Belly-soaking: A behavioural solution to reduce excess body heat in the Kentish plover Charadrius alexandrinus

During nesting, many temperate and tropical shorebirds are exposed to direct solar radiation and face heat stress. The aim of our study was to determine whether belly-soaking (wetting of ventral plumage) contributes to reducing excess body heat in Kentish plovers Charadrius alexandrinus. We captured incubating plovers on sunny days at their exposed nests, and placed them inside cloth bags at ground level in exposed sites for 5 min. This produced an increase in the ambient temperature experienced by the plovers, as well as an increase in the body temperature of the plovers. We simulated belly-soaking by submerging the ventral parts in water for about 10 s immediately after removing the birds from the bag. The body temperature of the plovers was lowered after simulated belly-soaking. Our results indicate that belly-soaking is a behavioural strategy to quickly reduce body temperature in heat-stressed plovers. © Japan Ethological Society and Springer 2008.Peer Reviewe

Reuse of nesting scrapes by Kentish Plovers

We studied reuse of nesting scrapes within breeding seasons by Kentish Plovers (Charadrius alexandrinus) in an inland lake of southern Spain over six years. Overall, 5.6% of original nests were reused at least once. We tested whether nest reuse is adaptive, but found no differences in breeding success between those pairs that reused nests and those that did not. We also tested whether nest reuse should be more frequent when scrapes are difficult to excavate than when it is easier to excavate them, and found that nests on hard substrates were more frequently reused than nests on soft substrates, and that nest reuse was more frequent in the second half of the season, when the nesting substrate is harder, than in the first half of the season. This suggests that nest reuse may save Kentish Plovers some energy.Peer Reviewe

Greater flamingos Phoenicopterus roseus are partial capital breeders

Capital breeding refers to a strategy in which birds use body stores for egg formation, whereas income breeders obtain all resources for egg formation at breeding sites. Capital breeding should occur more in large-bodied species because the relative cost of carrying stores for egg formation becomes smaller with increasing body size. Based on a comparison between stable isotopes of carbon and nitrogen in potential prey at wintering sites and eggs, we examined whether greater flamingos use nutrients stored earlier in the year for egg production. Our results suggest that the greater flamingo is a partial income breeder, since prey for egg formation were obtained both in overwintering sites and at the breeding site. This may be because there are selective pressures for nesting females to lay soon after arriving at the breeding site, which may be facilitated by arriving at the breeding site with developed ovarian follicles. © 2011 The Authors.Peer Reviewe

Sex-related seasonal differences in the foraging strategy of the Kentish Plover

In species of birds with biparental care, each sex may have its own energy requirements and/or schedule for feeding, possibly leading the sexes to differ in foraging strategy. In estuaries, shorebirds such as the Kentish Plover (Charadrius alexandrinus alexandrinus) may forage on intertidal mudflats and in adjacent su- pratidal habitats during winter as well as during the breeding season. In this study, we analyzed the diet, use of foraging habitat, food-intake rate (biomass ingested per unit time), and time allocated to foraging by male and female Kentish Plovers at both seasons in an estuary near Cádiz, Spain, where intertidal mudflats and adjacent salt works are the main habitats for foraging. The plovers’ main prey was the ragworm (Nereis diversicolor), an intertidal polychaete that supplied more than 80% of the biomass consumed at each season. During the breeding season, both sexes increased their intake rate and decreased their daylight foraging time. By increasing the diurnal intake rate during the breeding season, the birds minimized their time spent foraging on the intertidal mudflats, allowing them to maximize the time for activities associated with breeding in the adjacent salt works. Therefore, the plovers solved the conflict between foraging on the mudflats and breeding in the salt works by shortening the foraging time on the mudflats, minimizing time away from the nesting areas. The sexes differed in the daylight time allocated to foraging, with females spending 2 hr less on foraging and concentrating their feeding activity into the central hours of low tideEn especies de aves con cuidado biparental, cada sexo puede tener sus propios requerimientos de energía y/o esquema de tiempo para la alimentación, lo cual podría conducir a diferencias en las estrategias de alimentación entre ambos sexos. En los estuarios, las especies de playeros como Charadrius alexandrinus pueden forrajear en fangos intermareales y en hábitats supramareales adyacentes tanto durante el invierno así como du- rante la época reproductiva. Aquí, analizamos la dieta, el uso de hábitat de forrajeo, la tasa de ingestión (biomasa ingerida por unidad de tiempo) y el tiempo dedicado al forrajeo por el macho y la hembra de C. alexandrinus du- rante ambas temporadas en una zona estuarina donde los fangos intermareales y las salinas adyacentes son las principales áreas de alimentación. La principal presa para C. alexandrinus fue un poliqueto (Nereis diversicolor), una presa intermareal que suplió más del 80% de la biomasa consumida en cada estación. Ambos sexos incremen- taron sus tasas de alimentación durante la época reproductiva, y disminuyeron sus tiempos diurnos de forrajeo. Por el incremento de la tasa de ingestión durante la época reproductiva, las aves minimizaron el tiempo que pasaron en los fangos intermareales, lo que les permitió maximizar el tiempo dedicado a las actividades de reproducción en las salinas adyacentes. Por lo tanto, el conflicto entre alimentarse en los fangos versus el desarrollo de las ac- tividades de reproducción (en las salinas), fue resuelto acortando el tiempo en los fangos, minimizando el tiempo fuera de las zonas de nidada. Hubo diferencias relacionadas con el sexo en el tiempo diurno dedicado al forrajeo: las hembras dedicaron dos horas menos a la alimentación y concentraron su actividad de alimentación en las horas centrales de la marea baja

Brood desertion by female shorebirds: A test of the differential parental capacity hypothesis on Kentish plovers

The aim of this study was to examine whether the energetic costs of reproduction explain offspring desertion by female shorebirds, as is suggested by the differential parental capacity hypothesis. A prediction of the hypothesis is that, in species with biparental incubation in which females desert from brood care after hatching, the body condition of females should decline after laying to a point at which their body reserves are too low for continuing parental care. We tested this prediction on Kentish plovers (Charadrius alexandrinus) in which both sexes incubate but the females desert from brood care before the chicks fledge. We found no changes in either the body masses or body compositions of both individual male and female plovers from early incubation and throughout early chick rearing. Furthermore, the timing of brood desertion by females was not affected by their body condition. Neither did we find gender differences in the energetic costs of incubation. There were no differences in the timing of brood desertion between experimental and control females in an experiment in which we lengthened or shortened the duration of incubation by one week. These results indicate that energetic costs do not explain offspring desertion by female Kentish plovers and that the needs of chicks for parental care rather than cumulative investment by females is what determines the timing of brood desertion.Peer Reviewe

A trade-off between overheating and camouflage on shorebird eggshell colouration

In ground-nesting birds egg colour and appearance may have evolved due to opposite selection pressures. Pigmentation and spottiness make the eggs darker and have been suggested to improve camouflage. However darker and more spotted eggs may reach higher temperatures when not attended by adults and receiving direct sunlight, which may be lethal for embryos. Some authors suggested that this trade-off may not exist because eggshell pigments mainly reflect in the infrared region of the solar spectrum, but have not considered that wavelengths in the visible part of the spectrum may also contribute to overheating. To test the occurrence of a trade-off between camouflage and overheating of eggs, we took digital images to analyse colour and camouflage in 93 nests of four shorebird species (two stilts and two plovers) in two regions (tropical and mediterranean sites). We predicted that these species (closely related) may have evolved different eggshell designs depending on solar radiation, which is supposed to be stronger in the Tropics. To record egg temperatures, we placed Japanese quail eggs in natural nests of shorebirds, and registered temperatures using a datalogger. We found that darker and more spotted eggs reached higher temperatures than lighter ones, and that after controlling for environmental temperatures, eggs overheated more in the Tropics, likely because of a more intense solar radiation. We also found that tropical shorebirds’ eggshells have darker spots and lighter backgrounds. Overall, darker eggs were better camouflaged. Taken together, our results show that the benefits of increasing pigmentation of eggshell backgrounds and spottiness for a better camouflage are counteracted by the increased risks of overheating when eggs remain exposed to direct solar radiation.Peer reviewe

Dynamics of the family of c-iterative methods

In this paper, the dynamics of the family of c-iterative methods for solving nonlinear equations are studied on quadratic polynomials. A singular parameter space is presented to show the complexity of the family. The analysis of the parameter space allows us to find elements of the family that have bad convergence properties and also other ones with very stable behaviour. These schemes correspond to values of c in different small regions of the parameter space.Supported by Ministerio de Ciencia y Tecnologia MTM2011-28636-C02-02. The first and fourth authors were also partially supported by P11B2011-30 (Universitat Jaume I), the second and third authors were also partially supported by Vicerrectorado de Investigacion, Universitat Politecnica de Valencia PAID-06-2010-2285.Campos, B.; Cordero Barbero, A.; Torregrosa Sánchez, JR.; Vindel, P. (2015). Dynamics of the family of c-iterative methods. International Journal of Computer Mathematics. 92(9):1815-1825. https://doi.org/10.1080/00207160.2014.893608S1815182592

Ardeola, a scientific journal of ornithology: cooperative survivorship within the red queen game

Editorial.-- et al.[EN]: Ardeola is the scientific journal of the Spanish Ornithological Society. We analyse historical changes in citation, topics and foreign authorship of articles published in Ardeola from its first publication in 1954 up to last year, 2015, to test to what extent the persistence of the journal during the last 61 years has been due to support of authors, Society members, readers, editors or the whole ornithological community. Analyses were done within the context of the Red Queen game played by scientific journals competing for the best and more cited articles. The impact factor of Ardeola has increased from 1985 onwards both in absolute and relative terms. Thematic changes have followed trends of the general ornithological literature, without the journal specialising in particular topics or geographical regions. Foreign authorship decreased from 1954 up to the end of the 20 century, subsequently increasing again, a trend fuelled by coverage by Current Contents and the JCR, the establishment of English as the language of publication and recent Internet access through the BioOne platform. Ardeola is a traditional scientific journal, backed by a scientific society, whose future will be guaranteed by a reputation for rigour and quality sought by authors, reviewers and editors, supported by the members of the Spanish Ornithological Society and retaining its original objective: 'to be a journal at the level of the best..., looking for a strong collaboration with foreign authors to promote the benefit of the Ornithology'.[ES]: Ardeola es la revista científica de la Sociedad Española de Ornitología (SEO/BirdLife). Analizamos los cambios históricos en citación, temática y contribución de autores extranjeros a los artículos publicados en Ardeola desde sus inicios en 1954 hasta el año pasado, 2015, con el objetivo de evaluar si el mantenimiento de la revista a lo largo de los últimos 61 años se ha debido al apoyo de los autores, de los miembros de SEO/BirdLife, de los lectores, de los editores de la revista, o de los ornitólogos en general. Los análisis de este mantenimiento se realizan en el contexto del juego de la reina roja en el que están implicadas las revistas científicas, que compiten por publicar los mejores artículos más citados. El factor de impacto de Ardeola ha aumentado desde 1985 en adelante, tanto en términos absolutos como relativos. En la actualidad es de 0,6–0,8, situándose en el tercer cuartil de las revistas de ornitología cubiertas por el Journal Citation Reports (JCR). Los cambios temáticos han seguido en general los del resto de la literatura ornitológica, sin especializarse en temas o áreas geográficas particulares. La proporción de autores extranjeros disminuyó desde 1954 hasta finales del siglo pasado, recuperándose a continuación a niveles del 30%–40%, una tendencia que sin duda se ha acelerado por la cobertura de Ardeola por Current Contents y el JCR, el establecimiento del inglés como idioma de publicación y el acceso reciente por Internet a través de BioOne. Ardeola es una revista científica clásica, sostenida por una sociedad científica, cuyo futuro será garantizado por el sello riguroso de calidad mantenido por autores, revisores y editores, y mantenido por los miembros de SEO/BirdLife con el mismo espíritu con el que fue creada in 1954: ‘para ser una revista del nivel de las mejores…, buscando una intensa colaboración con autores extranjeros para promover el beneficio de la Ornitología’.Peer Reviewe

CMMSE2017: On two classes of fourth- and seventh-order vectorial methods with stable behavior

[EN] A family of fourth-order iterative methods without memory, for solving nonlinear systems, and its seventh-order extension, are analyzed. By using complex dynamics tools, their stability and reliability are studied by means of the properties of the rational function obtained when they are applied on quadratic polynomials. The stability of their fixed points, in terms of the value of the parameter, its critical points and their associated parameter planes, etc. give us important information about which members of the family have good properties of stability and whether in any of them appear chaos in the iterative process. The conclusions obtained in this dynamical analysis are used in the numerical section, where an academical problem and also the chemical problem of predicting the diffusion and reaction in a porous catalyst pellet are solved.This research was partially supported by Ministerio de Economia y Competitividad MTM2014-52016-C02-2-P and Generalitat Valenciana PROMETEO/2016/089.Cordero Barbero, A.; Guasp, L.; Torregrosa Sánchez, JR. (2018). CMMSE2017: On two classes of fourth- and seventh-order vectorial methods with stable behavior. Journal of Mathematical Chemistry. 56(7):1902-1923. https://doi.org/10.1007/s10910-017-0814-0S19021923567S. Amat, S. Busquier, Advances in Iterative Methods for Nonlinear Equations (Springer, Berlin, 2016)S. Amat, S. Busquier, S. Plaza, Review of some iterative root-finding methods from a dynamical point of view. Sci. Ser. A Math. Sci. 10, 3–35 (2004)S. Amat, S. Busquier, S. Plaza, A construction of attracting periodic orbits for some classical third-order iterative methods. Comput. Appl. Math. 189, 22–33 (2006)I.K. Argyros, Á.A. Magreñn, On the convergence of an optimal fourth-order family of methods and its dynamics. Appl. Math. Comput. 252, 336–346 (2015)D.K.R. Babajee, A. Cordero, J.R. Torregrosa, Study of multipoint iterative methods through the Cayley quadratic test. Comput. Appl. Math. 291, 358–369 (2016). doi: 10.1016/J.CAM.2014.09.020P. Blanchard, The dynamics of Newton’s method. Proc. Symp. Appl. Math. 49, 139–154 (1994)F.I. Chicharro, A. Cordero, J.R. Torregrosa, Drawing dynamical and parameters planes of iterative families and methods. Sci. World J. 2013, Article ID 780153 (2013)C. Chun, M.Y. Lee, B. Neta, J. Džunić, On optimal fourth-order iterative methods free from second derivative and their dynamics. Appl. Math. Comput. 218, 6427–6438 (2012)A. Cordero, E. Gómez, J.R. Torregrosa, Efficient high-order iterative methods for solving nonlinear systems and their application on heat conduction problems. Complexity 2017, Article ID 6457532 (2017)A. Cordero, J.R. Torregrosa, Variants of Newton’s method using fifth-order quadrature formulas. Appl. Math. Comput. 190, 686–698 (2007)R.L. Devaney, An Introduction to Chaotic Dynamical Systems (Addison-Wesley Publishing Company, Reading, 1989)P.G. Logrado, J.D.M. Vianna, Partitioning technique procedure revisited: formalism and first application to atomic problems. Math. Chem. 22, 107–116 (1997)C.G. Jesudason, I. Numerical nonlinear analysis: differential methods and optimization applied to chemical reaction rate determination. Math. Chem. 49, 1384–1415 (2011)Á.A. Magreñán, Different anomalies in a Jarratt family of iterative root-finding methods. Appl. Math. Comput. 233, 29–38 (2014)M. Mahalakshmi, G. Hariharan, K. Kannan, The wavelet methods to linear and nonlinear reaction-diffusion model arising in mathematical chemistry. Math. Chem. 51(9), 2361–2385 (2013)K. Maleknejad, M. Alizadeh, An efficient numerical scheme for solving Hammerstein integral equation arisen in chemical phenomenon. Proc. Comput. Sci. 3, 361–364 (2011)B. Neta, C. Chun, M. Scott, Basins of attraction for optimal eighth-order methods to find simple roots of nonlinear equations. Appl. Math. Comput. 227, 567–592 (2014)M.S. Petković, B. Neta, L.D. Petković, J. Džunić, Multipoint Methods for Solving Nonlinear Equations (Elsevier, Amsterdam, 2013)R.C. Rach, J.S. Duan, A.M. Wazwaz, Solving coupled Lane–Emden boundary value problems in catalytic diffusion reactions by the Adomian decomposition method. Math. Chem. 52(1), 255–267 (2014)R. Singh, G. Nelakanti, J. Kumar, A new effcient technique for solving two-point boundary value problems for integro-differential equations. Math. Chem. 52, 2030–2051 (2014

Quail eggs in artificial nests change their coloration when exposed to ambient conditions: implication for studies on nest predation

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.This study was funded by grant CGL2017-83518-P from Ministerio de Economia, Industria y Competitividad, Spain, with EU-ERDF financial support. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript