Gustavo Tomás

Estacion Experimental de Zonas Aridas

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Santiago Merino

Museo Nacional de Ciencias Naturales

Juan Moreno

Museo Nacional de Ciencias Naturales

Judith Morales

Museo Nacional de Ciencias Naturales

Josué Martínez‐de la Puente

Estación Biológica de Doñana

Elisa Lobato

Centre d'Écologie Fonctionnelle et Évolutive

Juan José Soler

Estacion Experimental de Zonas Aridas

Magdalena Ruiz‐Rodríguez

Estacion Experimental de Zonas Aridas

Cristina Ruiz‐Castellano

Estacion Experimental de Zonas Aridas

Javier Martı́nez

Universidad de Alcalá

Juan José Sanz

Museo Nacional de Ciencias Naturales

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Consejo Superior de Investigaciones Científicas

Museo Nacional de Ciencias Naturales

Estacion Experimental de Zonas Aridas

Universidad de Granada

National Research Council

Google (United States)

Centre National de la Recherche Scientifique

Estación Biológica de Doñana

Universidad Técnica Particular de Loja

Universidad de Alcalá

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Author response for "Uropygial secretion changes mouth colouration in starling nestlings"

Antonio José García‐Núñez Juan José Soler Ester Martínez‐Renau Gustavo Tomás

Starling

10.1098/rsbl.2024.0535/v3/response1

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Citations (0)

Effects of Chemical and Auditory Cues of Hoopoes (Upupa epops) in Repellence and Attraction of Blood-Feeding Flies

Frontiers in Ecology and Evolution (2020)

Gustavo Tomás Carmen Zamora‐Muñoz Manuel Martín‐Vivaldi María Dolores Barón Cristina Ruiz‐Castellano

Research on the mechanisms involved in host location by parasites is of paramount importance and may aid in developing protective measures against them. This topic attains far-reaching repercussions for human and animal welfare regarding parasites transmitting vector-borne pathogens, such as blood-feeding flies. Very few studies have evaluated the effect of bird-derived cues on attraction of vectors in field conditions. We here explored the attraction of different groups of blood-feeding flies (mosquitoes, blackflies and biting midges) to auditory cues produced by begging hoopoe (Upupa epops) nestlings, and to three chemical cues derived from hoopoe nestlings or nests (uropygial secretion, symbiotic bacteria isolated from the secretion, and nest material) in the field. We deployed insect traps baited with the different stimuli at the beginning and at the end of the hoopoe breeding-season in four different habitats. Abundance of blood-feeding flies varied depending on habitat and sampling period. Begging auditory cues of nestling hoopoes did not affect abundance of flies. However, chemical stimuli affected abundance of mosquitoes, which were less abundant in traps baited with bacteria or with nest material than in control traps. Abundance of biting midges in traps also depended on the chemical stimulus but in interaction with sampling period or habitat. Fewer biting midges were collected in traps baited with bacteria and with secretion in the habitats where abundance of biting midges is higher. Our results suggest that uropygial secretion of hoopoes, and symbiotic bacteria living in this secretion, may repel blood-feeding flies from their nests.

Blood meal

Biting

10.3389/fevo.2020.579667

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Citations (13)

MOLECULAR CHARACTERIZATION OF THE 18S rDNA GENE OF AN AVIAN HEPATOZOON REVEALS THAT IT IS CLOSELY RELATED TO LANKESTERELLA

Journal of Parasitology (2006)

Santiago Merino Javier Martı́nez Josué Martínez‐de la Puente A. Criado–Fornelio Gustavo Tomás

As a part of intensive study of blood parasite infections in a population of the passerine bird blue tit (Cyanistes caeruleus, Paridae), we detected a parasite species that, based on its morphological similarity, was tentatively identified as Hepatozoon parus, the only species of this parasite genus described from birds of this family. However, morphological measurements show that H. parus is slightly larger than the parasite detected in our population. A molecular characterization of the parasite species was conducted by amplification of the 18S rDNA gene, using primers that were reported previously to amplify in Hepatozoon sp. of water pythons. Additional primers were developed based on the new sequence obtained. The 1,484-bp fragment amplified reveals that the parasite from our bird population is more closely related to Lankesterella minima than to Hepatozoon species from other vertebrates according to analysis using the BLAST comparison method (93% identity). In addition, phylogenetic analyses using parsimony and Kimura procedures unequivocally related the parasite species detected by PCR with L. minima. The bootstrap values obtained were 97% and 100%, respectively. These results imply that this parasite is a species of a lankesterellid instead of Hepatozoon.

Hepatozoon

10.1645/ge-860r.1

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Citations (36)

A simple trapping method to estimate abundances of blood-sucking flying insects in avian nests

Animal Behaviour (2007)

Gustavo Tomás Santiago Merino Josué Martínez‐de la Puente Juan Moreno Judith Morales

Cyanistes

Ceratopogonidae

Bird nest

10.1016/j.anbehav.2007.08.018

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Citations (51)

Egg colouration predicts brood size, telomere length and body condition of spotless starling fledglings

Journal of Avian Biology (2018)

Juan José Soler Cristina Ruiz‐Castellano Jordi Figuerola Josué Martínez‐de la Puente Magdalena Ruiz‐Rodríguez

Understanding the impressive interspecific variation in avian eggshell colouration has attracted the attention of evolutionary ecologists for more than a century. Several functional explanations predict positive covariation between eggshell pigmentation and phenotypic quality of nestlings. We test this prediction in spotless starlings Sturnus unicolor by using biometric measurements and telomere length of hatchlings and fledglings as proxies of phenotypic quality. Female spotless starlings lay immaculate blue‐green eggs, a sexually selected signal directed to males. Pigmentation predicts positive associations with concentration of antioxidants and testosterone in the yolk and with paternal provisioning effort during nestling growth. Eggshell pigmentation (blue‐green chroma) is not associated with telomere length of hatchlings, which suggests weak maternal effects on this trait. However, we find negative associations of eggshell colouration with both body condition and telomere length of fledglings. Moreover, we find positive associations between eggshell colouration and clutch size, which suggests that sibling competition is higher in nests with more coloured eggshells. Previous works demonstrated that level of sibling competition is positively related to telomere erosion and, thus, the detected negative associations between eggshell colouration, body condition and telomere length of fledglings would reflect higher level of competition in nests with more coloured eggshells. We therefore speculate with the possibility that females that lay larger clutches also lay more coloured eggshells that elicit increased paternal provisioning effort and, thus, raise larger broods at the expense of telomere erosion of their offspring.

Sturnus

Avian clutch size

Hatchling

10.1111/jav.01686

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Citations (11)

Changes in Haemoproteus sex ratios: fertility insurance or differential sex lifespan?

Proceedings of the Royal Society B Biological Sciences (2004)

Santiago Merino Gustavo Tomás Juan Moreno Juan José Sanz Elena Arriero

There is little direct evidence of the fitness effects of changes in malaria gametocyte sex ratio. Gametocyte sex ratios in haemospororin parasites (phylum Apicomplexa) are usually female skewed. However, in some cases and especially in Haemoproteus parasites, less female-biased and even male-biased sex ratios are encountered. The 'fertility insurance hypothesis' tries to explain these biases as an evolutionary strategy to facilitate gamete encounter. Thus, the hypothesis predicts that, if there is a reduction in gametocyte density (intensity of infection) or other factors preventing gametes from meeting, a change to a higher proportion of male gametocytes may be favoured. By contrast, a change in sex ratio may be caused by other non-adaptive mechanisms, for example differential survival of the gametocytes of each sex. We study within-host changes in Haemoproteus majoris sex ratios following an experimental reduction in the density of the parasites in the blood in a breeding population of blue tits (Parus caeruleus). Medication with the antimalarial drug primaquine induced a significant reduction in Haemoproteus gametocyte infection intensity in two different breeding seasons and under two different doses of medication. Sex ratios became male skewed following the experimental treatment in agreement with the predictions of the 'fertility insurance' hypothesis. Also in support of the hypothesis, a significant change towards male-biased sex ratios emerged for non-medicated birds in one year, probably owing to the natural immune reduction of the density of the parasites in the blood. The alternative possibility that changes are caused by different lifespans of gametocytes is not supported by changes in sex ratios in control hosts, where new production and release of gametocytes occur.

Haemoproteus

10.1098/rspb.2004.2764

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Chronic Degradation of Seasonally Dry Tropical Forests Increases the Incidence of Genotoxicity in Birds

GeoHealth (2023)

Gabriela Cevallos-Solorzano Natalia Bailón-Moscoso Leonardo Ordóñez-Delgado Paul Jara Gustavo Tomás

Abstract Multiple studies have shown that exposure to pollutants can increase genotoxic damage in different taxa. However, to our knowledge, the effects of environmental stress have been explored little. In certain stressful ecosystems, such as seasonally dry tropical forests, the combined effects of anthropogenic activities and ongoing global changes can cause an increase in environmental stresses, in turn, may trigger physiological and genetic effects on biodiversity. The present aims to assess changes in the prevalence of genotoxic damage in birds within three states of forest degradation in the Tumbesian Region of Western Ecuador. We used blood samples from 50 bird species to determine the frequency of micronucleus and nuclear abnormalities in erythrocytes. Our results revealed a significant impact of forest degradation on the occurrence probability of micronucleus and nuclear abnormalities at the community level. Localities with higher levels of degradation exhibited higher levels of abnormalities. However, when analyzing the dominant species, we found contrasting responses. While Lepidocolaptes souleyetii showed a reduction in the proportion of nuclear abnormalities from the natural to shrub‐dominated localities Troglodytes aedon and Polioptila plumbea showed an increase for semi‐natural and shrub‐dominated respectively. We concluded that the degradation process of these tropical forests increases the stress of bird community generating genotoxic damage. Bird responses seem to be species‐specific, which could explain the differences in changes in bird composition reported in other studies.

Troglodytes

10.1029/2022gh000774

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Nest Construction Rate and Stress in Female Pied FlycatchersFicedula hypoleuca

Acta Ornithologica (2008)

Juan Moreno Javier Martı́nez Consuelo Corral Elisa Lobato Santiago Merino

Nest building effort has received scant attention in the literature although it may involve costs which can be detected as physiological stress. We prolonged nest construction effort in a population of Spanish Pied Flycatchers by removing nests from nest-boxes and forcing females to build a second nest. In comparison with control nests, the experimental females had to work for longer periods and accumulate more nest material, but nest construction rates (g of nest material per day of construction) were not affected. There was a positive association of clutch mass with nest construction rate. To measure physiological stress, we captured females shortly after laying to obtain blood samples for heat-shock protein quantification. Heat-shock proteins quantify stress at cell level. The level of HSP60 in peripheral blood was positively associated with total nest construction rate (including second nests for experimental females), but not with laying date, clutch mass or experimental treatment. A third of the variation in the HSP60 level was explained by the nest construction rate. Fast nest builders are physiologically stressed, suggesting that the nest construction rate may constitute an index of female physiological performance.

Ficedula

Nest box

Avian clutch size

10.3161/000164508x345338

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Citations (58)

Nest Weight and Female Health in the Blue Tit (Cyanistes Caeruleus)

Ornithology (2006)

Gustavo Tomás Santiago Merino Juan Moreno Juan José Sanz Judith Morales

Abstract We explored two hypotheses that may explain intraspecific variability in nest size. The “thermoregulatory” hypothesis states that species adjust nest size to maintain egg temperature and minimize temperature fluctuations in the nest. Recently, the suggestion has been made that nest size may reflect the health status or phenotypic quality of the builder, potentially making it a sexually selected trait (“sexual selection” hypothesis). For two years, we weighed nests of Blue Tit (Cyanistes caeruleus) at initiation of reproduction in a nest-box breeding population in central Spain. We recorded laying date, clutch size, incubation period, and hatching success. We measured and took blood samples of adult females when nestlings reached three days of age. General regression models controlling for potential variables that could affect nest weight revealed that prevalence of Trypanosoma avium and immunoglobulin levels in females were significantly related to nest weight in only one of the study years. Females not infected with Trypanosoma avium built heavier nests than infected ones, whereas female immunoglobulin levels were negatively associated with nest weight. Hatching success and duration of the incubation period were not related to nest weight in either year. Thus, our results do not support the thermoregulatory hypothesis and show that certain measures of female health are related to nest-building effort in some years, probably depending on environmental conditions. Peso del Nido y Estado de Salud de la Hembra en el Cyanistes caeruleus

Cyanistes

Avian clutch size

10.1093/auk/123.4.1013

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Citations (20)

MHC‐I provides both quantitative resistance and susceptibility to blood parasites in blue tits in the wild

Journal of Avian Biology (2016)

Juan Rivero de Aguilar Helena Westerdahl Josué Martínez‐de la Puente Gustavo Tomás Javier Martı́nez

Major histocompatibility complex (MHC) genes are central for the adaptive immune response against parasites. Here, we investigated potential associations among MHC‐I alleles and blood parasite infections in a natural breeding population of a passerine bird, the blue tit Cyanistes caeruleu s, in central Spain. We screened both infection status (presence/absence of infection) and infection intensity to the pathogenic blood parasites Haemoproteus and Leucocytozoon . Three MHC‐I alleles (UA104, UA108 and UA117) were associated with higher or lower infection intensities by Leucocytozoon . Interestingly, these associations were dependent on age and were found both among young and adult birds. No MHC alleles were associated with infection intensity by Haemoproteus parasites. In addition, no significant relationships were detected between infection status by Haemoproteus and Leucocytozoon infections and MHC alleles. The very high prevalence of these two parasites in our study population (79–100%) poses challenges to identify associations with infection status and also suggests that clearance of infections may be rare. In conclusion, associations between specific MHC‐I alleles and Leucocytozoon parasites were related to either high or low infection intensities, and hence increased susceptibility or resistance to infection.

Haemoproteus

Leucocytozoon

Cyanistes

10.1111/jav.00830

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Citations (24)