0000000001310468
AUTHOR
Marcial Marín
Patterns of nestling provisioning by a single‐prey loader bird, Great TitParus major
Capsule Nestling provisioning rates depend on nestling age and number, and on time of season, but not on time of day. Aims To determine patterns of nestling provisioning, the effort made by the parents, and the factors which affect them. Methods Mechanical counters to determine food provisioning patterns in 229 Great Tit Parus major nests over 4 years. Results Feeding frequency per chick showed a linear increase with nestling age and total feeding frequency stabilized towards the end of the nestling period. The number of visits per nest increased linearly, while those per nestling decreased linearly with brood‐size. Feeding rates per nest declined throughout the breeding season parallel to …
Stable isotopes reveal differences in diet among reed bunting subspecies that vary in bill size
Reed bunting Emberiza schoeniclus subspecies vary considerably in bill size and shape and seem to be at an early stage of speciation, in which bill might be indirectly causing reproductive isolation. Hence, we evaluated whether bill size, as well as age and sex, are associated with foraging niche in three west European subspecies of reed bunting: the thin-billed schoeniclus, the intermediate-billed lusitanica and the thick-billed witherbyi. Blood sampling was undertaken at three sites in southwest Europe during the winter (when these subspecies co-occur), and stable isotope analyses (carbon and nitrogen) were performed to assess their foraging niches. Stable isotope analyses of potential fo…
Identifying the best fishing-suitable areas under the new European discard ban
Abstract The spatial management of fisheries has been repeatedly proposed as a discard mitigation measure. A number of studies have assessed the fishing suitability of an area based on units of by-catch or discard per unit effort. However, correct identification of fishing-suitable areas should assess biomass loss with respect to the benefits. This study therefore, proposes the analysis of by-catch ratios, which do represent benefit vs. loss and are standardized to a wide range of effort characteristics. Furthermore, our study proposes the use of two ratios: the proportion of total unwanted biomass out of the total catch as an indicator of the overall ecological impact, and the proportion o…
Habitat Preferences for Territory Selection by the Endangered Eastern Iberian Reed BuntingEmberiza Schoeniclus witherbyi
Summary. Given the 80% decline of the eastern Iberian reed bunting Emberiza schoeniclus witherbyi breeding population in recent decades, our aim was to identify the habitat components selected during territory establishment and to characterise the vegetation features that are positively or negatively selected at the territory scale. GLMM were used to explain the occurrence of territories in 11 wetlands. Fourteen variables with four vegetation dominance categories were analysed with respect to habitat composition, while occupancy of seven vegetation classes and 12 reed structural parameters were analysed with respect to habitat structure. The proportion of reed-cattails (Typha) measured by t…
Phenotypic Divergence among West European Populations of Reed Bunting Emberiza schoeniclus: The Effects of Migratory and Foraging Behaviours
[EN] Divergent selection and local adaptation are responsible for many phenotypic differences between populations, potentially leading to speciation through the evolution of reproductive barriers. Here we evaluated the morphometric divergence among west European populations of Reed Bunting in order to determine the extent of local adaptation relative to two important selection pressures often associated with speciation in birds: migration and diet. We show that, as expected by theory, migratory E. s. schoeniclus had longer and more pointed wings and a slightly smaller body mass than the resident subspecies, with the exception of E. s. lusitanica, which despite having rounder wings was the s…
Data from: Stable isotopes reveal differences in diet among reed bunting subspecies that vary in bill size
Reed bunting (Emberiza schoeniclus) subspecies vary considerably in bill size and shape and seem to be at an early stage of speciation, in which bill might be indirectly causing reproductive isolation. Hence, we evaluated whether bill size, as well as age and sex, are associated with foraging niche in three West European subspecies of reed bunting: the thin-billed schoeniclus, the intermediate-billed lusitanica and the thick-billed witherbyi. Blood sampling was undertaken at three sites in southwest Europe during the winter (when these subspecies co-occur), and stable isotope analyses (carbon and nitrogen) were performed to assess their foraging niches. Stable isotope analyses of potential …