Lichens in the nests of European starling Sturnus vulgaris serve a mate attraction rather than insecticidal function

The European starling Sturnus vulgaris is a hole-nesting bird in which the male builds a voluminous nest using a wide variety of materials such as twigs, grass, leaves, feathers, and lichens. The function of lichens in starling nests has not been assessed until now and we hypothesize that this material is related to a mate attraction function or is used to protect nestlings from parasites due to the presence of secondary compounds with insecticidal effects with the lichens. We aimed to identify the lichen species and frequency of lichen use in European starling nests, and to determine if the presence of this material is correlated with mate attraction or with an insecticidal function. We found lichens in 45% of nests, mainly represented by Ramalina celastri. The lichens were added to the nests mainly before the beginning and at the end of nest building and egg-laying started earlier in nests with lichens than those without lichens. No association was found between the presence of lichen and the intensity of Philornis larvae (Diptera), a parasite that infests starling nestlings. Our results suggest that the addition of lichens could be related to mate attraction and a stimulus for the beginning of egg-laying but did not have an antiparasitic function in European starling nests.Fil: Ibañez, Lucía Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico Zoología Vertebrados; ArgentinaFil: García, Renato Andrés. Laboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fiorini, Vanina Dafne. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Montalti, Diego. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico Zoología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Preferential Begging Responses of Shiny Cowbirds to the Conspecific Chatter Call

Avian brood parasites lay their eggs into the nests of other species, which incubate them and raise the chicks until their independence. Despite living their early weeks of life surrounded by heterospecifics, young brood parasites have the ability to recognize and associate to conspecifics after independence. It has been proposed that the initial conspecific recognition develops when a young parasite encounters a unique species-specific signal that triggers the learning of other aspects of the producer of the signal. For cowbirds (Molothrus spp.), this species-specific signal is hypothesized to be the chatter call. Young birds also could express auditory biases, which in some cases lead to discrimination in favor of conspecific songs. Therefore, the perceptual selectivity for chatters might be also present in nestlings. Our aim was to assess if nestlings of the shiny cowbird (M. bonariensis) present a preferential begging response to conspecific chatter calls. We evaluated if they respond more to the parasitic vocalization than host chicks and if they respond more to the chatter than to heterospecific nonhost calls. We tested shiny cowbird chicks reared by chalk-browed mockingbirds (Mimus saturninus) or house wrens (Troglodytes aedon) and host chicks, as control species. We randomly presented to 6-day-old chicks the following playback treatments: (1) conspecific chatter calls, (2) host calls, used as positive controls, and (3) nonhost calls, used as negative control. We measured if chicks begged during the playback treatments and the begging intensity. When responding to the playback of chatter calls, shiny cowbird chicks begged at a higher frequency and more intensively than host chicks. Shiny cowbird chicks reared by mockingbirds begged more intensively to playbacks of conspecific chatter calls than to host calls, while those reared by wrens begged with a similar intensity to playbacks of conspecific chatter and host calls. On the contrary, wren nestlings begged more intensively to playbacks of the wren call than to chatter calls. Mockingbird nestlings did not beg during any treatment. None of the three species begged during the playback of nonhost calls. Our results show that the chatter call produced a preferential begging response in cowbird nestlings, which may be the beginning of a process of conspecific recognition.Fil: Crudele, Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Reboreda, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Fiorini, Vanina Dafne. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentin

Coproparasitological study of European starling nestlings (Sturnus vulgaris) in Argentina

We examined 71 fecal samples of European starling nestlings from Buenos Aires Province, Argentina, in the reproductive seasons of 2012 and 2013 to detect the presence of intestinal parasites and determine their prevalence. Total parasite prevalence was 26.8%. We found one coccidial species (Isospora sp.) with a prevalence of 25.35% and one cestode species with a prevalence of 1.4%. These values are lower than those reported for starlings from Europe and North America. Our results suggest that a reduction in the diversity of parasite species was likely to have occurred during the introduction process of this bird in Argentina, thus contributing to its invasive success.Facultad de Ciencias Naturales y Muse

Parasitism by Botflies Philornis Sp. on European Starlings Sturnus vulgaris, an Exotic Bird in Argentina

Fil: Ibáñez, Lucía Mariel. División Zoología Invertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Fiorini, Vanina Dafne. Departamento de Ecología, Genética y Evolución. Instituto IEGEBA (CONICET-UBA). Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires; ArgentinaFil: Montalti, Diego. División Zoología Vertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Di Iorio, Osvaldo. Departamento de Biodiversidad y Biología Experimental. Instituto IBBEA (CONICET-UBA). Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires; ArgentinaFil: Turienzo, Paola. Departamento de Biodiversidad y Biología Experimental. Instituto IBBEA (CONICET-UBA). Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires; Argentin

A comparative study of the structural and mechanical properties of avian eggshells among hosts of obligate brood parasitic cowbirds (genus Molothrus)

Obligate avian brood parasites depend on hosts for parental care, which in turn suffer fitness losses as a result of parasitism. Mechanisms by which brood parasitic cowbirds (Molothrus spp.) reduce host breeding success include the puncture (M. rufoaxillaris and M. bonariensis) or removal (M. ater) of the eggs of the host. Our working hypothesis is that the host eggs' mechanical strength and their size and shape in species with higher frequency of parasitism covaries with the cowbird's strategy to reduce host clutch size. Our results, obtained through phylogenetic analyses based on egg 2D geometric morphometry and eggshell mechanical and ultrastructural measurements, suggest that egg-puncturer behaviour has led to an increase in the strength of the host's eggshell, which might make them more difficult to be pierced. We also characterized larger, more rounded and asymmetrical eggs in frequent hosts of M. ater, which might be more difficult to be removed. These interspecific host egg and shell traits were also positively affected by the frequency of parasitism, indicating that species-specific patterns of parasitic costs select for respective anti-parasitic defences in hosts.Fil: Lopez, Analia Veronica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Reboreda, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Fiorini, Vanina Dafne. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Gerschenson, Lia Noemi. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hauber, Mark E.. University of Illinois. Urbana - Champaign; Estados Unido

Coproparasitological study of European starling nestlings (Sturnus vulgaris) in Argentina

We examined 71 fecal samples of European starling nestlings from Buenos Aires Province, Argentina, in the reproductive seasons of 2012 and 2013 to detect the presence of intestinal parasites and determine their prevalence. Total parasite prevalence was 26.8%. We found one coccidial species (Isospora sp.) with a prevalence of 25.35% and one cestode species with a prevalence of 1.4%. These values are lower than those reported for starlings from Europe and North America. Our results suggest that a reduction in the diversity of parasite species was likely to have occurred during the introduction process of this bird in Argentina, thus contributing to its invasive success.Facultad de Ciencias Naturales y Muse

Parasitismo de estorninos pintos Sturnus vulgaris, un ave exótica en Argentina, por moscardones Philornis sp.

We studied the parasitism of the exotic European starling Sturnus vulgaris by native botflies Philornis spp. in Argentina. We installed thirty nest boxes in the northeastern Buenos Aires province in the 2010–2011 breeding season. In the first brood, subcutaneous larvae of Philornis (Muscidae) parasitised 34 nestlings (89.4%) of 11 clutches (91.6%) and only three nestlings fledged. In the second brood, Philornis parasitised 15 (48.3%) nestlings of seven clutches (70%) and all the nestlings died. Compared to the mortality of other Neotropical birds parasitised by Philornis, the mortality in European starling nests is the highest found in the region. Our results show that the studied population of European starling suffers a high level of parasitism by Philornis, although this factor was not directly associated with the high mortality of starling nestlings. The fact that most non-parasitised nestlings also died indicates that other factors are also affecting nestling survival. Experiments that allow us to isolate the effect of Philornis from other variables would be needed to evaluate the impact of botfly larvae on starling nestlings.Estudiamos el parasitismo de una especie de mosca nativa del género Philornis sobre el estornino pinto Sturnus vulgaris en Argentina, que es un ave introducida recientemente en este país. Utilizamos 30 cajas-nido en el noreste de la provincia de Buenos Aires en el período de reproducción 2010-2011. En la primera nidada fueron parasitados 34 pollos (89,4%) de 11 nidos (91,6%) por larvas subcutáneas de Philornis (Muscidae) y sólo tres pollos sobrevivieron. En la segunda nidada fueron parasitados por Philornis 15 pollos (48,3%) de 7 nidos (70%) y todos murieron. Si comparamos la mortalidad de otras aves neotropicales parasitadas por Philornis, la mortalidad de los pollos de estornino pinto es la mayor encontrada en la región. Nuestros resultados muestran que la población de estornino pinto estudiada sufre un alto nivel de parasitismo por Philornis pero este factor no estuvo directamente asociado a la alta mortalidad de pollos de estornino. El hecho de que la mayoría de los pollos parasitados y no parasitados murieran indica que otros factores están afectando la supervivencia de los pollos. Serían necesarios experimentos que permitan aislar el efecto de Philornis del resto de las variables para poder evaluar el impacto de las larvas sobre los pollos de estornino.Facultad de Ciencias Naturales y Muse

El Estornino Pinto (Sturnus vulgaris): estimación de la densidad poblacional e interacciones con especies nativas en parques urbanos de Buenos Aires

The European Starling (Sturnus vulgaris) was introduced in Argentina by 1987. Starlings aresecondary cavity nesters and may constitute a threat to other cavity nesters. We estimated the density of starlings in Buenos Aires city urban parks and examined the relationships between some habitat characteristics and the presence and abundance of starlings. We also evaluated the interactions between starlings and native species, by observations during foraging and nesting. Because starlings may use Rufous Hornero (Furnarius rufus) dome-shaped nests, we also located and observed them. Starlings were recorded in 293 transects distributed in 20.8 km2 corresponding to 103 Buenos Aires public-access parks, in which 447 individuals were recorded. We found that the relative population density for starlings in parks of Buenos Aires (individuals/ha ± SD) was 2.21 ± 0.09. Starling presence was positively associated with the park area and number of palms and negatively with the number of trees. A positive significant association between starling density and number of tipu trees was also found. Neither the presence nor the abundance of starlings was associated with the park’s avian species richness. Although starlings were found to feed in heterospecific flocks in 60.3% of the 58 observations (totally 464 min), only five interspecific interactions were recorded (the starling being always the losing species). Twenty-one starling nests were built in natural cavities and nine in cavities made by woodpeckers (Colaptes spp.). None of the 26 Rufous Hornero nests found was occupied by starlings. However, the nestling cycle of the Golden-breasted Woodpecker (Colaptes melanolaimus) was recorded to be interrupted in three occasions due either to aggressive interactions or to the presence of starlings near the nests. These findings can be relevant in relation with the need of any action against starlings in Argentina.Fil: Rebolo, Natalia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Fiorini, Vanina Dafne. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentin

Imprinting in an interspecific brood parasitic bird

Many animals learn to recognize conspecifics after an early experience with them through sexual imprinting. For brood parasitic birds, it is not possible to develop conspecific recognition using cues provided by their foster parents. One solution is that a unique species-specific signal triggers the learning of additional aspects of the conspecific's phenotype. It has been proposed that for brood parasitic cowbirds, this signal is an innate vocalization, the chatter. This vocalization might act in a cross-modal learning process through which juveniles that listen to the song learn to recognize the visual characteristics of the song's producer. We trained two groups of juvenile shiny cowbirds (Molothrus bonariensis). In one group, individuals listened to the chatter or a heterospecific call while they observed a stuffed model of the corresponding species. In the other group, individuals listened to the call of one species (cowbird or heterospecific) while they observed the stuffed model of the other species. In the preference test, juveniles chose the model associated with the chatter, regardless of whether the model was a cowbird or a heterospecific. These results show how the auditory system through a species-specific signal can lead to cross-modal learning of visual cues allowing conspecific recognition in brood parasitic cowbirds.Fil: Crudele, Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Reboreda, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Fiorini, Vanina Dafne. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentin