Exploiting virtual globes for ecology and conservation in the Digital Earth era

Letter.Peer Reviewe

Assessing species habitat using Google Street View: A case study of cliff-nesting vultures

The assessment of a species' habitat is a crucial issue in ecology and conservation. While the collection of habitat data has been boosted by the availability of remote sensing technologies, certain habitat types have yet to be collected through costly, on-ground surveys, limiting study over large areas. Cliffs are ecosystems that provide habitat for a rich biodiversity, especially raptors. Because of their principally vertical structure, however, cliffs are not easy to study by remote sensing technologies, posing a challenge for many researches and managers working with cliff-related biodiversity. We explore the feasibility of Google Street View, a freely available on-line tool, to remotely identify and assess the nesting habitat of two cliff-nesting vultures (the griffon vulture and the globally endangered Egyptian vulture) in northwestern Spain. Two main usefulness of Google Street View to ecologists and conservation biologists were evaluated: i) remotely identifying a species' potential habitat and ii) extracting fine-scale habitat information. Google Street View imagery covered 49% (1,907 km) of the roads of our study area (7,000 km2). The potential visibility covered by on-ground surveys was significantly greater (mean: 97.4%) than that of Google Street View (48.1%). However, incorporating Google Street View to the vulture's habitat survey would save, on average, 36% in time and 49.5% in funds with respect to the on-ground survey only. The ability of Google Street View to identify cliffs (overall accuracy = 100%) outperformed the classification maps derived from digital elevation models (DEMs) (62-95%). Nonetheless, high-performance DEM maps may be useful to compensate Google Street View coverage limitations. Through Google Street View we could examine 66% of the vultures' nesting-cliffs existing in the study area (n = 148): 64% from griffon vultures and 65% from Egyptian vultures. It also allowed us the extraction of fine-scale features of cliffs. This World Wide Web-based methodology may be a useful, complementary tool to remotely map and assess the potential habitat of cliff-dependent biodiversity over large geographic areas, saving survey-related costs.PMT was supported by a postdoctoral grant funded by Junta de Comunidades de Castilla-La Mancha and Fondo Social Europeo.Peer Reviewe

Nested species- rich networks of scavenging vertebrates support high levels of interspecific competition

et al.Disentangling the processes that shape the organization of ecological assemblages and its implications for species coexistence is one of the foremost challenges of ecology. Although insightful advances have recently related community composition and structure with species coexistence in mutualistic and antagonistic networks, little is known regarding other species assemblages, such as those of scavengers exploiting carrion. Here we studied seven assemblages of scavengers feeding on ungulate carcasses in mainland Spain. We used dynamical models to investigate if community composition, species richness and structure (nestedness) affect species coexistence at carcasses. Scavenging networks showed a nested pattern in sites where highly efficient, obligate scavengers (i.e., vultures) were present and a non- nested pattern everywhere else. Griffon Vulture ( Gyps fulvus ) and certain meso- facultative mammalian scavengers (i.e., red fox, Vulpes vulpes, and stone marten, Martes foina ) were the main species contributing to nestedness. Assemblages with vultures were also the richest ones in species. Nested species- rich assemblages with vulture presence were associated with high carcass consumption rates, indicating higher interspecific competition at the local scale. However, the proportion of species stopping the consumption of carrion (as derived from the competitive dynamic model) stabilized at high richness and nestedness levels. This suggests that high species richness and nestedness may characterize scavenging networks that are robust to high levels of interspecific competition for carrion. Some facilitative interactions driven by vultures and major facultative scavengers could be behind these observations. Our findings are relevant for understanding species' coexistence in highly competitive systems.E. Sebastián-González and P. R. Guimarães benefited from FAPESP Research Foundation grants numbers 2011/17968-2 and 2009/054422-8, respectively; E. Sebastián-González is currently funded under the NSF grant NSF Award #1345247, M. Moleón by a postdoctoral grant from the Spanish Ministry of Education (Plan Nacional de I+D+I 2008-2011), J. P. Gibert by an Other Fellowship and SBS Special Funds (U. of N.), and P. Mateo-Tomás by a postdoctoral grant of the Junta de Comunidades de Castilla- La Mancha and Fondo Social Europeo. The study was supported by the Spanish Ministry of Science and Innovation through projects 23/2007 ICTS- RBD, CGL2009-12753-C02-02, and CGL2012-40013-C02-02, FEDER funds, the Generalitat Valenciana through project ACOMP/2012/147, and the Junta de Andalucía through project RNM-1925.Peer Reviewe

Nested species-rich networks of scavenging vertebrates support high levels of interspecific competition

Disentangling the processes that shape the organization of ecological assemblages and its implications for species coexistence is one of the foremost challenges of ecology. Although insightful advances have recently related community composition and structure with species coexistence in mutualistic and antagonistic networks, little is known regarding other species assemblages, such as those of scavengers exploiting carrion. Here we studied seven assemblages of scavengers feeding on ungulate carcasses in mainland Spain. We used dynamical models to investigate if community composition, species richness and structure (nestedness) affect species coexistence at carcasses. Scavenging networks showed a nested pattern in sites where highly efficient, obligate scavengers (i.e., vultures) were present and a non- nested pattern everywhere else. Griffon Vulture ( Gyps fulvus ) and certain meso- facultative mammalian scavengers (i.e., red fox, Vulpes vulpes, and stone marten, Martes foina ) were the main species contributing to nestedness. Assemblages with vultures were also the richest ones in species. Nested species- rich assemblages with vulture presence were associated with high carcass consumption rates, indicating higher interspecific competition at the local scale. However, the proportion of species stopping the consumption of carrion (as derived from the competitive dynamic model) stabilized at high richness and nestedness levels. This suggests that high species richness and nestedness may characterize scavenging networks that are robust to high levels of interspecific competition for carrion. Some facilitative interactions driven by vultures and major facultative scavengers could be behind these observations. Our findings are relevant for understanding species' coexistence in highly competitive systemsE. Sebastián- González and P. R. Guimarães benefited from FAPESP Research Foundation grants numbers 2011/17968- 2 and 2009/054422- 8, respectively; E. Sebastián- González is currently funded under the NSF grant NSF Award #1345247, M. Moleón by a postdoctoral grant from the Spanish Ministry of Education (Plan Nacional de I+D+I 2008- 2011), J. P. Gibert by an Other Fellowship and SBS Special Funds (U. of N.), and P. Mateo-Tomás by a postdoctoral grant of the Junta de Comunidades de Castilla-La Mancha and Fondo Social Europeo. The study was supported by the Spanish Ministry of Science and Innovation through projects 23/2007 ICTS- RBD, CGL2009- 12753- C02- 02, and CGL2012- 40013- C02- 02, FEDER funds, the Generalitat Valenciana through project ACOMP/2012/147, and the Junta de Andalucía through project RNM- 192

Análisis del retardo cenital trofosférico estimado desde observaciones GNSS en América Latina

La señal GNSS (Global Navigation satellite System) es afectada en su recorrido, desde el satélite al receptor instalado en tierra, de un retardo conocido como retardo cenital troposférico, ZTD (Zenith Tropospheric Delay o Zenith Total Delay). Este retardo es variable en el tiempo y depende del sitio donde se encuentra el receptor. Su variabilidad es ocasionada por el vapor de agua presente en la atmósfera, el cual tiene una gran variabilidad tanto espacial como temporal. El ZTD es un parámetro que se estima en el procesamiento de las observaciones GNSS, como un elemento correctivo necesario para obtener coordenadas con precisión centimétrica, por lo cual los softwares de procesamiento lo calculan dentro del modelo de estimación de incógnitas. Desde SIRGAS (Sistema de Referencia Geocéntrico para las Américas), el ZTD es estimado en el cálculo que se realiza oficialmente desde los centros de procesamiento, en paquetes semanales, con un intervalo para este parámetro de 1 hora

Productos troposféricos de SIRGAS. ¿Qué son? ¿Para qué sirven? Estado al 2020 y perspectivas futuras

El vapor de agua en la Troposfera es uno de los componentes menos comprendidos y escasamente descriptos de la Atmósfera terrestre. La medición del mismo se realiza tradicionalmente mediante radiosondas (técnica costosa, dado que se pierde en cada lanzamiento). Motivó nuestra investigación (iniciada hace más de 10 años atrás) el interés por buscar una técnica alternativa mediante el retardo que experimenta la señal GNSS, que permitiese mejorar su determinación y variabilidad espacio-temporal, sin necesidad de invertir significativos costos. Esta investigación la llevamos a cabo dentro de SIRGAS (Sistema de Referencia Geocéntrico para las Américas) y tiene como objetivo sumar nuevos productos desde la red de estaciones GNSS de monitoreo continuo SIRGAS-CON

Sismos en Ridgecrest, California. Cálculo de desplazamientos sísmicos mediante GNSS y su comparación con instrumentos sismológicos

Comunicación científica en formato E-PÓSTER, realizada en las III Jornadas Internacionales de Investigación, Ciencia y Universidad y las XII Jornadas de Investigación UMaza, en el Bloque de comunicaciones científicas: "CIENCIAS DE LA TIERRA", el mismo fue moderado por el Lic. HÉCTOR CISNERO. Las jornadas se llevaron adelante desde 19 al 23 de octubre del 2020 en formato totalmente virtual bajo plataforma Zoom y fueron transmitidas por el canal YouTube de la UMaza y el Facebook del Área de Ciencia y Técnica UMaza (Somos Ciencia y Técnica UMaza)

Análisis meteorológico regional, influencia del fenómeno El Niño y La Niña. Anomalías de humedad ¿Pandemia o coincidencia?

Comunicación científica en formato E-PÓSTER, realizada en las III Jornadas Internacionales de Investigación, Ciencia y Universidad y las XII Jornadas de Investigación UMaza, en el Bloque de comunicaciones científicas: "GEOTECNOLOGÍAS Y AMBIENTE", el mismo fue moderado por el Lic. HÉCTOR CISNERO. Las jornadas se llevaron adelante desde 19 al 23 de octubre del 2020 en formato totalmente virtual bajo plataforma Zoom y fueron transmitidas por el canal YouTube de la UMaza y el Facebook del Área de Ciencia y Técnica UMaza (Somos Ciencia y Técnica UMaza)

Habitat selection and diet of Western Capercaillie

P. 260-272Ecological features and conservation requirements of populations at the latitudinal limits of a species’ geographical range frequently differ from those in other parts of the range. Identifying such differences is key to implementing effective conservation strategies for threatened range-edge populations especially, in the context of rapid global warming, at the lower-latitude range edge. We studied habitat selection and diet of the endangered Cantabrian Capercaillie Tetrao urogallus cantabricus in a recently discovered population at the southernmost edge of the sub-species’ range. This is the only Western Capercaillie population in the Mediterranean biogeographical region. We combined non-systematic surveys based on questionnaires, reports and field sampling with data from radiotracking to assess habitat selection. Diet was surveyed by micro-histological methods from droppings collected in the new population, which inhabits Pyrenean Oak Quercus pyrenaica forests and Scots Pine Pinus sylvestris plantations, and in two Cantabrian populations inhabiting Eurosiberian forests. Capercaillie preferred large (> 500 ha) and medium-sized (100–500 ha) Pyrenean Oak forest fragments and large Scots Pine plantations. Forest fragments smaller than 100 ha and non-forested habitats were always avoided. Diet differed markedly between Mediterranean and Eurosiberian populations. Bilberry Vaccinium myrtillus is common in the diet of most Capercaillie populations but was scarce in the study area and so was rare in the diet of the new population. Instead, Rockrose Halimium lasianthum was described for the first time as a major food resource for the Capercaillie and was consumed in autumn and winter. Pine needles were also heavily consumed in winter. We document for the first time the strong preference of Capercaillie for Pyrenean Oak forests and a moderately high consumption of the leaves, buds and acorns of this tree species throughout the year. Habitat selection and diet of this Mediterranean population differ from those of the core Cantabrian and other populations. Our results suggest a wider environmental tolerance (phenotypic plasticity) in the species than previously recognized. We advocate specific protection for this unique range-edge Capercaillie population and its Pyrenean Oak forest habitatS

Aporte al conocimiento de la estructura interna de la tierra a partir de observaciones GNSS

Se ha podido probar que los receptores satelitales, pueden observar la llegada de ondas superficiales y permiten conocer rápidamente el desplazamiento o deformación co-sísmica. En este trabajo se plantea la obtención de curvas de dispersión, que permiten conocer las velocidades a las que se transmiten las ondas superficiales a partir de observaciones GNSS