113 research outputs found

    Extensive sheep grazing is associated with trends in steppe birds in Spain: recommendations for the Common Agricultural Policy

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    Iberian natural steppes have traditionally been used for extensive sheep grazing, which has been noted to be positively associated with steppe bird abundance and diversity. Sheep numbers in Spain, which harbors the largest European populations of many steppe bird species, decreased by 9.2 million (37.3%) between 1992 and 2020. Steppe birds in Spain have faced dramatic declines during the same period, but there is a lack of knowledge about the potential association between sheep and open-habitat bird declines. We used sheep data from the Spanish Ministry of Agriculture and bird data (1998–2018) from the Spanish Common Bird Monitoring Program to assess the association at the Spanish scale between sheep decline and the Farmland Bird Index (FBI) and the Natural Shrub-steppe Bird Index (SBI). We also used an independent dataset on population trends of the Dupont’s Lark (Chersophilus duponti) to assess the relationship between sheep numbers and the decline of this threatened steppe specialist passerine in Spain, whose European population is restricted to Iberian natural steppes. To test for a spurious relationship between temporal series, variables were tested for cointegration. After confirming cointegration, we found a strong positive relationship between sheep abundance and the trends of the FBI and SBI indices during the period 1998–2018. The association between sheep abundance and trends of the Dupont’s Lark (2004–2015) was positive although it was not statistically significant. Although the main causes of decline of farmland and steppe birds are mainly related to agricultural intensification and land use changes, the correlation found, using two independent cointegrated datasets, between the reduction in farmland and shrub-steppe birds and sheep numbers at the country scale suggests that the decline of steppe birds in Spain may be also associated with the decline in sheep numbers. This agrees with previous studies that found a positive relationship between intermediate levels of sheep grazing and steppe bird abundance in Iberian steppes. Further research (e.g. experimental studies) is needed to corroborate our study and identify the most appropriate level of grazing intensity for protecting the most farmland and shrub-steppe birds. Our results suggest that the promotion of extensive grazing should be considered as a key factor in future Common Agricultural Policy reforms and conservation programmes to protect steppe birds.This is a contribution to the Excellence Network Remedinal 3CM (S2013/MAE2719), supported by Comunidad de Madrid and to the LIFE Ricotí (ES-LIFE15/NAT/ES/000802) and LIFE Connect Ricotí (ES-LIFE20/NAT/ES/000133) projects, supported by the European Commission

    Uso ganadero y diversidad de pastizales: relaciones con la disponibilidad y el movimiento de propágulos

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    Tesis doctoral inédita de la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Ecología. Fecha de lectura: 28-04-200

    Dispersión de semillas por adhesión en pastizales mediterráneos: una aproximación experimental

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    Wind farms affect the occurrence, abundance and population trends of small passerine birds: The case of the Dupont's lark

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    "This is the peer reviewed version of the following article: Journal of Applied Ecology 55.4 (2018): 2033-2042, which has been published in final form at https://doi.org/10.1111/1365-2664.13107. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited"The assessment of the effects of wind farms on bird populations is commonly based on collision fatality records. This could undervalue the effect of wind farms on small-sized birds. We evaluate the effect of wind turbines on occurrence, abundance and population trends of a threatened small passerine species, the Dupont's lark Chersophilus duponti. To our knowledge, this is one of the first studies addressing the effect of wind farms on population trends using time-series data from multiple wind farms. We estimated population trends by fitting a switching linear trend model with the software trim (Trend & Indices for Monitoring data). We used multiannual data surveys of five populations in the presence of wind farms and nine in their absence (2008–2016 period). Furthermore, we fitted a logistic and a negative binomial regression model to test the effect of wind farm proximity on species occurrence and abundance in 2016, respectively. We incorporated local connectivity and habitat availability estimates in both models as predictors. Results showed a negative trend overall, but that was significantly more regressive in the presence of wind farms: 21.0% vs. 5.8% average annual decline in the absence of wind farms. Dupont's lark occurrence and abundance in 2016 were negatively affected by measures of population isolation and positively affected by the distance to wind farms. These results highlight the negative effect of isolation and wind farm proximity on Dupont's lark population parameters. Taking into account the metapopulation structure exhibited by the species in the study area, this work established a 4.5-km threshold distance from wind farms, beyond which Dupont's lark populations should be unaffected. Synthesis and applications. This work highlights the negative impact of wind farms on small-sized birds and provides a 4.5-km threshold distance that should be taken into account in the design of future wind energy projects. Moreover, we suggest an analytical approach based on population trends, species abundance and occurrence variation in relation to wind farms, useful for the assessment of wind farm impacts on small-sized birdsEuropean Comission, Grant/Award Number: Life Ricotí (LIFE15-NAT-ES-000802); Excellence Network Remedinal 3CM (S2013/MAE−2719); Fundación Patrimonio Natural de Castilla y León; Biodiversity Foundation - Ministry of Agriculture, Food and Environment; Fundación BBVA, BBVARicotí-project; European Social Fund for the Youth Employment Initiativ

    Alondra ricotí – Chersophilus duponti (Vieillot, 1820)

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    Aves - Orden Passeriformes - Familia Alaudidae en la Enciclopedia Virtual de Vertebrados Españoles, http://www.vertebradosibericos.org/.A comprehensive review of the natural history of the Dupont’s Lark Chersophilus duponti in Spain.Peer reviewe

    Crops modify habitat quality beyond their limits

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    Edge effect is a strong driver of change in fragmented landscapes. In the last few decades, agricultural land-use intensity at field scale has increased and, consequently, the edges between crops and natural vegetation matrix have sharpened. Interspersed crops produce now negative effects not only by direct habitat destruction, but also by inputs of agrochemicals that may spread their effects on the surroundings. These processes are taking place worryingly in steppe habitats in Iberian Peninsula where the high diversity of bird communities and other taxa they hold is at risk. The aims of this study were to evaluate the edge effect of crops on i) the microhabitat quality of a natural landscape matrix and ii) the space use of a threatened habitat-specialist steppe bird, the Dupont's lark (Chersophilus duponti). We carried out microhabitat sampling and bird surveys within and around crops interspersed in a typical Iberian shrub-steppe matrix during spring and autumn 2016 and spring 2017. Microhabitat quality was measured by sampling vegetation structure and arthropod biomass (as proxy of food availability) within and at increasing distances (1, 10 and 50 m) to seven crops. The intensity of space use by the Dupont's lark was estimated applying a Kernel density function on the spatial point pattern of the males’ territories. Vegetation structure variables were summarized by Principal Components Analysis. Linear Mixed Models and model averaging were used to test for effects of distance to crop on microhabitat quality and space use by the Dupont's lark. Distance to crop significantly affected microhabitat quality. A patchy structure of herbaceous and shrub was found outside crops in all sampling dates, with more shrub cover and less herbaceous cover as the distance to crops increased. Biomass of hypogeous arthropods significantly decreased when the distance to crops was lower than 50 m. The intensity of space use by Dupont's lark varied according to the sampling date, being higher in spring, and as the distance to crops and the biomass of hypogeous arthropods increased. Negative effects of crops on the space use of this bird species might be shaped both by the effect of the crop itself and by its edge effect on hypogeous arthropods. Our results point to an edge effect of crops of 10–50 m on natural vegetation structure, arthropod availability and use of space by the Dupont`s lark, which suggests that the effective area of optimal habitat available for true steppe species could be overestimatedThis study was supported by the Education, Youth and Sport Bureau (Madrid Regional Government, Spain) and the European Social Fund for the Youth Employment Initiative (Spain) [PEJ15/AMB/AI-0059], the European Commission (Spain) [Life-Ricotí project LIFE15-NAT-ES-000802] and the BBVA Foundation (Spain) [BBVA-Dron Ricotí project 026107]. This is a contribution to the Excellence Network Remedinal 3CM (Spain) (S2013/MAE2719), supported by Comunidad de Madri

    Habitat selection by two sympatric rodent species in the Monte desert, Argentina. First data for Eligmodontia moreni and Octomys mimax

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    Habitat selection in deserts is mainly modulated by the availability of resources. The basic hypotheses regarding coexistence of species in arid environments offer two possibilities: 1) coexisting species partition available resources (each species acting as a specialist) and 2) generalists coexist with specialists because the former use habitats which are underused or not selected by the latter. This study presents the first data on macro- and microhabitat selection by Eligmodontia moreni (Cricetidae) and Octomys mimax (Octodontidae), two rodent species which coexist in the most arid part of the Monte desert of Argentina. In order to evaluate both hypotheses, animals were trapped during two seasons (humid and dry) in six macrohabitats of the arid Monte (creosote bush scrub, mesquite woodlands, columnar cactus slopes, barrens, chical and saltbush). A multivariate analysis of variance was used to evaluate differences in PCA components of microhabitat (floristic composition and vegetation structure) among capture and control points. The resulting models suggest E. moreni to be described as a finegrained generalist species, which would be segregated from the specialist O. mimax in shared macrohabitats by resource partitioning, basically related to substrate type and vegetation cover. Our findings accord with theories of community assembly involving generalist and specialist species.Fil: Traba, Juan. Universidad Autónoma de Madrid; EspañaFil: Acebes, Pablo;. Universidad Autónoma de Madrid; EspañaFil: Campos, Valeria Evelin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Giannoni, Stella Maris. Universidad Nacional de San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentin

    Landscape-scale effects of irrigation on a dry cereal farmland bird community

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    Landscape modification and habitat fragmentation are one of the major current threats to biodiversity. The main source of habitat fragmentation is the loss of focal habitat area, but changes in the composition of the surrounding landscape also have a direct effect on biodiversity. These changes may lead to the loss of some species but also may favor species replacement. Farmland birds in Europe are affected by landscape changes due to farmland intensification, such as the spread of irrigation, which may occur at different spatial scales. As irrigation is expected to increase in the coming years, which may affect protected areas, it is necessary to evaluate its potential consequences over focal biodiversity. In this study we assess the relationship between the increase of irrigated land at different spatial scales and changes in a dry cereal farmland bird community, bird abundance and species richness, using generalized linear models. We used a dry cereal farmland affinity index to describe the level of community specificity for dry cereal farmland. The increase in irrigated tree orchards produced an increase in species richness up to 500 m away from the irrigated area, which had a negative effect on the dry cereal farmland bird community, by triggering a replacement of specialist by generalist species. Our results show the importance of landscape-scale effects of irrigation occurring outside protected areas on the farmland bird community inside Natura 2000 sites, as well as how these effects are detected even at long distances from the disturbance source.Departament d’Agricultura, Ramaderia, Pesca i Alimentació and Infraestructures de la Generalitat de Catalunya S.A.U. have funded a relevant part of the field work and data acquisition

    Aplicaciones de SIG y teledetección en ecología: Guión de prácticas de la asignatura

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    Este trabajo surge como resultado del Proyecto de Innovación Docente de la Universidad Autónoma de Madrid – Convocatoria 2013: Adaptación de los recursos informáticos de la asignatura “Aplicaciones de SIG y Teledetección en Ecología” del Máster Oficial en Ecología para la utilización de herramientas de software libre, y elaboración del manual de las prácticas, coordinado por Juan Traba y con la participación de Javier Seoane y Manuel B. Morales; los tres son profesores titulares del Departamento de Ecología de la Universidad Autónoma de Madrid. Ester González de Andrés ha disfrutado de una beca financiada por la la UAM durante la realización de este proyecto. Queremos agradecer expresamente la imprescindible participación de Mª Paula Delgado, Irene Guerrero y Pablo Acebes en la docencia de la asignatura, la preparación y testado de materiales y en la revisión crítica de este documento
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