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Reproductive effort reduces long-term immune function in breeding tree swallows (Tachycineta bicolor).

Ardia, Daniel R; Schat, Karel A; Winkler, David W
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 22/08/2003 Português
Relevância na Pesquisa
46.98%
We examined whether strategies of reproductive allocation may reduce long-term immunocompetence through the effects of manipulated effort on secondary or acquired immunity. We tested whether increased reproductive effort leads to reduced immune function and survival by manipulating brood size in tree swallows (Tachycineta bicolor) and exposing breeding females to a primary and secondary exposure of sheep red blood cells to elicit a humoral immune response. Females raising enlarged broods produced fewer secondary antibodies than did females raising control or reduced broods. Most importantly, individuals with high secondary responses were more likely to survive to breed 3 years after brood manipulations, suggesting that differences in disease susceptibility may be caused by trade-offs in reproductive allocation. We also found that individual quality, measured by clutch initiation date, mediated the effects of brood manipulations, with higher-quality birds showing a greater ability to deal with increases in effort.

Experimental heating reveals nest temperature affects nestling condition in tree swallows (Tachycineta bicolor)

Pérez, Jonathan H; Ardia, Daniel R; Chad, Elise K; Clotfelter, Ethan D
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.98%
Investment in one life-history stage can have delayed effects on subsequent life-history stages within a single reproductive bout. We experimentally heated tree swallow (Tachycineta bicolor) nests during incubation to test for effects on parental and nestling conditions. Females incubating in heated boxes maintained higher body condition and fed nestlings at higher rates. We cross-fostered nestlings and found that young nestlings (4–7 days old) incubated in heated nests had higher body condition and body mass, regardless of treatment status of their rearing parent. However, older nestlings which were fed by heated females maintained higher condition and body mass regardless of treatment status of their incubating parent. These results indicate that investment in one life-history stage can have multiple pathways of carry-over effects on future life-history stages.

Temperature effects on food supply and chick mortality in tree swallows (Tachycineta bicolor)

Winkler, David W.; Luo, Miles K.; Rakhimberdiev, Eldar
Fonte: Springer Berlin Heidelberg Publicador: Springer Berlin Heidelberg
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.98%
Tree swallow (Tachycineta bicolor) breeding success in Ithaca, NY, USA, over the past quarter century has shown generally healthy fledgling production punctuated by years of high nestling mortality. This study tested the potential effects that temperature may have on the food supply and breeding success of swallows. Data from 17 years of daily insect samples were used to relate flying insect abundances to daily maximum temperatures and to define “cold snaps” as strings of consecutive days when the maximum temperatures did not exceed critical temperatures. The distributions of cold snaps and chick mortality events were investigated both through detailed reconstructions of the fates and fate dates of individual chicks, focused on the three breeding seasons of lowest fledging success, and with less detailed brood-level analyses of a larger 11-year dataset including years of more moderate mortality. Mark–recapture analyses of daily brood survival rate (DSR) reveal very strong support for the effects of cold temperatures on brood survival rates, and all the top models agree on a critical temperature of 18.5 °C for insect flight activity in Ithaca. The individual-level analyses, focused on years of higher mortality, favored a 3-day cold snap definition as the most predictive of DSR effects...

Offspring sex ratios in relation to maternal condition, paternal attractiveness and extrapair paternity in the tree swallow (Tachycineta bicolor)

Delmore, Kira
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 270580 bytes; application/pdf
Português
Relevância na Pesquisa
46.98%
When the reproductive value of sons and daughters differ, parents should adjust the sex ratio of their offspring to produce more of the sex that provides greater fitness returns. Parental genetic effects like body condition may influence these fitness returns. The purpose of this thesis was to investigate population and family level patterns of sex allocation in the tree swallow (Tachycineta bicolor). In a previous tree swallow study, females produced more sons in their broods when they were in better body condition. I evaluated this relationship on a different population of tree swallows. I also investigated the predictions that (1) females mated to attractive males should bias the sex ratio of their offspring in favour of sons and (2) females should adjust the sex ratio of extrapair offspring in favour of sons. The sex of 464 offspring in 91 broods was determined using molecular sex techniques. The overall offspring sex ratio did not deviate significantly from 1:1. Within broods, male-biased sex ratios were associated with females in better condition, confirming the pattern of sex allocation found in the previous tree swallow study and suggesting that this pattern of sex ratio manipulation is repeatable in this bird species. Male-biased brood sex ratios were not associated with females mated to attractive males. This finding could suggest that variance in these traits is not great enough to produce observable trends or that traits measured are not used by females to assess the quality of their mate. Extrapair offspring within broods with mixed paternity were equally likely to be male or female. The selective pressure on females to bias the sex ratio of extrapair offspring in favour of males may not be sufficient in our population of tree swallows to cause detectable patterns in sex allocation among extrapair offspring.

Hormones and offspring sex ratio bias: do parental corticosteroid levels correlate with offspring sex ratio in tree swallows (Tachycineta bicolor)?

Munro, Hannah
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 421524 bytes; application/pdf
Português
Relevância na Pesquisa
46.98%
Offspring sex ratio biasing has been documented in many avian species, including tree swallows (Tachycineta bicolor). While occurrence of sex ratio biasing is well documented, the mechanisms underlying this phenomenon remain unknown. Previous studies have suggested a causal relationship between corticosteroids (cort) and sex ratio biasing. I looked at the relationship between offspring sex ratio and parental baseline cort levels in a box-nesting population of tree swallows at Queen’s University Biological Station in Ontario, Canada. I measured both male and female cort levels and analyzed their relationships to sex ratio of their offspring. I did not find a significant relationship between maternal or paternal cort levels measured at any time throughout the breeding season and offspring sex ratio. I found that maternal cort varied within individuals across the breeding season. These findings suggest that a relationship between sex ratio biasing and cort might not exist, or such a relationship exists, but is not detectable at all points in time (e.g., all years or all breeding stages). Based on the results of previous correlative and experimental studies finding a link between cort and sex ratio in other birds, and the high level of within-individual variation found in female tree swallow cort levels...

Body Condition Matters: The Effects of Resource Availability on Resource Allocation Patterns in Tree Swallows (Tachycineta bicolor)

Lockhart, Laura
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 482759 bytes; application/pdf
Português
Relevância na Pesquisa
46.98%
Within-individual trade-offs in resource allocation exist because of constraints and limitations on those resources. Because of these constraints and limitations, an individual may have to apportion investment differentially to, for example, immune system function, reproductive function, and response to environmental challenges. Despite its relevance in ecology, we do not know how all of these functions are linked, and particularly how resources are allocated in organisms confronted with environmental challenges. I test whether individuals of differing body conditions exhibit different resource allocation patterns when faced with endoparasites. I examined the relationships between blood parasitemia levels in a free-ranging population of tree swallows (Tachycineta bicolor) with high and low stored resource availability (body condition) and measures of their immune and reproductive investment. I found trends (p < 0.13) for a positive relationship between reproductive investment and immune investment and between reproductive investment and parasitemia in high body condition females. I also found a trend (p < 0.17) for a negative relationship between parasitemia and immune function in low body condition females and a negative relationship (p < 0.03) between immune and reproductive investment in low body condition males. My findings imply different resource allocation strategies that occur in individuals of varying sex and body conditions under stressful conditions. Further study is needed to determine the causality of these correlative relationships and the physiological mechanisms that mediate them.; NSERC

Correlates of breeding adult survival in the box nesting population of Tree Swallows (Tachycineta bicolor) at the Queen’s University Biological Station

Willis, Tristan
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
67.26%
In migratory birds, intensive data collection on the breeding ground contrasts with relatively little study during the remainder of the annual cycle. Few studies have used information from the breeding ground to look for correlates with inter-annual survival in long term data sets. I use a 27-year data set from the box nesting population of Tree Swallows (Tachycineta bicolor) at the Queen’s University Biological Station to test the hypothesis that reproductive output, body condition, and timing of breeding influence probability of survival in individual Tree Swallows. I also examine the potential influences of age in females and plumage colouration in one-year-old females. Birds that fledged more offspring had higher survival rates than birds with lower reproductive output. Body condition was an important variable in improving model fit, but was not directly correlated with survival. Older females survived at a higher rate than one-year-old females. Timing of breeding was not correlated with probability of survival in adult Tree Swallows, nor was plumage colouration in one-year-old females. This study is unique in providing one of the first large-scale, multivariate assessments of factors influencing survival in a migratory bird species.; J. Allen Keast Lake Opinicon Undergraduate Research Fellowship...

Do glucocorticoids mediate resource allocation in breeding tree swallows (Tachycineta bicolor)?

Dobson, Emily
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
67.26%
All individuals allocate limited resources towards self-maintenance (meeting energy requirements for growth and development) and reproduction (producing and rearing offspring). Different physiological systems of the body attempt to balance these processes in order to maximize lifetime reproductive success. The precise mechanisms underlying adaptive allocation towards competing life history traits are unknown. One possible mechanism of mediating resource allocation is through the release of glucocorticoid (GC) hormones. Corticosterone (cort) is the primary GC found in birds, reptiles and amphibians and a good candidate for mediating shifts in resource allocation because (1) challenges that result in reduced energy availability, such as food limitation or disease, induce increased secretion of baseline cort, and (2) cort secretion can result in mobilization of energy stores. To investigate the effects of cort on resource allocation, we conducted two complementary studies in tree swallows (Tachycineta bicolor). First, we compared birds that received cort-implants with birds that received control-implants and un-implanted controls to identify causal effects of increased cort on resource allocation. We found no significant effect of implant type on measures of reproductive effort...

Baseline glucocorticoids predict variation in nest defense in tree swallows (Tachycineta bicolor)

Burns, Sara
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
46.98%
An incredible amount of variation exists in parental quality and behaviour among individuals, populations, and species. Variation in behaviour has been partially explained by physiological differences within individuals, including various aspects of the endocrine system. The endocrine response to stress might contribute to such variation in behaviour, but we lack evidence from natural, free-ranging populations. We sought to predict parental behaviour in a widely studied avian species, the tree swallow (Tachycineta bicolor), investigating the relationship between variation in baseline glucocorticoid (cort) hormone levels and nest defense behaviour. Using presentation of a model gray ratsnake (Pantherophis spiloides), a predator of nestlings in this population, we quantified nest defense behaviour in order to test to the following hypotheses: (1) The Increased Fitness Hypothesis: baseline cort increases with increased energetic demand and reproductive investment, and this is reflected in parental behaviour, and (2) The Personality Hypothesis: baseline cort and nest defense are associated with personality, where lower baseline cort levels have been found to generally be associated with increased aggression and boldness. More reactive and bold individuals had higher baseline cort levels...

When should individuals take risks? Identifying predictors of neophobia in tree swallows (Tachycineta bicolor)

Domalik, Alice
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
67.26%
Understanding the underlying causes of individual variation in risk-taking behaviour has been a growing area of research in recent years, and evidence suggests that personality, reproductive effort, age, and individual quality can all influence this behaviour. Here, I aimed to identify which of these factors are important predictors of risk-taking in breeding tree swallows (Tachycineta bicolor) by measuring their response to a novel object (neophobia – fear of the new). I used corticosterone, a glucocorticoid hormone involved in energy allocation and metabolism, to test whether neophobia was predicted by reproductive investment or personality. Baseline corticosterone has been shown to increase in conjunction with reproductive effort. However, baseline corticosterone has also been found to correlate with personality, with bolder individuals having lower levels. Therefore, I predicted to find one of two relationships: if neophobia is related to reproductive investment, I predicted that neophobia would decrease with increasing baseline corticosterone. However, if neophobia is related to personality, I predicted that baseline corticosterone would increase with neophobia. In females, I did not find support for either hypothesis, although inclement weather could have influenced these findings. However in males...

Variation in nest defense behavior within and among individual Tree Swallows (Tachycineta bicolor)

St John, Prianka
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
46.98%
The degree of parental behavior varies not only between species, but also among populations and individuals within species. The causes of variation in parental behavior within species are not fully understood. Additionally, relatively few studies have attempted to quantify within individual variation in parental behavior. Here, we used repeated presentation of a model of a nest predator, Black Ratsnake (Pantherophis obsoletus), to individual Tree Swallows (Tachycineta bicolor), to quantify among and within individual variation in nest defense. We tested the following non-mutually exclusive hypotheses, 1) The ‘Parental Investment hypothesis’: nest defense varies among individuals due to varying individual levels of parental investment, and 2) The ‘Repeatability hypothesis’: nest defense represents a consistent behavioral strategy within individuals. We assessed the relationships between intensity of nest defense behavior and measures of body condition and reproductive investment. We also measured the repeatability of nest defense behavior within individuals between two behavioral trials, within the period of care of offspring. Several of our findings support the ‘Parental Investment hypothesis’; parents with greater levels of reproductive investment defended nests more intensely. For instance...

Analysis of the Optimal Duration of Behavioral Observations Based on an Automated Continuous Monitoring System in Tree Swallows (Tachycineta bicolor): Is One Hour Good Enough?

Lendvai, Ádám Z.; Akçay, Çağlar; Ouyang, Jenny Q.; Dakin, Roslyn; Domalik, Alice D.; St John, Prianka S.; Stanback, Mark; Moore, Ignacio T.; Bonier, Frances
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 11/11/2015 Português
Relevância na Pesquisa
46.98%
Studies of animal behavior often rely on human observation, which introduces a number of limitations on sampling. Recent developments in automated logging of behaviors make it possible to circumvent some of these problems. Once verified for efficacy and accuracy, these automated systems can be used to determine optimal sampling regimes for behavioral studies. Here, we used a radio-frequency identification (RFID) system to quantify parental effort in a bi-parental songbird species: the tree swallow (Tachycineta bicolor). We found that the accuracy of the RFID monitoring system was similar to that of video-recorded behavioral observations for quantifying parental visits. Using RFID monitoring, we also quantified the optimum duration of sampling periods for male and female parental effort by looking at the relationship between nest visit rates estimated from sampling periods with different durations and the total visit numbers for the day. The optimum sampling duration (the shortest observation time that explained the most variation in total daily visits per unit time) was 1h for both sexes. These results show that RFID and other automated technologies can be used to quantify behavior when human observation is constrained, and the information from these monitoring technologies can be useful for evaluating the efficacy of human observation methods.

Variables que afectan el peso de los huevos en la Golondrina Ceja Blanca (Tachycineta leucorrhoa).; Variable affecting egg mass of white-rumped swallow (Tachicyneta leucorrhoa).

Barrionuevo, Melina; Bulit, Florencia; Massoni, Viviana
Fonte: Aves Argentinas / Asociación Ornitológica del Plata Publicador: Aves Argentinas / Asociación Ornitológica del Plata
Tipo: info:eu-repo/semantics/article; artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em 30/03/2010 Português
Relevância na Pesquisa
47.52%
Los recursos que asignan las hembras a sus huevos pueden tener importantes consecuencias en la vida de los pichones. La condición física de las hembras, la abundancia de alimento, las condiciones ambientales, la cantidad de huevos por puesta y la fecha de puesta son variables que suelen afectar el tamaño de los huevos en aves passeriformes. En este trabajo se estudió el efecto de estas variables sobre el peso de los huevos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa). La abundancia de insectos aéreos se estimó usando trampas cono y trampas de acrílico. El peso de los huevos fue mayor para las hembras de mejor condición física y cuanto mayor fue la temperatura promedio durante los días previos a la puesta. Estos resultados concuerdan con los obtenidos para la Golondrina Bicolor (Tachycineta bicolor), un congénere del Hemisferio Norte.; Resource allocation by female birds into their eggs may have important consequences on nestlings’ life. Female’s body condition, food abundance, environmental conditions, clutch size and lay date are some of the variables described to affect egg mass in Passeriformes. We studied the effect of those variables on egg mass of White-rumped Swallow (Tachycineta leucorrhoa). Aerial insect abundance was estimated using cone and acrylic traps. Egg mass was positively related to female body condition and to mean ambient temperatures during egg formation. These results are in agreement with those found for Tree Swallow (Tachycineta bicolor)...

Arquitectura de los nidos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa) construidos en cajas nido; Architecture of white-rumped swallow’s (Tachycineta leucorrhoa) nests built in nest boxes

Bulit, Florencia; Massoni, Viviana
Fonte: Aves Argentinas / Asociación Ornitológica del Plata Publicador: Aves Argentinas / Asociación Ornitológica del Plata
Tipo: info:eu-repo/semantics/article; artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em /12/2004 Português
Relevância na Pesquisa
47.55%
La arquitectura de los nidos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa) no ha sido descripta en detalle hasta el momento y posiblemente varíe con las dimensiones de la cavidad en la cual son construidos. Se describen las etapas de la construcción, la arquitectura y los elementos que componen los nidos de esta especie en cajas nido de iguales dimensiones. Las golondrinas ocuparon el 25% de la altura de la caja y construyeron la copa en el centro del espacio disponible (donde el aislamiento térmico de la temperatura externa es mayor) y nunca cerca de la entrada (donde el riesgo de predación es mayor). A medida que avanzó la temporada reproductiva, las golondrinas redujeron el tiempo de construcción de la base, iniciaron la puesta de los huevos con un número menor de plumas acolchando la copa y terminaron el nido más rápidamente; el número final de plumas en la copa y corona, sin embargo, fue mayor. No se encontró relación entre el éxito de los nidos y el avance de la temporada reproductiva o la composición de los nidos. Se compararon estos nidos con los que construye la Golondrina Bicolor (Tachycineta bicolor) en el Hemisferio Norte.; The architecture of White-rumped Swallow´s (Tachycineta leucorrhoa) nests has not been described yet...

Roosts and migrations of swallows; Dormideros y migraciones de golondrinas

Winkler, David W.
Fonte: Aves Argentinas / Asociación Ornitológica del Plata Publicador: Aves Argentinas / Asociación Ornitológica del Plata
Tipo: info:eu-repo/semantics/article; artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em /12/2006 Português
Relevância na Pesquisa
27.09%
Swallows of the north temperate zone display a wide variety of territorial behaviour during the breeding season, but as soon as breeding is over, they all appear to adopt a pattern of independent diurnal foraging interleaved with aggregation every night in dense roosts. Swallows generally migrate during the day, feeding on the wing. On many stretches of their annual journeys, their migrations can thus be seen as the simple spatial translation of nocturnal roost sites with foraging routes straightening out to connect them. However, swallows that must make long journeys over ecological barriers clearly fly at night as well as in the day, and many suggestions indicate that there is considerable complexity in the altitude and bearing of flights even during the day. There are especially intriguing indications that much swallow migration may take place high out of sight of ground observers with movements near the ground often associated with foraging in passage. Provided that roost sites can be reliably found, swallow migration can be extremely flexible, and there are interesting contrasts in the biogeography and phenological flexibility of swallows compared to other passerine birds. Even within the swallows, there is considerable interspecific and intraspecifc variability in the distances of their annual migrations...

Variables que afectan el peso de los huevos en la Golondrina Ceja Blanca (Tachycineta leucorrhoa).; Variable affecting egg mass of white-rumped swallow (Tachicyneta leucorrhoa).

Barrionuevo, Melina; Bulit, Florencia; Massoni, Viviana
Fonte: Revista de Ornitología Neotropical; Aves Argentinas; Aves Argentinas / Asociación Ornitológica del Plata Publicador: Revista de Ornitología Neotropical; Aves Argentinas; Aves Argentinas / Asociación Ornitológica del Plata
Tipo: info:eu-repo/semantics/article; artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em 30/03/2010 Português
Relevância na Pesquisa
47.52%
Los recursos que asignan las hembras a sus huevos pueden tener importantes consecuencias en la vida de los pichones. La condición física de las hembras, la abundancia de alimento, las condiciones ambientales, la cantidad de huevos por puesta y la fecha de puesta son variables que suelen afectar el tamaño de los huevos en aves passeriformes. En este trabajo se estudió el efecto de estas variables sobre el peso de los huevos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa). La abundancia de insectos aéreos se estimó usando trampas cono y trampas de acrílico. El peso de los huevos fue mayor para las hembras de mejor condición física y cuanto mayor fue la temperatura promedio durante los días previos a la puesta. Estos resultados concuerdan con los obtenidos para la Golondrina Bicolor (Tachycineta bicolor), un congénere del Hemisferio Norte.; Resource allocation by female birds into their eggs may have important consequences on nestlings’ life. Female’s body condition, food abundance, environmental conditions, clutch size and lay date are some of the variables described to affect egg mass in Passeriformes. We studied the effect of those variables on egg mass of White-rumped Swallow (Tachycineta leucorrhoa). Aerial insect abundance was estimated using cone and acrylic traps. Egg mass was positively related to female body condition and to mean ambient temperatures during egg formation. These results are in agreement with those found for Tree Swallow (Tachycineta bicolor)...

Roosts and migrations of swallows; Dormideros y migraciones de golondrinas

Winkler, David W.
Fonte: Revista de Ornitología Neotropical; Aves Argentinas; Aves Argentinas / Asociación Ornitológica del Plata Publicador: Revista de Ornitología Neotropical; Aves Argentinas; Aves Argentinas / Asociación Ornitológica del Plata
Tipo: info:eu-repo/semantics/article; artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em /12/2006 Português
Relevância na Pesquisa
27.09%
Swallows of the north temperate zone display a wide variety of territorial behaviour during the breeding season, but as soon as breeding is over, they all appear to adopt a pattern of independent diurnal foraging interleaved with aggregation every night in dense roosts. Swallows generally migrate during the day, feeding on the wing. On many stretches of their annual journeys, their migrations can thus be seen as the simple spatial translation of nocturnal roost sites with foraging routes straightening out to connect them. However, swallows that must make long journeys over ecological barriers clearly fly at night as well as in the day, and many suggestions indicate that there is considerable complexity in the altitude and bearing of flights even during the day. There are especially intriguing indications that much swallow migration may take place high out of sight of ground observers with movements near the ground often associated with foraging in passage. Provided that roost sites can be reliably found, swallow migration can be extremely flexible, and there are interesting contrasts in the biogeography and phenological flexibility of swallows compared to other passerine birds. Even within the swallows, there is considerable interspecific and intraspecifc variability in the distances of their annual migrations...

Arquitectura de los nidos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa) construidos en cajas nido; Architecture of white-rumped swallow’s (Tachycineta leucorrhoa) nests built in nest boxes

Bulit, Florencia; Massoni, Viviana
Fonte: Revista de Ornitología Neotropical; Aves Argentinas; Aves Argentinas / Asociación Ornitológica del Plata Publicador: Revista de Ornitología Neotropical; Aves Argentinas; Aves Argentinas / Asociación Ornitológica del Plata
Tipo: info:eu-repo/semantics/article; artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em /12/2004 Português
Relevância na Pesquisa
47.55%
La arquitectura de los nidos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa) no ha sido descripta en detalle hasta el momento y posiblemente varíe con las dimensiones de la cavidad en la cual son construidos. Se describen las etapas de la construcción, la arquitectura y los elementos que componen los nidos de esta especie en cajas nido de iguales dimensiones. Las golondrinas ocuparon el 25% de la altura de la caja y construyeron la copa en el centro del espacio disponible (donde el aislamiento térmico de la temperatura externa es mayor) y nunca cerca de la entrada (donde el riesgo de predación es mayor). A medida que avanzó la temporada reproductiva, las golondrinas redujeron el tiempo de construcción de la base, iniciaron la puesta de los huevos con un número menor de plumas acolchando la copa y terminaron el nido más rápidamente; el número final de plumas en la copa y corona, sin embargo, fue mayor. No se encontró relación entre el éxito de los nidos y el avance de la temporada reproductiva o la composición de los nidos. Se compararon estos nidos con los que construye la Golondrina Bicolor (Tachycineta bicolor) en el Hemisferio Norte.; The architecture of White-rumped Swallow´s (Tachycineta leucorrhoa) nests has not been described yet...

Variables que afectan el peso de los huevos en la golondrina Ceja Blanca (Tachycineta Leucorrhoa)

Barrionuevo,Melina; Bulit,Florencia; Massoni,Viviana
Fonte: El hornero Publicador: El hornero
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2010 Português
Relevância na Pesquisa
47.25%
Los recursos que asignan las hembras a sus huevos pueden tener importantes consecuencias en la vida de los pichones. La condición física de las hembras, la abundancia de alimento, las condiciones ambientales, la cantidad de huevos por puesta y la fecha de puesta son variables que suelen afectar el tamaño de los huevos en aves passeriformes. En este trabajo se estudió el efecto de estas variables sobre el peso de los huevos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa). La abundancia de insectos aéreos se estimó usando trampas cono y trampas de acrílico. El peso de los huevos fue mayor para las hembras de mejor condición física y cuanto mayor fue la temperatura promedio durante los días previos a la puesta. Estos resultados concuerdan con los obtenidos para la Golondrina Bicolor (Tachycineta bicolor), un congénere del Hemisferio Norte.

Arquitectura de los nidos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa) construidos en cajas nido

Bulit,Florencia; Massoni,Viviana
Fonte: El hornero Publicador: El hornero
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2004 Português
Relevância na Pesquisa
47.25%
La arquitectura de los nidos de la Golondrina Ceja Blanca (Tachycineta leucorrhoa) no ha sido descripta en detalle hasta el momento y posiblemente varíe con las dimensiones de la cavidad en la cual son construidos. Se describen las etapas de la construcción, la arquitectura y los elementos que componen los nidos de esta especie en cajas nido de iguales dimensiones. Las golondrinas ocuparon el 25% de la altura de la caja y construyeron la copa en el centro del espacio disponible (donde el aislamiento térmico de la temperatura externa es mayor) y nunca cerca de la entrada (donde el riesgo de predación es mayor). A medida que avanzó la temporada reproductiva, las golondrinas redujeron el tiempo de construcción de la base, iniciaron la puesta de los huevos con un número menor de plumas acolchando la copa y terminaron el nido más rápidamente; el número final de plumas en la copa y corona, sin embargo, fue mayor. No se encontró relación entre el éxito de los nidos y el avance de la temporada reproductiva o la composición de los nidos. Se compararon estos nidos con los que construye la Golondrina Bicolor (Tachycineta bicolor) en el Hemisferio Norte.