BUSCADOR RECOLECTA

Data file includes information about identity of each sampled individual, the species id, nest type, age, biometric measurements, the mean of the antagonistic halos shown against each 9 indicator bacteria, the antagonistic activity (average values of the width of antagonistic halos (mm) when tested against each of the nine indicator bacteria), the antagonistic range (Shannon index of the antagonistic activity) and the total density of bacteria on the gland., Ester Martínez Renau was financed by a predoctoral contract PRE2018-085378) while the whole research group received funds from the projects CGL2017-83103-P, PID2020-117429GB-C21 and PID2020-117429GB-C22, funded by the Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación/10.13039/501100011033 and by “Fondo Europeo de Desarrollo Regional, a way of making Europe, Peer reviewed

[How to contribute] For any problems downloading the data or for additional information, please send us an email and we will provide you with the necessary information. We would also appreciate your feedback regarding potential errors., [Ethics statement] All procedures were conducted according to relevant Spanish national (Decreto 105/2011, 19 de abril) and regional guidelines. Necessary permits for hoopoe manipulation were provided by Consejería de Medio Ambiente de la Junta de Andalucía, Spain (Ref: SGYB/FOA/AFR/CFS and SGMN/GyB/JMIF). All applicable guidelines for the care and use of animals were followed., We discuss the potential adaptive functions of laying optimistic clutch sizes that hatch asynchronously in hoopoes, a bird species with frequent sibling cannibalism. The production of extra eggs could serve as insurance against hatching failures, while the surplus hatchlings can be used as food and increase the probability of survival of their older siblings. Two experiments were conducted to explore the adaptative functions of producing extra offspring, one involving food supplementation during the egg-laying period, and the other manipulating brood size and hatching span. Results showed that females with extra food laid one more egg on average and that adding an extra egg that hatched the last increased sibling cannibalism and fledging success. These findings suggest that hoopoes are able to recover part of the cost of producing large clutches by consuming surplus chicks., The research group received funds from the projects PID2020-117429GB-C21 and PID2020-117429GB-C22, funded by the Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación/10.13039/501100011033 and by “Fondo Europeo de Desarrollo Regional, a way of making Europe”. We also benefited from facilities, including an apartment, provided by the city authorities of Guadix., Peer reviewed

Data used in "Avian sibling cannibalism: Hoopoe mothers regularly use their last hatched nestlings to feed older siblings", Peer reviewed

Nest materials used by animals can have profound effects on developing offspring. They can modify the bacterial and parasitic environment of the nest, and can influence parental investment through sexual signalling processes. In spotless starlings, Sturnus unicolor, green plants and feathers are known nest materials with such functions. The aim of our study was to experimentally assess their influence on nestlings’ telomere length and attrition, which are good predictors of their survival prospects. In a full-factorial experiment, we explored these effects in two different populations, together with the potential effects of hatching date, ectoparasitism, bacterial environment and nestling growth. Telomere length and attrition largely depended on population identity and hatching date. After correcting for these effects, the addition of feathers resulted in higher rates of telomere attrition. The addition of plants did not affect nestling telomeres in general, but did in interaction with location: in Hueneja, the experimental addition of green plants resulted in longer telomeres. Feather pigmentation also did not affect telomere length or attrition in general, but did in interaction with location: in Hueneja, the experimental addition of unpigmented feathers resulted in nestlings with longer telomeres and lower attrition rates. Moreover, prevalence of staphylococci on the skin of 8-day-old nestlings was negatively related to telomere lengths of fledglings. Taken together, these results suggest a direct link between nest material composition and nestling telomere length and dynamics. This relationship could be partially mediated by the antimicrobial and/or antiparasitic properties of nest materials or by sexual signalling, Funding was provided by the Spanish Ministerio de Economia y Competitividad and European funds (FEDER) (CGL2013-48193-C3-1-P, CGL2013-48193-C3-2-P, CGL2012-30759, CGL2015-65055-P). J.M.P., G.T. and M.R.R. were supported respectively by Juan de la Cierva, Ramón & Cajal and Talentia postdoctoral contracts., Peer reviewed

Support by funding was provided by Spanish Ministerio de Ciencia e Innovación, European funds (FEDER) (CGL2009-14006, CGL2010-19233-C03-01, CGL2010-19233-C03-03, CGL2013-48193-C3-1-P, CGL2013-48193-C3-2-P) and Junta de Andalucía (P09-RNM-4557). AM-G had a predoctoral grant from the Junta de Andalucía (P09-RNM-4557)., Peer reviewed

Sexually selected signals reliably reflect individual phenotypic or genetic quality and, thus, survival prospects of holders. Telomere length is considered a good predictor of life expectancy and, consequently, exploring the links between telomere length and sexually selected traits is much needed to better understand the mechanisms that maintain the honesty of sexual signals. We manipulated the length of throat feathers in spotless starling (Sturnus unicolor) males (a sexually selected signal) before reproduction and explored its effects on telomere shortening and breeding performance in subsequent reproductive events. We did not detect an effect of the feathers clipping manipulation, but males with longer throat feathers before the experiment had shorter telomeres that also shortened more slowly than those of males with shorter throat feathers did. Moreover, length of throat feathers of males before manipulation was positively related to hatching success of second clutches. Thus, correlative but not experimental results support the expected associations between sexually selected signals, telomeres and reproduction. We discuss such results in scenarios of sexual selection where feather length reflects, but does not directly cause, telomere attrition and enhanced reproductive success. Males with longer throat feathers might be older, more experienced males (i.e., with shorter telomeres), able to buffer telomere shortening between reproductive events. Because of the absence of experimental effects, differential incubation effort of females cannot explain the detected association with hatching success, but other sexually selected traits that covary with throat-feather length could be responsible. Exploring those physiological and/or morphological characteristics related to throat-feather length should therefore be the matter of future research, This work was supported by the currently named Ministerio de Ciencia, Innovación y Universidades and European (FEDER) funds (CGL2013-48193-C3-1-P, CGL2017-83103-P, CGL2017-89063-P, CGL2015-65055-P and PGC2018-095704-B-100). MAG was financed by a predoctoral contract (BES-2014-068661) from the Spanish Ministerio de Economía y Competitividad, and GT by the Ramón y Cajal Programme., Reproductive data; Telomere data, Peer reviewed

Data file includes (i) average values of melanised (M) and non-melanised (NM) feather wear of nestling birds that grew in different nests. The file also included (ii) information of feather mass degradability of nestlings and adult birds from different nests and species estimated as the olipeptide concentration (μg x mL1) of tubes containing 4mL of PBS buffer and a colony Bacillus licheniformis D13 after 21 days of incubation at 37 ºC in constant agitation at 120 rpm in an orbital agitator (VWR, Spain). The third excel sheet contain information of bacterial loads in terms of terms of mesophilic bacteria (TSA), Enterobacteriaceae (HK), Staphylococcus (VJ), and Enterococcus (KF), and average wear of melanised (M) and non-melanised (NM) wing feathers of nestlings that grew in the same nests where bacterial loads were estimated. The last excel file contain information on feather wear of melanised and non-melanised feathers of each sampled nestlings and adult. All these data were collected the Guadix region (southern Spain) and used to perform the statistical analyses in Tables 2 and 3 in Azcárate et al. 2020 (Doi: 10.1111/jav.02320)., This work was supported by the currently named Ministerio de Ciencia, Innovación y Universidades and European (FEDER) funds (CGL2013-48193-C3-1-P, CGL2013-48193-C3-2-P, CGL2013-48193-C3-3-P, CGL2017-83103-P). MAG and SDL were financed by predoctoral contracts (BES-2014-068661, BES-2014-069116) from the Spanish Ministerio de Economía y Competitividad., Peer reviewed

Study area and study species The study was conducted during the years 2015, 2016 and 2017 in a south-eastern region of Spain (Hoya de Guadix, 37º15’N, 3º01’W), where nest-boxes attached to tree trunks or walls at 3–4 m above-ground are available for starlings to breed in (for further information on the study area see Soler et al. (2017)). In the studied starling population, the reproductive season starts in early April and most individuals lay a second clutch during May-June. The most common clutch size is 62 plants to the nest, which have been shown to have antimicrobial-beneficial functions4-5 eggs. Here, we will focus on the colouration of the base of the beak, a trait with a more marked sexual differentiation as we can see in its reflectance at different wavelengths (Fig. 1). Fieldwork and experimental procedure In this population, courtship activity (e.g. singing, introducing fresh green plants and feathers in nest boxes) starts in February, more than one month before egg laying (pers. obs.). During this period, some birds roost in nest-boxes and we take advantage ofthis fact for conducting yearly bird trapping sessions in the study area (twice a year between February and mid-March). One hour before dawn, we closed the entrance of all nest boxes in the study area, and immediately after dawn, we captured by hand all individuals found roosting inside. Captured birds were kept individually in clean cotton bags hanging from a stick to keep birds quiet, and were released immediately after sampling. The maximum time that a captured starling was in the bag did never exced three hours. We explored the possible effect of time that birds were kept in the bag on bird colouration and body condition measures of the males that we recaptured by classifying them as being kept in the bag less than 1 hour (N(males) = 10), between 1 and 2 hours (N = 5), and between 2 and 3 hours (N = 7). After controlling for the effect of date of first and last capture, time between captures, treatment and size of throat feathers in the first capture, results showed that retaining time 184 in first captures did not significantly affect blue, red-yellow, or brightness colouration of the beak of males (F1,15 < 2.66, P > 0.124), nor body condition (F1, 10 = 2.19, P = 0.170) in subsequent captures. It neither had any apparent long-term consequences (see Ruiz-Rodríguez et al. (2015)), nor imply apparent negative effects on breeding performance of captured birds (Soler et al. 2008), This work was supported by the currently named Ministerio de Ciencia,es and European (FEDER) funds (GL2013C-48193-C3-1-P, CGL2017-83103-P Innovación Universidad, CGL2017-89063-P). MAG was financed by a predoctoral contract (BES-2014-068661) from the Spanish Ministerio de Economía y Competitividad, and GT by the Ramón y Cajal Programme, Peer reviewed

It contains data collected in Guadix, Granada (southeast Spain) in 2019, in the framework of a research to evaluate the effects of chemical and auditory cues of hoopoes (Upupa epops) in repellence and attraction of blood-feeding flies. Dataset includes number of mosquitoes, blackflies and biting midges collected in insect traps in the field in four habitat types and two sampling periods, in relation to different chemical and auditory stimuli derived from nestlings of this bird species., Financial support was provided by grants from the Spanish Ministerio de Economía, Industria y Competitividad (CGL2017-89063-P, CGL2017-83103-P). GT was also supported by the Ramón y Cajal Programme. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI)., Peer reviewed