Person:
Barrientos Yuste, Rafael

First Name

Rafael

Last Name

Barrientos Yuste

URI

https://hdl.handle.net/20.500.14352/81128

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Biológicas

Department

Biodiversidad, Ecología y Evolución

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Now showing 1 - 10 of 15

Can we explain regional abundance and road-kill patterns with variables derived from local-scale road-kill models? Evaluating transferability with the European polecat
(Diversity and Distributions, 2012) Miranda, Juan de Dios; Barrientos Yuste, Rafael
Aim We evaluated the transferability of variables previously found to have a significant effect on European polecat Mustela putorius road-kills at a local scale (i.e. 50 m around location points) when we extrapolate them to a large scale [Universal Transverse Mercator (UTM) 100 km2] in a neighbouring area. Location Andalusia, south Spain. We carried out our study in 821 of the 985 UTM 100 km2 cells included in this region. Methods The units of the different variables were adapted to the new scale. We used data from the Spanish Atlas survey to obtain the abundance of the different species and GIS data for the rest of the variables. We controlled the spatial autocorrelation by incorporating spatial filters obtained with Spatial Eigenvector Mapping into multiple regression analyses. We used AIC criteria and the best subset procedure to investigate the relationship between the selected variables and species abundance, and road-kill occurrence. Results The best subset procedure provided two models that explained 40% of variation in polecat abundance and eleven models that explained around 25% of variation in road-kills. The main explanatory factor for polecat abundance was the abundance of other carnivores, whereas polecat abundance was the main factor for road-kills. In both cases, rabbit abundance was the second most important explanatory variable. Main Conclusions Our findings highlight the possibility of partially explaining the abundance and road-kill patterns at a large scale based on significant variables from local-scale models. Mitigation measures to reduce polecat fatalities should combine actions at different scales. Routes that cross carnivore hotspots, including those of polecats, and areas with important populations of rabbits, should be avoided during road planning. When these routes are unavoidable, local-scale mitigation measures must be implemented.
Eurasian otters modify their trophic niche after the introduction of non-native prey in Mediterranean fresh waters
(Biological Invasions, 2014) Merino-Aguirre, Raquel; Fletcher, David H; Almeida, David; Barrientos Yuste, Rafael
Abstract Biological invasions are a major driver behind disturbances in freshwater community structure. We investigated how the foraging strategy of the Eurasian otter Lutra lutra (L.) has responded to this change in a Mediterranean catchment of the Iberian Peninsula, over a 30-year time span (1980 vs. 2010). We found that, despite continuing to feed on a considerable amount of native fish, this carnivore has adapted its trophic niche to accommodate non-native species. Prior to the massive introductions of these new food items (1980), otters diversified their diet during the limiting season (i.e. summer drought). However, otters had largely incorporated non-native prey into their diet in 2010, with red-swamp crayfish being their main food resource, especially in the summer. This increased crayfish consumption reflects a narrowing of trophic niche during the summer drought in 2010. We discuss how this heavy specialisation may compromise the conservation of otters and their endemic fish prey.
Year-round defecation pattern in wild genets (Genetta genetta L.) in a mountain forest (Toledo, central Spain)
(Polish Journal of Ecology, 2006) Barrientos Yuste, Rafael; Polish Academy of Sciences
Faeces are used by many territorial car-nivores as a communication tool (G or man 1990). A lot of species, from small muste-lids (Hutchings and White 2000) to big predators (Vi l á et al. 1994, Mat yush k i n 2000), leave their scats in places where the probability of interception by other animals is maximal and which are associated with reference points that may visually and/or ol-factorily increase the effectiveness of the signal. The pattern and frequency of marking within species varies with the sex, social and reproductive status of the individual (Mac-dona ld 1980). Common genet (Genetta genetta Linneus 1758) is a medium-sized carnivore distributed in southwestern Europe (L ar iv ière and C a lzad a 2001). It is a territorial species (Pa lomares and D elib es 1994, Zub ero-goit i a et al. 2002, Munuera and L lob e t 2004) that deposits its scats in latrines (R o e der 1980a, Virgós et al. 1996, 2001), which can be used multiply by the same individual or by familiar groups, using such latrines as marking tools (R o e der 1980a). Ano-urogenital marking in males increases during the breeding season and decreases when this ends (R o e der 1978). Scent marks in common genets permit assessment of social status and may allow individual recognition (R o e der 1980b). When present, rocks are the commonest defecation location, but other elevated points such as tree branches, walls or raptor nests can also be used (L ive t and R o e der 1987, Pa lomares 1993, Vi rgós et al. 1996). Def-ecation behaviour of genets in the wild has been studied by Pa lomares (1993) in Do-ñana National Park (Southwestern Spain), where two annual peaks in the number of faeces at latrines were found. The first one, in February and March, could be related to the mating period. The second one, in November and December, is coinciding with the dispersal period of cubs and with a secondary rut season (D el ib es 1974, Ay mer ich 1982). Rocks are not available in Doñana (Pa lo-mares 1993). The aim of this study is to test whether the number of scats as well as the height of their deposition (above the ground) is related to the period of reproductive cycle. The study was carried out in Toledo Mountains (Central Spain; 39º35´N, 4º 41´W).
Meta-analysis of the effectiveness of marked wire in reducing avian collisions with power lines
(Conservation Biology, 2011) Alonso, Juan Carlos; Ponce, Carlos; Palacín, Carlos; Barrientos Yuste, Rafael
Collisions of birds with power transmission and distribution lines have been documented for many species, and cause millions of casualties worldwide. Attempts to reduce mortality from such collisions include placing bird flight diverters (i.e., wire markers in the form of, e.g., spirals, swivels, plates, or spheres) on static and some electrified wires to increase their visibility. Although studies of the effectiveness of such devices have yielded contradictory results, the implementation of flight diverters is increasing rapidly. We reviewed the results of studies in which transmission or distribution wires were marked and conducted a meta-analysis to examine the effectiveness of flight diverters in reducing bird mortality. We included in our meta-analysis all studies in which researchers searched for carcasses of birds killed by a collision with wires. In those studies that also included data on flight frequency, we examined 8 covariates of effectiveness: source of data, study design, alternate design (if marked and unmarked spans were alternated in the same line), periodicity of searches for carcasses, width of the search transect, and number of species, lines, and stretches of wire searched. The presence of flight diverters was associated with a decrease in bird collisions. At unmarked lines, there were 0.21 deaths/1000 birds (n =339,830) that flew among lines or over lines. At marked lines, the mortality rate was 78% lower (n =1,060,746). Only the number of species studied had a significant influence on effect size; this was larger in studies that addressed more species. When comparing mortality at marked and unmarked lines, we recommend use of the same time intervals and habitats and standardizing the periodicity of carcass searches
Railway Ecology
(2017) Borda-de-Agua, Luis; Beja, Pedro; Pereira, Henrique M; Barrientos Yuste, Rafael; Borda-de-Agua, Luis; Barrientos, Rafael; Beja, Pedro; Pereira, Henrique M; Barrientos Yuste, Rafael
This book provides a unique overview of the impacts of railways on biodiversity, integrating the existing knowledge on the ecological effects of railways on wildlife, identifying major knowledge gaps and research directions and presenting the emerging field of railway ecology. The book is divided into two major parts: Part one offers a general review of the major conceptual and theoretical principles of railway ecology. The chapters consider the impacts of railways on wildlife populations and concentrate on four major topics: mortality, barrier effects, species invasions and disturbances (ranging from noise to chemical pollution). Part two focuses on a number of case studies from Europe, Asia and North America written by an international group of experts.
Hatching asynchrony vs. foraging efficiency: the response to food availability in specialist vs. generalist tit species
(Scientific Reports, 2016) Bueno-Enciso, Javier; Sanz Cid, Juan José; Barrientos Yuste, Rafael
Breeding mistiming is increasingly frequent in several ecosystems in the face of current climate change. Species belonging to higher trophic levels must employ mechanisms to reduce it. One of these mechanisms is hatching asynchrony, with the eggs in a clutch hatching over a period of several days. Some authors have suggested it to be adaptive when food is unpredictable. However, these birds can also suffer associated costs. We tested whether a species with higher foraging efficiency avoid hatching asynchrony compared to its sister species. We studied hatching asynchrony and nestling provisioning in relation to food availability in sympatric populations of blue and great tits. For the first time, we show that sister species respond to food availability with different strategies. Blue tit feeding rates readily responded to the abundance of their main prey, and also reduced the impact of nestling size hierarchy on mean nestling weight, consequently increasing fledging rate. Our results suggest that levels of hatching asynchrony seem to be influenced by species-specific life history traits, as generalist foragers rely less on it. They also highlight the importance of multi-species approaches when studying the response of organisms to environmental unpredictability
Wire marking results in a small but significant reduction in avian mortality at power lines: a BACI designed study
(PLoS ONE, 2012) Ponce, Carlos; Palacín, Carlos; Martín De La Calle, Carlos Alfonso; Martín, Beatriz; Alonso, Juan Carlos; Barrientos Yuste, Rafael
Background Collision with electric power lines is a conservation problem for many bird species. Although the implementation of flight diverters is rapidly increasing, few well-designed studies supporting the effectiveness of this costly conservation measure have been published. Methodology/Principal Findings We provide information on the largest worldwide marking experiment to date, including carcass searches at 35 (15 experimental, 20 control) power lines totalling 72.5 km, at both transmission (220 kV) and distribution (15 kV–45 kV) lines. We found carcasses of 45 species, 19 of conservation concern. Numbers of carcasses found were corrected to account for carcass losses due to removal by scavengers or being overlooked by researchers, resulting in an estimated collision rate of 8.2 collisions per km per month. We observed a small (9.6%) but significant decrease in the number of casualties after line marking compared to before line marking in experimental lines. This was not observed in control lines. We found no influence of either marker size (large vs. small spirals, sample of distribution lines only) or power line type (transmission vs. distribution, sample of large spirals only) on the collision rate when we analyzed all species together. However, great bustard mortality was slightly lower when lines were marked with large spirals and in transmission lines after marking. Conclusions Our results confirm the overall effectiveness of wire marking as a way to reduce, but not eliminate, bird collisions with power lines. If raw field data are not corrected by carcass losses due to scavengers and missed observations, findings may be biased. The high cost of this conservation measure suggests a need for more studies to improve its application, including wire marking with non-visual devices. Our findings suggest that different species may respond differently to marking, implying that species-specific patterns should be explored, at least for species of conservation concern.
Refugia, colonization and diversification of an arid-adapted bird: coincident patterns between genetic data and ecological niche modelling
(Molecular Ecology, 2014) Kvist, Laura; Barbosa, Andrés; Valera, Francisco; Khoury, Fhares; Varela, Sara; Moreno, Eulalia; Barrientos Yuste, Rafael
Phylogeographical studies are common in boreal and temperate species from the Palaearctic, but scarce in arid-adapted species. We used nuclear and mitochondrial markers to investigate phylogeography and to estimate chronology of colonization events of the trumpeter finch Bucanetes githagineus, an arid-adapted bird. We used 271 samples from 16 populations, most of which were fresh samples but including some museum specimens. Microsatellite data showed no clear grouping according to the sampling locations. Microsatellite and mitochondrial data showed the clearest differentiation between Maghreb and Canary Islands and between Maghreb and Western Sahara. Mitochondrial data suggest differentiation between different Maghreb populations and among Maghreb and Near East populations, between Iberian Peninsula and Canary Islands, as well as between Western Sahara and Maghreb. Our coalescence analyses indicate that the trumpeter finch colonized North Africa during the humid Marine Isotope Stage 5 (MIS5) period of the Sahara region 125 000 years ago. We constructed an ecological niche model (ENM) to estimate the geographical distribution of climatically suitable habitats for the trumpeter finch. We tested whether changes in the species range in relation to glacial–interglacial cycles could be responsible for observed patterns of genetic diversity and structure. Modelling results matched with those from genetic data as the species' potential range increases in interglacial scenarios (in the present climatic scenario and during MIS5) and decreases in glacial climates (during the last glacial maximum, LGM, 21 000 years ago). Our results suggest that the trumpeter finch responded to Pleistocene climatic changes by expanding and contracting its range.
Nesting habitat selection of Mediterranean raptors in managed pinewoods: searching for common patterns to derive conservation recommendations
(Bird Conservation International, 2014) Arroyo, Bernardo; Barrientos Yuste, Rafael
Investigating habitat selection is a key step in improving the population conservation of forest species in areas managed for different purposes, from timber harvesting to hunting or recreation. Because economic resources allocated to conservation are limited, studies that assess cost-effective strategies are necessary, especially when concerning non-threatened species. We studied nest-site habitat selection of two raptor communities (totalling 245 nests from the five most common species: Short-Toed Eagle Circaetus gallicus, Goshawk Accipiter gentilis, Sparrowhawk A. nisus, Common Buzzard Buteo buteo and Booted Eagle Aquila pennata) in two pinewoods in central Spain separated by 200 km. Using a Generalised Linear Mixed Model for each species and with locality as a random factor, we obtained five models of habitat selection. We highlighted the common nesting patterns in order to facilitate an integrated management of forestry in relation to raptor nesting habitat selection. The most important variable for all species, with the exception of the Sparrowhawk was the nest-tree diameter at breast height, with raptors preferentially selecting nesting trees of large width. Tall trees and a high amount of tree cover around the nesting tree were also important habitat features for several species. Our results suggest that pinewoods should retain unharvested patches with moderate tree coverage (30–70%) containing not only several large trees (diameter at breast height > 40 cm) but also small ones. At the landscape level, open forests and heterogeneous habitats are preferred. These forest patches should be dispersed throughout the landscape.
Reduction of potential food interference in two sympatric carnivores by sequential use of shared resources
(Acta Oecologica, 2006) Virgós, Emilio; Barrientos Yuste, Rafael
The common genet (Genetta genetta) and the stone marten (Martes foina) are two species that overlap extensively in their distribution ranges in southwest Europe. Available diet data from these species allow us to predict some interference competition for food resources in sympatric populations. We checked the food interference hypothesis in a sympatric population. The diet of both predators was analyzed through scat collection. Seasonal differences in biomass consumption were compared between both species in those items considered as key resources according to biomass consumption. Strawberry tree fruits can be considered as key resource exclusively for genets whereas fungi, blackberries and rabbits are keys for stone martens only. For other key resources consumed by both species (wood mouse and figs) we suggest that a possible mechanism to reduce diet overlap could be the sequential use of these resources: no intensive exploitation by both species of the same key resource during the same season was detected. Figs and wood mouse were used alternatively. Although strawberry tree fruits and blackberry are exclusive key resources of one of the species, their consumptions showed the same pattern. Diet niche overlap in our study is low compared with other carnivore communities suggesting that exclusive use of some key resources and sequential use of shared ones is an optimal scenario to reduce overall competition for food resources.