, the two methods, mapping and sampling, yielded almost identical results for the 1990 epoch. FC change between the 1970s and 1990s was calculated by differencing FC between the two epochs. The results show that the extent and spatial patterns of FC change in two main ecoregions, the Chaco and Atlantic Forest are considerably different. Between the 1990s and 2000s, 6.42% of the initial 134,400 km2 of the Chaco was lost, while the initial 34,800 km2 of the Atlantic forest was reduced by 38.9%. Within the Atlantic Forest region, the total area of 85,500 km2 was forested by 73.4% in the 1970s. The forest area was reduced by 40.7% during the 1990s. By the 2000s, only 24.8% of the total region was forested. Although most protected areas experienced little change within their borders, buffer zones were deforested at an alarming rate. For instance, a well-managed reserve, Mbaracayu National park suffered from 40.0% of the initial forest loss from 400 km2 to 240 km2 in a 5 km buffer zone between the 1990s and 2000s.

Archivos De Zootecnia, 1995