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Woodlands subjected to commercial exploitation can play an important role in the conservation of forest-dwelling birds, whether these species breed, forage, or spend all or part of their annual cycle in this habitat. Since 2016, the Administration of Gipuzkoa Province, Spain, has implemented a new protocol designed to preserve the nesting habitat of the Red Kite (Milvus milvus) population breeding within the region. This species is locally classified as endangered and therefore has conservation priority. The aim of our study was to evaluate the efficacy, demographic impact, and cost of this protocol. Over a period of 7 yr (2016–2022), implementation of the protocol preserved 23 nests (i.e., 15.2% of the total 151 nests). From these protected nests, 37 young fledged, which was 16% of all the young fledged within the region in this period. Relative to the financial cost of protecting nature in Gipuzkoa, implementation of this protocol was inexpensive, totalling <0.1% of the administration's budget for managing natural habitats within the province. Los bosques sometidos a explotación comercial pueden desempeñar un papel importante en la conservación de aves que habitan en ellos y se reproducen, forrajean o pasan todo o parte de su ciclo anual allí. Desde 2016, la Administración de la Provincia de Gipuzkoa, España, ha diseñado e implementado un nuevo protocolo con el fin de preservar el hábitat de nidificación de la población de Milvus milvus que se reproduce en la región, ya que esta especie está clasificada como localmente en peligro de extinción y, por lo tanto, tiene prioridad de conservación. El objetivo de nuestro estudio fue evaluar la eficacia, el impacto demográfico y el costo de este protocolo. Durante un período de siete años (2016–2022), la implementación del protocolo preservó 23 nidos (es decir, el 15.2% del total de 151 nidos). De estos nidos protegidos, 37 crías emplumaron, lo que representó el 16% de todas las crías emplumadas en la región en este período. En relación con el costo financiero de proteger la naturaleza en Gipuzkoa, la implementación de este protocolo fue económica, totalizando <0.1% del presupuesto del departamento para la gestión de hábitats naturales en la provincia. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

During migration, landbirds normally need to stop-over in order to rest and/or acquire fuel stores that power their flight. Refuelling strategies become particularly evolutionarily relevant when birds must cross broad geographic barriers, where the chance to land and get food is nil, such as when crossing oceans. Our objective was to learn more about the use of the small islands located close to the mainland coast as stopover areas by small migratory birds that cross the Bay of Biscay. Using data collected in a constant-effort mist-netting programme conducted on Izaro Island (northern Spain) during autumn migration (years 2018 to 2021), we aimed to determine (1) which species land on the island and for how long they stay there, and (2) their fuel load and fuel deposition rate. Structurally, the assemblage was dominated by Willow Warblers Phylloscopus trochilus, which on average accounted for 84% of the abundance. Clustering analyses reveal that the assemblage was rather homogeneous across the four study years. Most birds probably stayed on the island for less than 24 hours, with fewer than 5% being recaptured one or more days after their first capture. The first-capture-event body mass of Willow Warblers captured only once (8.0g, 95%CI 7.8-8.4g) did not differ from the initial body mass of those captured two or more times within a season (8.0g, 95% CI 7.0-9.0g), and those stopping over on Izaro had a negative mean fuel deposition rate of –0.2g/day (SE = 0.1g/d). Overall, Izaro was used as an emergency stopover site during the course of this study, where exhausted birds landed after sea-crossings. From a conservation standpoint, and as compared to other stopover sites used as 'emergency' stopover sites, results suggest that Izaro is of little value for replenishing the fuel stores of these small birds during autumn migration.—Betanzos-Lejarraga, L., Guzmán, I., Escandell, R., Unamuno, E. & Arizaga, J. (2023). Stopover ecology of passerine birds on an islet in the Bay of Biscay in autumn reveals a pattern similar to their use of small Mediterranean islands in spring. Ardeola, 70: 241-255. Durante la migración, las aves terrestres normalmente necesitan detenerse para descansar o adquirir las reservas que después consumirán durante el vuelo. Las estrategias para ganar estas reservas se vuelven particularmente relevantes desde el punto de vista evolutivo cuando las aves han de cruzar grandes barreras geográficas en las que la posibilidad de aterrizar y alimentarse es nula, como ocurre al atravesar océanos. El objetivo de este artículo es profundizar en el uso de las pequeñas islas situadas cerca de la costa por las pequeñas aves migratorias que cruzan el golfo de Vizcaya. Utilizando los datos que fueron recolectados mediante un programa de anillamiento científico desarrollado en la isla de Izaro (norte de España) durante el periodo de paso posnupcial (años 2018 a 2021), se pretendió identificar (1) cuáles son las especies que usan la isla y cuánto tiempo permanecen allí, y (2) cuál es su cantidad y tasa de deposición de reservas. Estructuralmente, el ensamblado estuvo dominado por el mosquitero musical Phylloscopus trochilus, que en promedio representó el 84% de la abundancia. Los análisis de clusters revelaron un ensamblado muy homogéneo a lo largo de todo el periodo de estudio. En general el periodo de estancia en la isla fue de un día para la mayoría de los ejemplares capturados para anillamiento, y de ellos menos del 5% fueron recapturados uno o más días después de su primera captura. La masa corporal de la primera captura no varió entre mosquiteros musicales capturados una sola vez en la isla (8,0 g, IC 95 % 7,8-8,4 g) y capturados dos o más veces en la temporada (8,0 g, IC 95 % 7,0-9,0 g). La tasa de ganancia de reservas de los recapturados fue negativa (–0,2 g/d; SE = 0,1 g/d). En general, nuestros resultados sugieren que Izaro es usada como punto de parada migratoria de emergencia por las aves que, tras cruzar el Cantábrico, llegan exhaustas a la costa del norte de España. Desde el punto de vista de la conservación, y en comparación con otros sitios de parada migratoria utilizados, Izaro parece tener poco valor como punto de ganancia de reservas durante el periodo de paso posnupcial. —Betanzos-Lejarraga, L., Guzmán, I., Escandell, R., Unamuno, E. y Arizaga, J. (2023). La ecología de parada de descanso migratorio de las aves paseriformes en un islote del golfo de Vizcaya en otoño revela un patrón similar al uso de las pequeñas islas mediterráneas en primavera. Ardeola, 70: 241-255. [ABSTRACT FROM AUTHOR]

Variability in morphology and body size between populations of the same species is common and can be influenced by environmental conditions or differential migratory strategies. We focused on analysing body size differences between Yellow-legged gulls Larus michahellis from Mediterranean and Cantabrian-Atlantic Iberian colonies as previous studies have suggested that Cantabrian-Atlantic gulls are smaller than Mediterranean gulls. However, those analyses were based on small sample sizes or did not account for sexual dimorphism. Here we analyse an extensive biometric data set (> 1,500 adult individuals), separating males and females, from nine different sites in each region. Our results reveal a 7% (median) difference both between regions and sexes, for most morphometric variables, with Mediterranean gulls having longer legs (tarsi) and heads (cranium-bill) and thicker bills (bill-depth). This inter-regional difference was even larger for body mass, Mediterranean gulls being 11% (males) and 20% (females) heavier than Cantabrian-Atlantic gulls. In particular, we found that individuals from the Mediterranean populations were allometrically longer-winged than their northern counterparts. We suggest, after discarding other factors, that this wing allometry may be related to the sedentariness of the Cantabrian-Atlantic gulls, compared with the partially migratory strategy of Mediterranean gulls. We also suggest that the larger body size of Mediterranean gulls may help them compete better with resident gulls for food acquisition, once they coincide in the Cantabrian-Atlantic region. Finally, females from both populations were also found to be proportionately longer-winged than males. We hypothesise that this difference could allow smaller females to travel longer distances locally in search of food or to make use of different habitat types, avoiding foraging competition with the larger males.—Marcos Pacheco, M.L., Tavecchia, G., Igual, J.M., Alonso-Álvarez, C., Arizaga, J., Galarza, A., Oro, D. & Martínez-Abraín, A. (2023). Yellow-legged Gulls from the Mediterranean are not only larger but also allometrically longer-winged than those from the Cantabrian-Atlantic. Ardeola, 70: 225-240. La variabilidad en la morfología y el tamaño del cuerpo es común entre poblaciones de la misma especie y puede verse influenciada por las condiciones ambientales o por estrategias migratorias diferenciales. En este trabajo nos centramos en analizar las diferencias de tamaño corporal entre las gaviotas patiamarillas Larus michahellis del Mediterráneo y de las colonias ibéricas cántabro-atlánticas, ya que estudios previos sugirieron un tamaño más pequeño de las gaviotas del Cantábrico/Atlántico en comparación con las gaviotas mediterráneas. Sin embargo, esos análisis se realizaron empleando tamaños de muestra pequeños o no tuvieron en cuenta el gran dimorfismo sexual de la especie. Aquí, analizamos un extenso conjunto de datos biométricos (> 1,500 individuos adultos), separando machos y hembras, de nueve sitios diferentes en cada una de las dos regiones. Nuestros resultados revelaron una diferencia del 7% (mediana) tanto entre regiones como entre sexos, para la mayoría de las variables morfométricas, teniendo las gaviotas mediterráneas patas (tarsos) y cabezas (cráneo-pico) más largos y picos (altura de pico) más gruesos. Esta diferencia entre regiones fue aún mayor en el peso, siendo las gaviotas mediterráneas un 11% (machos) y un 20% (hembras) más pesadas que las gaviotas cántabro-atlánticas. Es importante destacar que los individuos de las poblaciones mediterráneas tuvieron alas alométricamente más largas que sus contrapartes del norte. Sugerimos que esta alometría alar puede estar relacionada con el sedentarismo de las gaviotas cantábrico-atlánticas, frente a la estrategia parcialmente migratoria de las gaviotas mediterráneas, tras descartar otros factores. También sugerimos que el mayor tamaño corporal de las gaviotas mediterráneas podría ayudarles a competir mejor con las gaviotas residentes por la adquisición de alimento, una vez coinciden en la región cántabro-atlántica. Finalmente, también se encontró que las hembras de ambas poblaciones tuvieron alas proporcionalmente más largas que los machos. Proponemos que esa diferencia podría permitir que las hembras (más pequeñas) viajen distancias más largas a nivel local en busca de alimento o hagan uso de diferentes tipos de hábitat, evitando la competencia de forrajeo con los machos más grandes.—Marcos Pacheco, M.L., Tavecchia, G., Igual, J.M., Alonso-Álvarez, C., Arizaga, J., Galarza, A., Oro, D. y Martínez-Abraín, A. (2023). Las gaviotas patiamarillas del Mediterráneo no sólo son más grandes que las cántabro-atlánticas sino que además tienen alas alométricamente más largas. Ardeola, 70: 225-240. [ABSTRACT FROM AUTHOR]

Urbanization constitutes one of the most intensive and fast spreading factors explaining biodiversity loss worldwide. The extension of urban areas and landscape configurations affects the ability of raptors to exploit urban patches. The Tawny Owl Strix aluco is a forest-dwelling nocturnal species with a wide distribution range that is well-adapted to urban environments. However, it remains unknown which habitat factors explain its presence in urban-associated landscapes. Our main objective is to determine the effect of urban landscapes on the probability of occurrence of Tawny Owls along an urban-rural gradient. It is expected that Tawny Owls will be able to use urban patches that have (1) at least 30% tree cover thanks to gardens/parks for hunting but (2) they will not use those with high noise levels (i.e., highways). Our research was carried out in the municipality of Donostia-San Sebastian in the Basque Country, Northern Spain. Data were obtained from a survey conducted in 2017. The municipality was divided into 329 square cells, of which 251 were surveyed. Tawny Owls were detected in 141 cells, and we found that nocturnal noise level and scrub cover contributed most to explaining the probability of Tawny Owl occurrence; with nocturnal noise having a significant negative effect on occurrence probability, and scrub cover a positive effect, probably because the species uses open or semi-open areas to hunt (but woodland to breed). Overall, it can be concluded that the very noisy and/or urbanized parts of the city comprised a non-optimal habitat for the species.—Pagaldai, N., Rodríguez-Pérez, J., Arnaiz, A. & Arizaga, J. (2023). Factors shaping occurrence probability of a generalist raptor species across an urban-rural gradient. Ardeola, 70: 75-88. La urbanización es una de las causas más intensivas y rápidas que explican la pérdida de biodiversidad a nivel mundial. La extensión de las áreas urbanas y la configuración del paisaje afectan la habilidad de las rapaces para explotar parches urbanos. El cárabo euroasiático Strix aluco es una especie forestal nocturna con una amplia distribución y bien adaptada a los ambientes urbanos. Sin embargo, siguen siendo desconocidos qué factores relacionados con el hábitat explican su presencia en ambientes urbanizados. Nuestro objetivo general es el de determinar el efecto que tienen los paisajes urbanos en la probabilidad de presencia del cárabo euroasiático a lo largo de un gradiente urbano-rural. Se espera que el cárabo sea capaz de usar los parches urbanos que tengan (1) un mínimo número de jardines/parques con árboles para cazar; y (2) un limitado nivel de ruido durante la noche (ej. autopistas). Nuestro estudio se llevó a cabo en Donostia-San Sebastián, en el País Vasco, norte de España. Los datos se obtuvieron mediante un censo realizado en 2017. El municipio se dividió en 329 cuadrículas y 251 de ellas fueron censadas. Se detectaron cárabos en 141 cuadrículas, y obtuvimos que el ruido nocturno y la cubierta de matorral fueron las variables que más contribuyeron a explicar la probabilidad de presencia; el ruido nocturno tuvo un significativo efecto negativo en la probabilidad de presencia, mientras que la cubierta de matorral tuvo un efecto positivo, probablemente porque la especie utiliza áreas abiertas o semiabiertas para cazar (pero bosques para criar). En general, se puede concluir que las zonas más ruidosas y urbanizadas de la ciudad componen un hábitat no óptimo para la especie.—Pagaldai, N., Rodríguez-Pérez, J., Arnaiz, A. y Arizaga, J. (2023). Factores que afectan a la probabilidad de presencia de una rapaz generalista a lo largo de un gradiente urbano-rural. Ardeola, 70: 75-88. [ABSTRACT FROM AUTHOR]

The main goal of this study was to describe in detail the structure and phenology of flocks of the Common Linnet (Linaria cannabina) passing through eastern Spain. Data were compiled during the spring and autumn migrations of 2019 to 2021 (excluding spring 2020), by counting and by capture for ringing. We counted 6151 flocks, comprising 17 732 birds, of which 7638 individuals were captured. The size of flocks ranged from 1 to 30 Linnets (mean ± 95% CI, 2.8 ± 0.1), with a higher proportion of solitary migrants in spring (46.8%) than in autumn (33.8%). Passage in spring peaked during the third hour after dawn, whilst in autumn this peak was just after dawn. There were more females than males (56%), probably as an indicator of latitudinal differential migration. Juveniles were significantly more abundant (c. 80%) than adults. The phenological pattern of the passage was more variable in spring than in autumn, and such variation could be useful to explore potential impacts of climate change on the migration ecology of the species. [ABSTRACT FROM AUTHOR]

We aimed to describe the morphologic and isotopic differences of European Goldfinches Carduelis carduelis according to their migratory behaviour or geographic origin. We compared morphologic and isotopic variables between birds caught in two different obligatory migratory pathways (eastern and western border of the Pyrenees) and throughout the post-breeding period (from late summer to winter). The isotopic and morphological traits varied across seasons (from autumn to winter), indicating that birds captured later in the season had traits typical of longer-distance migrants that come from regions situated further north. Moreover, our results suggest that Goldfinches caught in the eastern and western borders of the Pyrenees slightly differ in body size and in one of the two colour patch-associated traits, but not in their flight apparatus or isotopic values, these last being more strongly related to their areas of origin. Such observed regional differences, therefore, may be more strongly related to other selection pressures. [ABSTRACT FROM AUTHOR]

In colonial seabirds, the nest substrate that is available and, in particular, the vegetation cover around the nest, are important environmental factors that drive an individual's nesting selection process and, ultimately, reproductive performance. Using data collected during three consecutive years in a Yellow-legged Gull Larus michahellis colony from the Bay of Biscay, Spain, we tested whether clutch size, egg volume, and hatching success covaried with the proportion of vegetation cover around nests. We found no effect of vegetation cover on breeding performance. Laying date showed a positive effect on egg volume and a negative effect on hatching success and the number of hatched eggs. Egg volume tended to be smaller in 2020 compared to 2018 and 2019, and hatching success decreased through the sampling period, with the lowest hatching success occurring in 2020. Our findings agree with a previous study in which vegetation had no or unclear effects on breeding performance in Yellow-legged Gulls; however, they contradict other seabird studies that found a positive correlation between the two variables. The role of vegetation on breeding performance could vary not only between gull species, but also geographically, with ecological drivers such as intra- and interspecific interactions and climate playing key roles in observed differences. Finally, the use of egg volume and hatching success as proxies for breeding output could be used for the long-term monitoring of the relationship between breeding performance and factors such as landfill management, fishing, or climate change in the Yellow-legged Gull and other gull species. [ABSTRACT FROM AUTHOR]

The Bay of Biscay is an important non-breeding area for some Palaearctic gull species and populations. The aim of this work is to describe the spatial and temporal distributions of non-breeding gulls in the Bay of Biscay, and to identify their major areas of origin. With that goal, we analysed 6773 live sightings of colour-ringed gulls within the southeastern part of the Bay of Biscay during the 20 years 2000–19, relating to 2552 individuals of 10 species. Their distribution along the coast was not homogeneous, with numbers peaking in most cases from November to February, though some species were observed to peak around midsummer. Their origins comprised a wide geographical area encompassing western and eastern Europe; overall, the species can be divided into four groups by origin: northwestern France with Britain and Ireland, central western Europe (with a centroid in the Benelux region), eastern Europe, and the western Mediterranean. [ABSTRACT FROM AUTHOR]

Important biological parameters, such as movement and survival, can differ substantially between sexes, driving the demographic patterns of a population. Sex-dependent spatial segregation at the foraging grounds can evolve as a mechanism to reduce competition for resources between sexes, among other causes. Investigating such segregation, especially in scenarios of decreasing food availability, can contribute to understanding how birds adapt to a fast-changing world. The aim of the present study was to determine whether year-round movements and survival varied between sexes within a resident Yellow-legged gull Larus michahellis population. To this end we used live encounter data on colour-ringed Yellow-legged Gulls in northern Spain in the period 2009–2017. We used Generalized Linear Models to analyse distance to the colony of origin and multi-state models to estimate both survival and year-round movements, which did not provide evidence supporting an effect of sex on movement and survival. In contrast, distances travelled from the natal colony varied between seasons and all gulls were more likely to move greater than 100 km from natal sites. Juveniles showed lower survival rates (0.55) than older birds (0.90). Future research with GPS data might help to reveal, if existing, the occurrence of local spatial segregation between sexes that otherwise remains undetected. [ABSTRACT FROM AUTHOR]

Copyright of Ardeola is the property of Sociedad Espanola de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Determining the age of specimens is of great help in wildlife management, especially for rare or threatened species in which each individual has a high value. In birds, differences in moulting pattern between juveniles and adults may in some cases allow determination of a bird's age from the examination of its plumage. In the present study, we analyse the moult of 19 breeding individuals of White-backed Woodpecker Dendrocopos leucotos lilfordi captured for GPS tagging in the Pyrenees, in order to describe, for the first time, the moulting pattern of this endangered woodpecker. Two well-differentiated groups of adult birds were identified: those that underwent a partial moult, and were classified as second-calendar-year birds, and those that performed a complete one and were classified as older. The first group had renewed most lesser and median coverts, all primaries and the innermost greater coverts, thus showing clear moult limits between the primaries and secondaries and within the greater coverts. Some individuals also replaced up to two more greater coverts (GC5–6). Individuals classified as older birds showed all feathers to be of a single generation, indicating that they had undergone a complete moult. A few individuals in this category retained a few unmoulted secondaries and primary coverts, however. A recapture of a bird with a complete moult, which had been captured a year before showing a partial moult, would confirm these moult sequences to be age dependent. This moulting pattern is very similar to that described for other spotted woodpeckers, and allows researchers to determine the ages of breeding individuals during the nesting season. [ABSTRACT FROM AUTHOR]

Copyright of Ardeola is the property of Sociedad Espanola de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Ornithologica is the property of Polska Akademia Nauk, Muzeum i Instytut Zoologii and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During migration, birds often need to gain large fuel loads, especially if they must cross large geographic barriers with poor or absent fuelling opportunities. The Willow Warbler is a songbird associated with woodland that also opportunistically exploits other habitat types, such as reed beds, allowing it to fuel quickly. Reed beds along the coast of the Bay of Biscay constitute potentially targeted fuelling sites for birds moving from northern Europe to Africa in autumn. Using data obtained from a ringing station, we tested to what extent these coastal sites are opportunistically used by Willow Warblers. The study was carried out in a reed bed area at Txingudi marshlands, one of the main wetlands at the Bay of Biscay in northern Iberia. We found that when Willow Warblers were more abundant, that birds deposited fuel more quickly, and that annual mean fuel load was correlated with the number of captures, suggesting opportunistic stopover exploitation. [ABSTRACT FROM AUTHOR]

The migratory behaviour of European Song Thrush (Turdus philomelos) populations ranges from resident in the south and west to partly or totally migratory in northern, central and eastern Europe. This varied migratory behaviour could be reflected in morphological adaptations, with migrants having a proportionally longer wing, lower tail:wing ratio, and, if foraging more on fruits, deeper and wider bills. We used data from Song Thrushes captured during the breeding season and in winter in northern Iberia to test for morphological variations between these two periods. In three consecutive years (2014-16), Song Thrushes were captured with mist nests in a region of southern Navarra (Spain) during the breeding season (from May to July) or in the winter period (October to February), during a period of four hours starting at dawn per sampling day. We consider the winter population to be composed of a high proportion of visitors. Breeding Song Thrushes showed proportionally longer tails for given wing lengths, even though wing length did not vary between the two periods. Moreover, winter visitors showed narrower and less deep bills than breeding Song Thrushes. Potential explanations for these results are discussed. [ABSTRACT FROM AUTHOR]

Dredging and/or dumping actions at coastal environments are a common phenomenon worldwide. The re-working of dumped sediments from their disposal sites to places of great ecological value can have a very strong impact on the ecosystems through deep changes over the communities and the trophic web. Using a relevant dredging-dumping episode carried out in 2003 at Urdaibai, one the chief estuary areas in northern Iberia, we tested the consequence of this action on the subsequent use of the zone by shorebirds. The surface sediment characteristics before and after the dredging and dumping actions were also compared. The dredging at Urdaibai showed a negative effect on bird abundance in three out of the eight species tested overall (dunlin, grey plover, common ringed plover). Highest-ranked models supported a decrease in their population sizes two years after the event. In this scenario, local authorities should be appealed to take dredging and dumping effects into account in order to improve the estuary management. [ABSTRACT FROM AUTHOR]

Crimean-Congo hemorrhagic fever virus (CCHFV) was detected in Spain in 2010. The presence of CCHFV in Hyalomma marginatum ticks from migratory birds passing through Morocco during the spring migration strengthened the hypothesis of the arrival of infected ticks transported by birds to the Iberian Peninsula. Furthermore, Hyalomma species are vectors of bacterial infections such as spotted fever rickettsioses. CCHFV and Rickettsia were screened in Hyalomma ticks from Spain attached to patients (n = 12) and birds (n = 149). In addition, Rickettsia was investigated in 52 Hyalomma ticks from Morocco (previously reported as CCHFV-infected). No sample collected in Spain showed an infection with CCHFV. Two ticks removed from patients (16.7%), as well as 47 (31.5%) and 4 (7.7%) from birds, collected in Spain and Morocco respectively, were infected with Rickettsia aeschlimannii . Rickettsia sibirica subsp. mongolitimonae was also found in 2 ticks from birds collected in Spain (1.3%). The risk of CCHFV-infected ticks attached to migratory birds to reach the North of Spain is low. This study corroborates the presence of R. aeschlimannii in Spain and Morocco, and supports that H. marginatum can be a potential vector of R. sibirica subsp. mongolitimonae in the Iberian Peninsula. [ABSTRACT FROM AUTHOR]

Copyright of Ardeola is the property of Sociedad Espanola de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ardeola is the property of Sociedad Espanola de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ardeola is the property of Sociedad Espanola de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Body condition of nestlings can influence their future survival. Here, we used data obtained from a colourringing program of Yellow-legged Gull Larus michahellis in two colonies from northern Iberia to quantify the relative importance of pre-fledging body size and mass on post-fledging juvenile survival. Chicks were ringed with colour-rings at their colony in June/July when they were almost ready to fledge, and, thereafter, sighting data of these birds were collected over a period of one year and analysed with Cormack-Jolly-Seber capture-recapture models. The Yellowlegged Gull in the region is resident, so sighting data were mostly collected within an area close to natal colonies, where the field effort was intensive. Monthly survival from August onwards was higher than from ringing date to August (0.59± 0.06 SE), reaching model averaged values of 0.91 ± 0.03 and 0.98 ± 0.03 for the two colonies analysed. Moreover, condition of chicks (measured as residual body mass and body size) before fledging had a positive effect on survival from ringing date to August, but not from August onwards, when survival was strongly affected by the colony of origin. [ABSTRACT FROM AUTHOR]

The authors discuss the results of their study on the role of age, colony of origin and year on the survival of yellow-legged gulls Larus michahellis in the bay of Biscay. The percentage of gulls seen alive in Gueraria range from 36% to 52%. Mean survival rate for age and classes is lowest among gulls from Izaro. Colony size was not linked with survival.

The article explores the phenological parameters of bluethroats Luscinia svecica azuricollis population breeding in high altitude in central Spain. The small percentage of moulting first-year birds compared to all captured in August and September suggests that birds experience post-juvenile moult just after fledging. First-year birds appeared within the population in June. Population of adults in breeding area fell from August to the rest of the year.

In sites where habitat loss has been intense, or where human disturbance is high, the restoration or creation of undisturbed habitats for species of concern is fundamental for wildlife conservation. In 2009, a 11.5 ha area in the upper marsh at Urdaibai (North of Spain) was excavated, and a new, stable lagoon of brackish water built in its place. In contrast to the rest of Urdaibai, the lagoon was not tidal, and it had lower reported rates of human disturbance than the rest of Urdaibai. Our aim was to quantify the benefits of this lagoon on Eurasian Spoonbill ( Platalea leucorodia ) populations. The lagoon hosted 42% of the spoonbills deciding to stop over at Urdaibai, although only representing ca. 1% of the total marsh and 6% of the area effectively used by spoonbills. Spoonbills at the lagoon invested less time in foraging, but had higher foraging success rates than birds stopping over in other areas of Urdaibai. Most spoonbills only stopped over at Urdaibai for <24 h whilst migrating, but the longest stopover periods were detected at the lagoon. It appears the lagoon has improved the quality of Urdaibai as a stopover site for the Eurasian Spoonbill in the Bay of Biscay region. However, more work is needed to verify the suggested energetic benefits of the new lagoon in order to assess the full degree to which the newly constructed lagoon benefitted local spoonbills, and to ascertain if this kind of management could benefit the species more widely. [ABSTRACT FROM AUTHOR]

The article discusses research which investigated population dynamics of the little egrets Egretta garzetta colony on Izaro Island in Northern Spain. Topics explored include the nesting and breeding behavior of little egrets on the study location, the modeling of colony growth rate and estimates of survival, and the recorded bird population during the winter season.

The article discusses research which investigated the impact of meteorological conditions and bird's age on the landing decisions of migrating sedge warblers, Acrocephalus schoenobaenus, in northern Iberia. Topics explored include the breeding and migratory behavior of sedge warblers, the sampling and analysis of capture-mark-recapture (CMR) data gathered, and the recording of other factors which tend to influence bird migration.

The article that first evidence of nocturnal flight overland was provided by satellite telemetry Osprey. Topics include an osprey reintroduction program was initiated at Urdaibai Biosphere Reserve for interconnecting small breeding population; use of raptors for avoiding associated risks such as starvation, dehydration, and disorientation; and collection of ospreys under license of the Scottish Natural Heritage.

The article presents a study which examined the characteristics of Riparia riparia colonies in artificial river walls. 16 variables from artificial walls with pipes in channelled rivers between walls holding or not holding a colony of the species were compared. The presence of colonies was found to be negatively associated with the distance of the breeding wall from the water and positively with flooding risk.

The article focuses on a study on the creation of the Orueta Lagoon influenced the waterbird diversity in Urdaibai, Spain. According to the author, artificial wetlands can mitigate the loss and degradation of natural wetlands. The study concludes that the lagoon was able to provide new and attractive habitat for several waterbird species as it contributed to 26.8% of total abundance in population.

The article discusses a study which assessed the apparent survival rate and its variation between age classes and years for a breeding population of bluethroat Luscinia svecica azuricollis in Spain. Topics discussed include the importance of survival estimation to understanding population dynamics, the use of Cormack-Jolly-Seber models on capture-recapture data obtained during the 1998-2005 breeding season and the higher apparent survival exhibited by bluethroats.

The article details a study of the degree of connectivity in the Eurasian Reed Warbler, Acrocephalus scirpaceus, between breeding grounds (BG) in central and northern Europe and stopover areas in Iberia during the autumn migration. Among the methods used include biometric analyses for wing pointedness, and generalized linear model for checking the morphological variations between migratory regions. Researchers found a relatively low connectivity between BG in Europe and passage areas in Iberia.

The article reports on the spatial behaviour and habitat use of first-year Bluethroats Luscinia svecica during migration. It examines the impact of tide on home range size of Bluethroats at coastal marshes by using data on radio-tagged birds in Northern Iberia. It discusses the role played by coastal marshes as stopover and fuelling sites for birds during migration period. It mentions the stopover behavior of land birds, which depend on these sites.

The article discusses the results of a study which examines the effect of microclimate and human disturbance on microhabitat of Bramblings Fringilla montifringilla in a roosting site during the winter season. The authors noted the factors influencing the preference of Brambling for roosts and their site selection and bird density including vegetation, microclimate, topography, and sources of disturbance. The study indicated that protection from winds and radiative heat loss during night was the key factor for site selection and human activities had no impact on bird's habitat.

The article discusses the results of a study which examines the prey selection of Common Kingfisher Alcedo atthis in northern Iberia. The authors utilized Savage's index to determine the presence of prey selection. The study revealed fish species selected by kingfishers as their prey including Bermejuela Acondrostoma arcasii, Bleak Alburnus alburnus, and Pyrenean Stone Loach Barbatula quignardi. It indicated that kingfisher selected pelagic species as their prey because of their accessibility and avoided bottom-dwelling species. The length, mean size, and age of fish prey are also described.

The movements of Mediterranean Yellow-legged Gulls Larus michahellis michahellis to the Bay of Biscay were analysed using sighting data of colour-ringed birds. A total of 1,270 sightings corresponding to 567 individuals was compiled over a 14-year period. Gulls originated mainly from colonies in the east of Iberia (52.7%), southern France (28.2%) and the Balearic Islands (17.3%). The proportion of the year spent in the Bay of Biscay decreased with age: first-year birds occurred on the coast of the Bay of Biscay throughout the year while older individuals were seen only from July to December. Overall, 39.7% of the birds were resighted in more than one calendar year. The return rate of adults and sub-adults was similar. The results confirm the importance of the Bay of Biscay as a non-breeding area (mainly in autumn and winter) for Yellow-legged Gulls from the Mediterranean, and suggest that this population should be considered as partially migratory. [ABSTRACT FROM AUTHOR]

During the winter, Bramblings Fringilla montifringilla are known for concentrating in huge communal roosts, normally situated along a NE–SW axis from west Russia to France in southern Europe. Irruptions of Bramblings in Iberia are rare and normally only in an attenuated form. Exceptionally, in November of 2010 a large roost of c 900,000 Bramblings formed in the Basque mountains of northern Iberia. We caught and ringed Bramblings from this roost from November 2010 to February 2011, and compared age and sex ratios, wing length and body mass to data reported in the literature. Overall, first-year birds comprised more than half the roost and the sex ratio in first-year birds was biased to females. This is in agreement with the prediction that first-year birds and females migrate to regions further south than males and adult birds. Wing length was constant across the season, but not body mass. Body mass was also negatively correlated with temperature and positively correlated with snowfall. [ABSTRACT FROM AUTHOR]

The article discusses research on the dynamics and structure of the wintering population of reed bunting Emberiza schoeniclus in northern Iberia. The reed bunting is described as a common Palearctic songbird that tends to select Iberia as one of its main wintering grounds. It is noted that male reed buntings are expected to be more abundant during mid-winter because they prefer to remain close to breeding areas during the winter season. Details concerning sampling site selection, bird subject collection, and wing length recording are reported. It is also mentioned that flight-associated morphology tend to vary seasonally and between bird age classes and sexes.

The article discusses research on the stopover behaviour of two bluethroat subspecies, Luscinia svecica namnetum and Luscinia svecica cyanecula, in northern Iberian region during the autumn season. The bird is described as a polytypic Holarctic passerine that tends to breed from Iberia. Details concerning selection of sampling area and bird subject collection are reported. The study reportedly used a Cochran-Mantel-Haenzel chi-square test for examining bird age class proportion and General Linear Models for analysing timing of passage.

The article discusses the findings of a study to determine whether or not Aquatic Warblers have the tendency to stop at suboptimal locations during poor weather. It notes that the research was conducted in the Jaizubia and Txingudi marshlands of northern Iberia where vegetation consisted mostly of reed beds. The results confirm that Aquatic Warblers are forced to land in Jaizubia's small habitats under rainy conditions, while optimal locations prove useful to them regardless of weather. The article mentions that Aquatic Warblers are endangered due to the loss of habitat.

The article provides information on a study which analyzed the potential variation in stopover behavior between dominant and subordinate individuals of the Northern Wheatear Oenanthe oenanthe, a territorial migrant bird species, at an offshore stopover area on the island of Helgoland, Germany. It also highlights the two strategies which subordinate birds could adopt in relation to their stopover duration. During their entire stopover in Helgoland, the behavior, individual features, and spatial distribution between subordinate and dominant Wheatears were compared. The researchers found that birds initiating an aggressive encounter were more likely to win.

The article discusses a research study which analyzed whether blackcaps Sylvia atricapilla stopping over in southern Iberia gain sufficient fuel in this region to be able to cross the Sahara in tropical Africa. Results revealed the lower fuel loads of blackcaps at Doñana in southern Iberia and their slower fuel disposition rate than at Loza in northern Iberia with similar stopover duration at both localities. The researchers observed longer estimated flight ranges in Loza than in Doñana, as well as the proportionally more abundance of recaptures at Loza. Observation showed the insufficiency of both sites for the blackcaps to refuel in order to reach tropical Africa.

The aim of this study was to investigate the relationship between breeding, moulting and fuel load of Common Crossbills Loxia curvirostra curvirostra inhabiting a Scots pine Pyrenean forest. Data were collected from two locations (Sierra de Uztarroz and Bigüezal) in northern Iberia by systematic mist netting between 2000 and 2008. Breeding females were detected in most months of the year except June, October and November, and with two main peaks, one in late winter (March), and another in the summer (August). Between years, reproduction was more variable in some months than in others, particularly in summer months. This suggests that breeding during the summer was more likely to be influenced by external factors and relatively opportunistic compared to winter breeding. Moulting adults of both sexes were captured during almost every month with a unimodal pattern peaking in June, similar to the pattern described for Mediterranean Crossbills. Moulting did not overlap with breeding, and our data do not support suspended moult patterns. Mean fat scores overall were low and, as was the case for body mass, showed little month-to-month variation. [ABSTRACT FROM AUTHOR]

The article presents a study on fuel load and potential flight ranges for common passerines that stopover at Txingudi marshlands in the western edge of the Pyrenees. The researchers used mist nets to capture the birds, which were ringed, aged and measured for subcutaneous fat scores, flight muscle and body mass. They also used the analysis of variance (ANOVA) to test whether fuel load differed between periods and species with different migration distances. They found that fuel load and flight ranges tended to be longer in autumn compared to spring.

The article discusses a study on the movements of first-year Yellow-legged Gulls or Larus michahellis lusitanius from the southeastern Bay of Biscay. It cites the use of darvic rings which allow researchers to conduct a more detailed analyses on movements of large gulls with consideration on the maximum distance where each individual was sighted. It suggests that a precise data on distribution of food availability can lead to a better understanding of the seasonal geographic distribution patterns of Yellow-legged Gulls in the southeastern Bay of Biscay.