Conectando mundos distintos: ecología de migración en dos especies de hirundínidos

El comportamiento migratorio constituye una de las adaptaciones más espectaculares de los seres vivos frente a los cambios ambientales del planeta. Este comportamiento ha evolucionado en diversos grupos taxonómicos, desde mariposas a mamíferos, pero sin duda es en las aves donde ha encontrado su mayor desarrollo. Conocer dónde migran las aves siempre ha sido un misterio y no fue hasta finales del siglo XIX cuando comenzó el anillamiento científico. Desde los años ochenta, el desarrollo de nuevas técnicas de marcaje ha permitido obtener datos de gran precisión sobre el comportamiento migratorio. Esta información es necesaria para poder conservar adecuadamente poblaciones de aves migratorias en declive. En esta tesis doctoral, hemos utilizado análisis de isótopos estables y geolocalizadores para estudiar la ecología de migración en la golondrina común (Hirundo rustica) y el avión común (Delichon urbicum). En primer lugar, hemos descrito en detalle el comportamiento migratorio de la golondrina común reproductora en el sur de España. Además hemos identificado que la migración prenupcial es el principal nexo de unión entre lo que ocurre en África durante el invierno y lo que ocurre en Europa durante la temporada de reproducción. A continuación, hemos detectado que las condiciones ambientales experimentadas durante el invierno pueden tener consecuencias sobre la reproducción, lo que resulta sorprendente teniendo en cuenta que ambos eventos se encuentran separados varios meses en el tiempo y miles de kilómetros en distancia. Nuestros resultados revelan que el efecto del hábitat de invernada sobre el posterior éxito reproductor es muy complejo, pues depende de la edad, el sexo y de diferentes variables mediadoras que pueden interactuar entre sí. Aparte del propio valor científico de esta tesis doctoral, nuestros resultados tienen implicaciones en la conservación de especies migratorias y de aves insectívoras. De hecho, muchas especies propias de estos grupos se encuentran amenazadas de extinción o están sufriendo declives poblacionales.Premio Extraordinario de Doctorado U

Loss of largest and oldest individuals of the Montpellier snake correlates with recent warming in the southeastern Iberian Peninsula

The effects of climate change on organisms are now being extensively studied in many different taxa. However, the variation in body size, usually shrinkage in response to increasing temperature, has received little attention regarding to reptiles. During past periods of global warming, many organisms shrank in size, and current evidence and experiments manipulating temperature have shown a biomass decrease in some organisms with increasing temperatures. Here we test whether the body size of the Montpellier snake Malpolon monspessulanus from the southeastern Iberian Peninsula is changing and correlated with the increasing temperature in this region during a 39year period (1976–2014). We measured the snout–vent length (SVL) of vouchers in scientific collections to check for trends in adult body size at the population level in relation with temperature, while controlling for the age of the individuals (estimated by skeletochronology, n¼141). Given the great ontogenetic variation in body size of the study species, we categorized age in 3 classes: “young adults” (under 5 years old), “intermediate adults” (from 5 to 7 years old), and “old adults” (from 8 to 14 years old). By means of linear mixed models, we found a negative relationship between SVL of “old adults” and average annual temperature in the region during the lifetime of each individual. Our results indicate that largest and oldest individuals of the Montpellier Snake, that is, males because of strong sexual size dimorphism in this species, disappeared from the study population, and suggest that it occurred in response to rising environmental temperature.Junta de Andalucía RNM-25

Age-dependent carry-over effects in a long-distance migratory bird

International audienceMigratory birds usually respond to climate change by modifying breeding and/or wintering areas, as well as by reproducing earlier. In addition, changes in winter habitat use or breeding phenology could have important carry-over effects on subsequent breeding success. Here, we studied age-and sex-dependent carry-over effects from wintering to the breeding stage of a small aerial insectivorous long-distance migratory bird, the barn swallows (Hirundo rustica) breeding in Denmark during 1984-2013. First, we used stable isotope analyses combined with ringing recoveries to identify wintering areas. Second, we found that environmental conditions as inferred by Normalized Differential Vegetation Index (NDVI) have deteriorated at the wintering grounds. Third, we used confirmatory path analysis to quantify the indirect effect of winter conditions on subsequent breeding success. Females advanced onset of breeding, laid more eggs and raised more fledglings in the first brood when ecological conditions during the previous winter improved. This response was age dependent, since yearlings did not respond to this environmental cue but the response was increasingly stronger as females aged. Males showed a similar response to winter conditions, although not statistically significant. These results highlight the importance of studying carry-over effects within the context of climate change, especially in relation to age of individuals

An evaluation of isotopic (d2H) methods to provide estimates of avian breeding and natal dispersal

Natal and breeding dispersal represents an important component of animal demography and metapopulation theory. This phenomenon also has implications for conservation and management because understanding movements of individuals potentially allows the identification of key habitats that may be acting as population sources or sinks. Intrinsic markers such as stable isotope abundance in tissues that can be associated with provenance can provide a coarse but pragmatic solution to understanding such movements. Different methodologies have been proposed to quantify natal and breeding dispersal by using stable isotope analyses of keratinous tissues (hair, feathers), each of them with their own advantages and limitations. Here, we compared results provided by four different methods to estimate dispersal (three already published and one novel) in animals using stable isotope measurements. We used a single large dataset of feather δ2H values from golden-winged warblers (Vermivora chrysoptera) representing five different populations breeding in North America to compare model results. We propose one method as the most adequately supported by data, and we used this method to demonstrate how biological factors explaining dispersal status can be identified and geographical origins of immigrants inferred. Our results point to a generalized methodological approach to using stable isotope data to study immigration and dispersal in birds and other animals

Weak Effects of Geolocators on Small Birds: A Meta-analysis Controlled for Phylogeny and Publication Bias

Currently, the deployment of tracking devices is one of the most frequently used approaches to study movement ecology of birds. Recent miniaturization of light-level geolocators enabled studying small bird species whose migratory patterns were widely unknown. However, geolocators may reduce vital rates in tagged birds and may bias obtained movement data. There is a need for a thorough assessment of the potential tag effects on small birds, as previous meta-analyses did not evaluate unpublished data and impact of multiple life-history traits, focused mainly on large species and the number of published studies tagging small birds has increased substantially. We quantitatively reviewed 549 records extracted from 74 published and 48 unpublished studies on over 7,800 tagged and 17,800 control individuals to examine the effects of geolocator tagging on small bird species (body mass <100 g). We calculated the effect of tagging on apparent survival, condition, phenology and breeding performance and identified the most important predictors of the magnitude of effect sizes. Even though the effects were not statistically significant in phylogenetically controlled models, we found a weak negative impact of geolocators on apparent survival. The negative effect on apparent survival was stronger with increasing relative load of the device and with geolocators attached using elastic harnesses. Moreover, tagging effects were stronger in smaller species. In conclusion, we found a weak effect on apparent survival of tagged birds and managed to pinpoint key aspects and drivers of tagging effects. We provide recommendations for establishing matched control group for proper effect size assessment in future studies and outline various aspects of tagging that need further investigation. Finally, our results encourage further use of geolocators on small bird species but the ethical aspects and scientific benefits should always be considered.Grantova Agentura Ceske Republiky 13-06451SInstitut Polaire Francais Paul Emile Victor IPEV-1036Institutional Research Plan RVO: 68081766Leverhulme Trust RPG-2013288Russian Foundation for Basic Research Arctic-18-05-60261Russian Science Foundation 17-14-0114

Environmental conditions during winter predict age- and sex-specific differences in reproductive success of a trans-Saharan migratory bird

Estudios anteriores han relacionado el hábitat de invierno con la fenología de reproducción posterior y la condición física de las aves migratorias, pero pocos han encontrado efectos retardados del hábitat de invierno en el éxito reproductivo posterior. El objetivo de este estudio fue probar si el hábitat de invierno africano está relacionado con el éxito reproductivo posterior de los martines domésticos (Delichon urbicum) que se reproducen en una colonia en España. Medimos los valores de isótopos estables (δ2H, δ13C, δ15N) de plumas en muda en África occidental y utilizamos un análisis de ruta confirmatorio para comprobar si los valores isotópicos de las plumas cultivadas en el invierno estaban relacionados con el éxito reproductivo a través de la mediación de la fenología reproductiva y la condición corporal. Realizamos análisis separados para hombres, mujeres y clases de edad (añales frente a ≥ 2 años). Los machos experimentados que invernan en hábitats de mayor precipitación (como se infiere a partir de valores más bajos de fea2H de la pluma) se encontraban en mejores condiciones corporales y produjeron más descendientes durante la siguiente temporada de reproducción. En contraste, no encontramos ningún efecto del hábitat de invierno en el éxito reproductivo de machos o hembras jóvenes. Estos hallazgos proporcionan evidencia consistente con un vínculo causal complejo entre la calidad del hábitat de invierno y el posterior éxito reproductivo de las aves canoras migratorias de larga distancia.Previous studies have linked winter habitat with subsequent breeding phenology and physical condition of migratory birds, but few have found delayed effects of winter habitat on subsequent reproductive success. The aim of this study was to test if African winter habitat is related to subsequent reproductive success of house martins (Delichon urbicum) breeding at a colony in Spain. We measured stable isotope (δ2H, δ13C, δ15N) values from feathers moulted in West Africa and used confirmatory path analysis to test if isotopic values of winter-grown feathers were related to reproductive success through the mediation of breeding phenology and body condition. We conducted separate analyses for males, females and age classes (yearlings vs ≥ 2 years old). Experienced males wintering in habitats of higher rainfall (as inferred from lower feather δ2H values) were in better body condition and produced more offspring during the subsequent breeding season. In contrast, we did not find any effect of winter habitat on reproductive success of young males or females. These findings provide evidence consistent with a complex causal link between winter habitat quality and subsequent breeding success of long-distance migratory songbirds.• Ministerio de Economía y Competitividad. Proyecto CGL2015-64650-P • Junta de Extremadura. Ayuda IB16121 • Junta de Andalucía. Ayuda P12-RNM-2144 • Universidad de Extremadura. Ayuda A7-26 • Junta de Andalucía. Proyecto P12-RNM-2144, para Cosme López Salmerón • Ministerio de Educación y Ciencia. Becas JC2011-0405 y BES 2004–4886, para Alfonso Marzal Reynolds • Ministerio de Educación y Ciencia. Becas BES-2007-15549 y BES-2010-030295, para Maribel Reviriego Martín • Environment Canada, Ayuda para Keith A. HobsonpeerReviewe

The Mitogenome Relationships and Phylogeography of Barn Swallows (Hirundo rustica)

The barn swallow (Hirundo rustica) poses a number of fascinating scientific questions, including the taxonomic status of postulated subspecies. Here, we obtained and assessed the sequence variation of 411 complete mitogenomes, mainly from the European H. r. rustica, but other subspecies as well. In almost every case, we observed subspecies-specific haplogroups, which we employed together with estimated radiation times to postulate a model for the geographical and temporal worldwide spread of the species. The female barn swallow carrying the Hirundo rustica ancestral mitogenome left Africa (or its vicinity) around 280 thousand years ago (kya), and her descendants expanded first into Eurasia and then, at least 51 kya, into the Americas, from where a relatively recent (&lt;20 kya) back migration to Asia took place. The exception to the haplogroup subspecies specificity is represented by the sedentary Levantine H. r. transitiva that extensively shares haplogroup A with the migratory European H. r. rustica and, to a lesser extent, haplogroup B with the Egyptian H. r. savignii. Our data indicate that rustica and transitiva most likely derive from a sedentary Levantine population source that split at the end of the Younger Dryas (YD) (11.7 kya). Since then, however, transitiva received genetic inputs from and admixed with both the closely related rustica and the adjacent savignii. Demographic analyses confirm this species' strong link with climate fluctuations and human activities making it an excellent indicator for monitoring and assessing the impact of current global changes on wildlife

Pasados y presente. Estudios para el profesor Ricardo García Cárcel

Ricardo García Cárcel (Requena, 1948) estudió Historia en Valencia bajo el magisterio de Joan Reglà, con quien formó parte del primer profesorado de historia moderna en la Universidad Autónoma de Barcelona. En esta universidad, desde hace prácticamente cincuenta años, ha desarrollado una extraordinaria labor docente y de investigación marcada por un sagaz instinto histórico, que le ha convertido en pionero de casi todo lo que ha estudiado: las Germanías, la historia de la Cataluña moderna, la Inquisición, las culturas del Siglo de Oro, la Leyenda Negra, Felipe II, Felipe V, Austrias y Borbones, la guerra de la Independencia, la historia cultural, los mitos de la historia de España... Muy pocos tienen su capacidad para reflexionar, ordenar, analizar, conceptualizar y proponer una visión amplia y llena de matices sobre el pasado y las interpretaciones historiográficas. A su laboriosidad inimitable se añade una dedicación sin límites en el asesoramiento de alumnos e investigadores e impulsando revistas, dosieres, seminarios o publicaciones colectivas. Una mínima correspondencia a su generosidad lo constituye este volumen a manera de ineludible agradecimiento

Unravelling the interface: farm connectivity provided by spotless starling (Sturnus unicolor) movements

Resumen del trabajo presentado a la Joint Virtual Conference of the WDA and EWDA, celebrada del 31 de agosto al 2 de septiembre de 2021.Peer reviewe

Wing morphology covaries with migration distance in a highly aerial insectivorous songbird

According to classical prediction of aerodynamic theory, birds and other powered fliers that migrate over long distances should have longer and more pointed wings than those that migrate less. However, the association between wing morphology and migratory behavior can be masked by contrasting selective pressures related to foraging behavior, habitat selection and predator avoidance, possibly at the cost of lower flight energetic efficiency. We studied the handwing morphology of Eurasian barn swallows Hirundo rustica from four populations representing a migration distance gradient. This species is an aerial insectivore, so it flies extensively while foraging, and may migrate during the day using a ‘fly-and-forage’ migration strategy. Prolonged foraging flights may reinforce the effects of migration distance on flight morphology. We found that two wings’ aerodynamic properties—isometric handwing length and pointedness, both favoring energetically efficient flight, were more pronounced in barn swallows from populations undertaking longer seasonal migrations compared to less migratory populations. Our result contrast with two recent interspecific comparative studies that either reported no relationship or reported a negative relationship between pointedness and the degree of migratory behavior in hirundines. Our results may thus contribute to confirming the universality of the rule that longer migrations are associated with more pointed wings.Junta de Andalucía P12-RNM-2144National Science Centre DEC-2013/09/B/NZ8/03321European Union 106