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[ES] Este conjunto de datos, generado en el marco del proyecto CAMNID: CGL2017-83518-P, Plan Nacional I+D+i, contiene información visual sobre huevos, nidos y comportamiento durante la incubación de diferentes especies de aves de litoral (shorebirds). Permite la realización de análisis de coloración y moteado, entre otros, para las especies en estudio. Asimismo, se proporcionan secuencias de imágenes de monitorización de diversos nidos de estas especies a lo largo de 3 horas (entre las 12:00 y las 15:00) junto con las condiciones ambientales durante la vigilancia. Esto permite la realización de estudios de los comportamientos de estas aves durante la incubación, abriendo la posibilidad de estudiar diversos mecanismos de mitigación de estrés térmico o las alternancias parentales macho/hembra durante la incubación en función de las condiciones ambientales, [EN] This dataset, generated within the framework of the CAMNID project: CGL2017-83518-P, Plan Nacional I+D+i, contains visual information on eggs, nests, and incubation behavior of various shorebird species. It enables color and spotting pattern analyses, among other studies, for the species included. Additionally, it provides image sequences monitoring various nests of these species over a 3-hour period (from 12:00 to 15:00) along with the environmental conditions during the surveillance. This allows for studies of the birds' behavior during incubation, opening the possibility to study mechanisms of thermal stress mitigation and male/female parental alternation during incubation based on environmental conditions.

The dataset includes a file with information relative to blood chemistry values (16 parameters), body measurementes (2 parameters), moulting stage (3 categories), body-mass index (1 parameter) and sex (2 categories) of black-necked grebes (669 individuals) during the moulting periods (late August-early December) of 2008 and 2009 at the Odiel marshes, southwestern Spain: (i) File : Blood chemistry values and body measurements of black-necked grebes according to moulting stage and sex.

Predation is one of the main causes of nest failure in birds. In order to overcome this, many species lay cryptic eggs, which enhances camouflage through either background matching or shape disruption, among other mechanisms. Despite this, ground-nesting birds still suffer high nest predation rates. One possibility to alleviate this could be to soil the eggs with particles of material surrounding nests, improving the camouflage. Indeed, it has been suggested that egg soiling is a mechanism of egg protection, but it remains to be demonstrated whether egg soiling is a strategy used by birds or is an unintentional by-product after incubating adults enter nests with dirty feet, legs and/or plumage. In this study, we analysed images from infra-red camera traps placed beside Pied Avocet Recurvirostra avosetta nests, in which we had previously cleaned dirty eggs and provided mud with which the adults might have soiled the eggs, and we found no evidence of deliberate egg soiling in this case. There was a slight improvement (not statistically significant) in the camouflage of soiled avocet eggs in comparison to clean eggs, but only in one of two studied nesting sites in which the eggs were more soiled. Although egg soiling may result in improved camouflage, future studies should address its potential costs to establish why it has not apparently evolved as a deliberate strategy to improve egg camouflage in nesting shorebirds.

Many studies addressing the use of nest materials by animals have focused on only one factor to explain its function. However, the consideration of more than one factor could explain the apparently maladaptive choice of nest materials that makes the nests conspicuous to predators. Here, we tested experimentally whether there is a trade-off in the use of nest materials between the risks of egg predation and overheating when the eggs are not attended by adults in the ground-nesting Kentish plover, Charadrius alexandrinus. For this, we added into nests materials differing in their thermal properties and coloration, thus affecting rates of egg heating and camouflage. Before manipulations, adults had selected light materials that matched worse egg coloration than the microhabitat, likely to buffer the risk of egg overheating. However, the adults did not keep the lightest experimental materials, probably because camouflage worsened. In all nests, adults removed most of the experimental materials independently of their properties, so that egg camouflage returned to the original values within a week of the experimental treatments. Although the thermal environment may affect the choice of nest materials by the plovers, at our study sites it was not likely too stressful as to determine the acceptance of the lightest experimental materials.

Quail eggs have been widely used in field experiments, mainly to study factors associated with the risk of nest predation. Some shortcomings of using quail eggs in this type of study have been previously addressed (e.g., these eggs might be too big for some predators of eggs of small birds). Here, we show experimental evidence of another shortcoming of the use of these eggs in field experiments. Quail eggs exposed to sunlight rapidly faded in colour after three days, both in the visible and UV spectra, and this change was related to the amount of solar radiation received. This caused changes in the camouflage of the eggs, which may be perceived by predators with different visual systems (dichromatic, trichromatic, and tetrachromatic (for both violet- and UV-sensitive species)). Therefore, the results of field studies of nest predation using quail eggs might be questioned in those cases in which the camouflage has been altered due to the rapid changes in coloration, as this can affect the resulting predation rates. We recommend that researchers planning to use quail eggs should perform a prospective assessment of changes in coloration of eggs exposed to environmental conditions in the nest sites used by the target species.

Quail eggs have been widely used in field experiments, mainly to study factors associated with the risk of nest predation. Some shortcomings of using quail eggs in this type of study have been previously addressed (e.g., these eggs might be too big for some predators of eggs of small birds). Here, we show experimental evidence of another shortcoming of the use of these eggs in field experiments. Quail eggs exposed to sunlight rapidly faded in colour after three days, both in the visible and UV spectra, and this change was related to the amount of solar radiation received. This caused changes in the camouflage of the eggs, which may be perceived by predators with different visual systems (dichromatic, trichromatic, and tetrachromatic (for both violet- and UV-sensitive species)). Therefore, the results of field studies of nest predation using quail eggs might be questioned in those cases in which the camouflage has been altered due to the rapid changes in coloration, as this can affect the resulting predation rates. We recommend that researchers planning to use quail eggs should perform a prospective assessment of changes in coloration of eggs exposed to environmental conditions in the nest sites used by the target species

Overview: We assessed the role of age and disease activity as new factors contributing to establish the risk of progressive multifocal leucoencephalopathy in multiple sclerosis patients treated with natalizumab in 36 University Hospitals in Europe. We performed the study in 1,307 multiple sclerosis patients (70.8% anti-John Cunninghan virus positive antibodies) treated with natalizumab for a median time of 3.28 years. Epidemiological, clinical, and laboratory variables were collected. Lipid-specific IgM oligoclonal band status was available in 277 patients. Factors associated with progressive multifocal leucoencephalopathy onset were explored by uni- and multivariate logistic regression. Results: Thirty-five patients developed progressive multifocal leucoencephalopathy. The multivariate analysis identified anti-John Cunninghan virus antibody indices and relapse rate as the best predictors for the onset of this serious opportunistic infection in the whole cohort. They allowed to stratify progressive multifocal leucoencephalopathy risk before natalizumab initiation in individual patients [area under the curve (AUC) = 0.85]. The risk ranged from <1/3,300 in patients with anti-John Cunninghan virus antibody indices <0.9 and relapse rate >0.5, to 1/50 in the opposite case. In patients with lipid-specific IgM oligoclonal bands assessment, age at natalizumab onset, anti-John Cunninghan virus antibody indices, and lipid-specific IgM oligoclonal band status predicted progressive multifocal leucoencephalopathy risk (AUC = 0.92). The absence of lipid-specific IgM oligoclonal bands was the best individual predictor (OR = 40.94). The individual risk ranged from <1/10,000 in patients younger than 45 years at natalizumab initiation, who showed anti John Cunningham virus antibody indices <0.9 and lipid-specific IgM oligoclonal bands to 1/33 in the opposite case. Conclusions: In a perspective of personalized medicine, disease activity, anti-lipid specific IgM oligo

There are two main methods to extract pigments from avian eggshells. There are those using strong acids (e.g. sulphuric, hydrochloric or formic), that allow for a quantification of pigment concentrations but with which samples are destroyed. Alternatively, there are methods employing weaker acids (e.g. acetic), with which samples are not destroyed, although pigment concentrations may not be quantified and only their presence is detected. In some cases, there may be a need to quantify pigments in samples in which the pigments have already been detected. Here, we assess whether the quantity of pigments extracted from eggshells using a strong acid is affected by previous treatment of eggshells with a weak acid. For this, we used eggshells of Kentish Plovers Charadrius alexandrinus and domestic Japanese Quails Coturnix japonica, and aliquots of individual eggshells treated either with both acids (first applying a weak acid and then a strong acid) or only with the strong acid. Quantities of extracted protoporphyrin and biliverdin (the main eggshell pigments) were lower when using a strong acid after application of a weak acid. However, there were significant positive correlations between the quantities of pigments extracted using the two methods, suggesting that eggshell samples used to determine pigment presence may still be usable to quantify pigment concentrations using a strong acid. - Gómez, J., Ramo, C., Canales, J.A., García, I.M., Castro, M., Pérez-Hurtado, A. & Amat, J.A. (2020). A comparative assessment of pigment extraction from avian eggshells using two analytical protocols.

Many studies addressing the use of nest materials by animals have focused on only one factor to explain its function. However, the consideration of more than one factor could explain the apparently maladaptive choice of nest materials that make nests conspicuous to predators. We experimentally tested whether there is a trade-off in the use of nest materials between the risks of egg predation versus protection from overheating. We studied the ground-nesting Kentish plover, Charadrius alexandrinus, in southern Spain. We added materials differing in thermal properties and coloration to the nests, thus affecting rates of egg heating, nest temperature and camouflage. Before thesemanipulations,adultsselectedmaterialsthatwerelighter than the microhabitat, probably to buffer the risk of egg overheating. However, the adults did not keep the lightest experimental materials, probably because they reduced camouflage, and this could make the nests even more easily detectable to predators. In all nests, adults removed most of the experimental materials independently of their properties, so that egg camouflage returned to the original situation within a week of the experimental treatments. Although the thermal environment may affect the choice of nest materials by plovers, ambienttemperatureswerenotsohighatourstudysiteastodetermine the acceptance of the lightest experimental materials.