RESUMO
The avifauna of South America is one of the most widely studied groups of vertebrates. However, certain species, such as the Andean Ibis (Theristicus branickii), have received limited attention regarding their ecological patterns, biology, current distribution, and environmental requirements. This study analyzed observation data from the Global Biodiversity Information Facility (GBIF) on the Andean Ibis in four countries to identify and understand critical variables that determine the species' presence, assess the proportion of its habitat within protected areas and identify possible threats to the species. Additionally, this study considered environmental and ecological variables to model ecological niches using the maximum entropy approach in MaxEnt to map the suitable habitat of the species. The findings revealed the extent of suitable Andean Ibis habitats in Ecuador, Peru, Bolivia and Chile. The variables that most determined the presence of the species were: altitude (36.57%), distance to lakes (23.29%) and ecological isothermality (13.34%). The distribution area of the Andean Ibis totaled 300,095.00 km2, spanning both sides of the Andean mountains range. Human activities have left a significant impact on the Andean Ibis habitat, with 48% of this area impacted by the human footprint and only 10% of the territory falling within protected areas designated by the respective countries. The results of this study show that the Andean Ibis presents characteristics of a specialist species due to its adaptation to the climate conditions of the plateau and highlands, including low temperatures, herbaceous vegetation and the presence of water bodies. The species is distributed in disconnected Andean landscape areas, whose functionality could be compromised by increased human activities. Complementary studies will be necessary to understand the ecological role and effectiveness of protected areas for conserving the species.
Assuntos
Aves , Animais , Humanos , Peru , Equador , Bolívia , ChileRESUMO
The data set comes from a tree inventory conducted in an evergreen forest fragment (dominated by Laureliopsis philippiana and Eucryphia cordifolia) and four fragments dominated by Nothofagus obliqua. The forests are located in an agroforestry matrix landscape of the Coastal Mountain Range of the Chilean Lake District. The data collection was carried out using line transect sampling, which was traced through the core of each fragment oriented towards its longest axis. Data provide taxonomic identity, diameter at breast height (DBP), overstory canopy cover, condition (e.g. live or snag), some height samples, and the estimate of the vertical stratification (e.g. canopy or understory) of 462 trees belonging to 19 species. The data also shows a record of 50 woody debris. The geographical location of each forest fragments is also included. Inventories are fundamental for knowledge of species diversity and provide the foundation for more complex analytical studies, such as the distribution of plant assemblages in the landscape; determine the conservation status of species, and research into biogeographical or macro-ecological areas of interest.
RESUMO
BACKGROUND: The effects of global climate change on species inhabiting marine ecosystems are of growing concern, especially for endemic species that are sensitive due to restricted distribution. One method employed for determining the effects of climate change on the distribution of these organisms is species distribution modeling. METHODS: We generated a model to evaluate the potential geographic distribution and breeding distribution of the Peruvian pelican (Pelecanus thagus). Based on maximum entropy modeling (MaxEnt), we identified the environmental factors that currently affect its geographic distribution and breeding. Then we predicted its future distribution range under two climate change scenarios: moderate (rcp 2.6) and severe (rcp 8.5). RESULTS: The mean daytime temperature range and marine primary productivity explain the current potential distribution and breeding of the pelican. Under the future climate change scenarios, the spatial distribution of the pelican is predicted to slightly change. While the breeding distribution of the pelican can benefit in the moderate scenario, it is predicted to decrease (near -20 %) in the severe scenario. DISCUSSION: The current potential geographic distribution of the pelican is influenced to a large extent by thermal conditions and primary productivity. Under the moderate scenario, a slight increase in pelican breeding distribution is predicted. This increase in habitable area is explained by the climatic conditions in southern Chile, and those climatic conditions will likely be similar to the current conditions of the central coast of Chile. We predict that the coasts of southern Chile will constitute an important refuge for the conservation of the Peruvian pelican under future climate change scenarios.