This thesis presents the results of a study on the Swallow Hirundo rustica carried out in Central Scotland between April 1986 and August 1989. Their social behaviour and life history are described. Adults were found to be markedly faithful to both their mate and site. Notable differences between results observed here and with other similar studies were the apparent lack of any sexually selected infanticide or intra-specific nest parasitism. These results were attributed to differences in colony size. Intra- and inter-sexual variation in adult body size was measured and the presence of any age-related trends identified. Older birds had significantly bigger wing and outertail lengths but skeletal measures and inner tail-length did not vary in size. Swallows were found to be sexually size dimorphic for several parameters and these findings were discussed in relation to three hypotheses. Variation in reproductive performance between years and individuals was described. Clutch size and number of young fledged was lower for second- than first-broods but even after controlling for this, breeding performance still declined seasonally. Possible mechanisms associated with this common finding were explored. The number of broods attempted in a season made an important contribution to seasonal reproductive performance. Double brooded Swallows: (i) bred earlier, (ii) were older and (iii) were more successful during their first brood (cf. single-brooded). Since any measure of seasonal performance is likely to be an incomplete measure of fitness, attention was also given to understanding what factors affected adult and juvenile survival. Offspring which hatched earliest and from first broods were most likely to be recruited. There was no evidence to support a positive association between fecundity and parental survival in Swallows studied here, however. The role of individual characteristics in shaping reproductive performance was examined. Body size was only weakly associated, whereas parental age was strongly correlated with breeding success; yearlings laid later, had smaller clutch sizes and fledged fewer young during a season. Although females which were monitored over two successive seasons laid earlier in their second season they did not differ significantly for any other parameter compared. Data from other studies were reviewed and possible hypotheses to explain age-related trends were considered. It was concluded that the improved performance of older Swallows was related at least in part to individual differences and selective mortality. In an attempt to manipulate reproductive effort brood sizes were experimentally altered by adding (Enlarged) or removing (Reduced) one, two or three nestlings shortly after hatch. Un-manipulated broods served as Controls. The size of the first brood reared affected the probability that a second clutch would be laid as well as the timing (IBI) and, (iii) success (but not size) of the second clutch. The effect of manipulation on the IBI and occurrence of second brood was asymmetrical. Temporal variation, however, could not explain differences in future fecundity between first brood treatment categories. Early desertion in relation to clutch or brood reduction was discussed in relation to the "Concorde Fallacy". Although most pairs were able to rear additional young, nestling quality was adversely affected. Juvenile survival was related to brood size such that parents which reared Control broods were most likely to produce recruits. Manipulation of brood size also had an effect on adult survival but the effect differed between sexes and broods. The clearest and most significant result was that Swallows which reared Reduced broods (first or second) were more likely to survive (cf. Control or Enlarged broods). These findings were not attributed to differential dispersal of adults. A review of the literature indicated that this was the first study to publish results on the possible effects of manipulation of second broods for parental survival. The pattern of adult body mass during the nesting cycle was described. Males and females reached a minimum mass when the nestlings were aged between Days 9and 16 (NP II) and Days 17-23 (NP III) respectively. Only during these two stages were males heavier than females. Possible implications associated with a decrease in mass while feeding nestlings (cf. incubation) were discussed. Analyses of a sample of adult carcasses enabled body condition to be determined precisely. Quantitative methods of assessing the condition of live birds in the field were developed and validated against carcass analysis results. Muscle thickness as measured by a portable ultra-sound device and body mass were both considered to give reliable estimates of condition. A number of predictions following from the assumption that parental condition was related to current and future fecundity or overwinter survival were tested. There appeared to be no significant relationship between condition while feeding first brood nestlings and, a) the IBI, or b) occurrence of second broods. This applied to parents rearing both natural and experimental broods. There was some evidence to suggest that the condition of parents after the brood had fledged might be of greater importance. More data are necessary to confirm this finding, however. Female condition at any stage in the nesting cycle (lst or 2nd brood) was not related to overwinter survival. Data for males, however, supported the prediction such that birds in poorer condition during NP II were less likely to survive. Possible reasons for differences between the sexes were explored. One suggestion proposed was that females were better able to regulate their effort to maximise fitness and and so males were possibly "victims" of their partners variability. The possibility that single- and double-brooded species may vary in their allocation of resources was considered and there was some evidence to support this suggestion for Swallows observed here.

The use of precision automated electronic balances has allowed remote quantification of instantaneous and long term body mass changes in breeding swallows, Hirundo rustica. By means of observation, experiment and optimality modelling, the extent of mass changes during incubation and nestling rearing are described, and the fitness consequences of mass changes discussed. An understanding of the causes and consequences of mass changes in swallows is developed from laboratory investigations of short term mass changes in canaries Serinus canarius, and from carcass analysis of breeding sand martins R. riparia, and swallows. Parent: offspring resource allocation was investigated during incubation in swallows. A model is developed which assumes that fitness is maximised in individuals which spend most time on the nest as a result of maximising the difference between net gain while foraging and clutch reheating costs, measured in units of energy. The model is tested, and the most frequently observed inattentive period proves, to be similar to that predicted to be the most energetically profitable. The early decline in swallow body mass during nestling rearing is likely to represent a 'programmed' anorexia in females during the brooding phase, whereby mass loss is beneficial in reducing flight costs and releasing energy available for work. After termination of brooding, however, mass losses were associated with rapid feeding rates to the brood for both sexes, and were judged to be potentially costly in terms of adult survival. (ii) By concurrent monitoring of resources for parents and offspring, investment in self-maintenance relative to investment in offspring is calculated, and the results interpreted in the wider context of lifehistory tactics and parental investment theories. Both sexes of swallow invested more in 'self' relative to 'offspring' when food was scarce or when feeding broods of small metabolic mass. Females appeared to risk their body mass falling to lower levels than that of their mates when feeding conditions were poor. overall, the study showed that the costs and benefits of mass changes in swallows differed according to the stage of the breeding cycle, and that detailed knowledge of the causes of mass changes allows insight into the evolution of reproductive strategies of birds of both sexes in relation to individual quality and resource availability.

Thesis (M. Sc.)--York University, 1997. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 24-31). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ27365.

Sexual selection can be defined as the difference in reproductive success among individuals that is related to their ability to acquire mates and fertilizations. Mathematical models have shown that combined with natural selection, sexual selection can be an important driver for speciation. There have also been a few case studies showing that sexual selection alone can lead to speciation in nature. Over the past 30 years, the barn swallow has become a classic model animal for sexual selection. The barn swallow has at least two sexually selected traits in different subspecies: the length of tail streamers in European barn swallows, H. r. rustica and ventral plumage colour in north American barn swallows, H. r. erythrogaster. Meanwhile molecular research on barn swallows shows that these barn swallow subspecies are recently derived and thus the barn swallow becomes an ideal model animal to test the theory that sexual selection drives speciation. The Barn Swallow species complex is comprised of six closely related subspecies distributed throughout the Holarctic. Whereas experimental studies in Europe, the Middle East and North America have been conducted, little is known about populations distributed across Asia. During my PhD study I collected barn swallow samples from more than 20 locations across China and compared the difference in morphology of Chinese barn swallow populations. The results show that in the northeastern part of China the barn swallow is intermediate in phenotype between subspecies in North America (H. r. erythrogaster) and subspecies in Europe (H. r. rustica), and is characterized by rusty ventral plumage colour and medium length tail streamers. Using morphological and colour traits, northeastern Chinese swallow populations can be separated from other Chinese populations, and this pattern of phenotypic variation may form under both natural and sexual selection. I also conducted an observational and experimental study on one of these populations, aiming to determine the extent to which variation in plumage color and tail streamers is underlain by sexual selection. The observational study reveals that for male barn swallows in my study population, clutch initiation date, the number of both social and genetic offspring and the body condition of nestlings can be predicted by the colouration of their ventral plumage, while the experiment shows that the reproductive success of male barn swallows tended to increase with experimental enhancement on their plumage colouration. My research supports that the ventral plumage colour is the sexually selected trait in northeastern Chinese barn swallows, and further experiments are needed to clarify the effect of male ventral plumage colour manipulation on their breeding success with the limitation of small sample size in my study.

Oil sands mining companies in Alberta, Canada, are planning to create wetlands for the bioremediation of mining waste materials as part of a reclamation strategy. To assess feasibility, experimental wetlands mimicking proposed reclamation scenarios were constructed on mining leases. This research assessed the health of tree swallows (<i>Tachycineta bicolor</i>) nesting on these sites where they were naturally exposed to a mixture of chemicals including unrecovered bitumen, naphthenic acids (NAs) and polycyclic aromatic hydrocarbons (PAHs). Endpoints reflecting health were compared among three experimental wetlands and one reference site. In order to specifically investigate toxicity of NAs to birds, an experimental exposure to NAs was also conducted on a subset of nestlings on the reference site. <p> In 2003 and 2004, approximately 50 breeding pairs (total, per year) nesting on the following sites were monitored: Suncors Consolidated Tailings and Natural Wetlands; Syncrudes Demo Pond and Poplar Creek reference site. In 2003, reproductive success was very low on OSPM-sites compared to the reference site, but was relatively unaffected in 2004. Compromised reproductive performance in 2003 was linked to harsh weather, during which mortality rates of nestlings reached 100% on the site with the highest levels of PAHs and NAs, while they did not surpass 50% on the reference site. In 2004, mortality rates were low but nestlings from OSPM-sites weighed less and showed greater hepatic detoxification efforts (etoxyresorufin-o-deethylase activity) than those on the reference site. Furthermore, nestlings on OSPM-sites exhibited higher levels of thyroid hormones and suffered parasitic burdens (Protocalliphora spp.) approximately twice that of those on the reference site. Several of these findings may be associated with low post-fledging survival, suggesting that wet landscape reclamation strategy is not optimal for avian species and may require improvement. <p> As part of a separate study investigating toxicity of naphthenic acids, twenty nestlings from the reference site were randomly selected for an experimental exposure. Nestlings received 0.1 ml/day of NAs (15g/L) orally from day 7 to day 13 of age while being reared normally by their free-ranging parents. Nestling growth, hematocrit, blood biochemistry, organ weights and etoxyresorufin-o-deethylase activity (EROD) activity appeared unaffected by naphthenic acids. No toxic changes were detected on histopathological evaluation of major organs. These findings suggest that for nestlings reared on oil sands reclaimed sites, exposure to other chemicals such as polycyclic aromatic hydrocarbons is a greater concern than exposure to NAs. However, this study did not investigate the chronic or reproductive toxicity of naphthenic acids. More research still needs to be conducted as a part of an assessment of the sustainability of wet landscape reclamation because a previous study found that chronic exposure to NAs severely compromised reproduction in mammals.

Oil sands mining companies in Alberta, Canada, are planning to create wetlands for the bioremediation of mining waste materials as part of a reclamation strategy. To assess feasibility, experimental wetlands mimicking proposed reclamation scenarios were constructed on mining leases. This research assessed the health of tree swallows (<i>Tachycineta bicolor</i>) nesting on these sites where they were naturally exposed to a mixture of chemicals including unrecovered bitumen, naphthenic acids (NAs) and polycyclic aromatic hydrocarbons (PAHs). Endpoints reflecting health were compared among three experimental wetlands and one reference site. In order to specifically investigate toxicity of NAs to birds, an experimental exposure to NAs was also conducted on a subset of nestlings on the reference site. <p> In 2003 and 2004, approximately 50 breeding pairs (total, per year) nesting on the following sites were monitored: Suncors Consolidated Tailings and Natural Wetlands; Syncrudes Demo Pond and Poplar Creek reference site. In 2003, reproductive success was very low on OSPM-sites compared to the reference site, but was relatively unaffected in 2004. Compromised reproductive performance in 2003 was linked to harsh weather, during which mortality rates of nestlings reached 100% on the site with the highest levels of PAHs and NAs, while they did not surpass 50% on the reference site. In 2004, mortality rates were low but nestlings from OSPM-sites weighed less and showed greater hepatic detoxification efforts (etoxyresorufin-o-deethylase activity) than those on the reference site. Furthermore, nestlings on OSPM-sites exhibited higher levels of thyroid hormones and suffered parasitic burdens (Protocalliphora spp.) approximately twice that of those on the reference site. Several of these findings may be associated with low post-fledging survival, suggesting that wet landscape reclamation strategy is not optimal for avian species and may require improvement. <p> As part of a separate study investigating toxicity of naphthenic acids, twenty nestlings from the reference site were randomly selected for an experimental exposure. Nestlings received 0.1 ml/day of NAs (15g/L) orally from day 7 to day 13 of age while being reared normally by their free-ranging parents. Nestling growth, hematocrit, blood biochemistry, organ weights and etoxyresorufin-o-deethylase activity (EROD) activity appeared unaffected by naphthenic acids. No toxic changes were detected on histopathological evaluation of major organs. These findings suggest that for nestlings reared on oil sands reclaimed sites, exposure to other chemicals such as polycyclic aromatic hydrocarbons is a greater concern than exposure to NAs. However, this study did not investigate the chronic or reproductive toxicity of naphthenic acids. More research still needs to be conducted as a part of an assessment of the sustainability of wet landscape reclamation because a previous study found that chronic exposure to NAs severely compromised reproduction in mammals.

The contamination of inland surface water by point and nonpoint sources is a widespread human health concern. To address this problem, a thorough understanding of the sources and persistence of this pollution is necessary. Using fecal indicator bacteria (FIB) as a surrogate for enteric pathogens, the Environmental Protection Agency (EPA) and state agencies have developed surface water quality standards. If a segment does not meet these standards, a Total Maximum Daily Load (TMDL) must be developed for the watershed to identify sources of bacterial pollution. Currently, FIB pollution is the leading pollution type addressed by TMDLs in the country. One source of FIB identified in TMDLs is colonies of birds roosting under bridges. It has been proposed that the birds’ feces can augment the FIB concentrations downstream of bridges. In this year-long study of Bull Creek in Austin, Texas, it was determined that the concentrations of Escherichia coli and fecal coliform downstream of a bridge were significantly greater when migratory cliff swallows were nesting under the bridge. The downstream concentrations of both FIB exceeded contact recreation standards. Data also suggest that FIB from the feces could be swept into the stream by runoff from storm events. No enterococci loading was observed in conjunction with the swallows. This study also investigated the affects of sediment resuspension on surface water FIB concentrations and the persistence of FIB in shady, inland streams. The resuspension of sediments with attached FIB could also increase the FIB concentration in the water column and increase its persistence. The results of reactor-based experiments demonstrated that the concentration of E. coli in water from an effluent-dominated stream increased by a factor of 3 when riverine sediments were resuspended and exceeded single sample standards for contact recreation, suggesting sediments as a reservoir of E. coli. Additionally, concentrations of E. coli decreased by approximately 90% and 70% over 2 days in reactors containing stream water and sediment-laden stream water, respectively. / text

There is growing evidence of carry-over effects in migratory birds. Aerial insectivores are declining across North America; therefore, to determine the cause of these declines, we must have a holistic view of their annual cycle. I use geolocators to map the annual movements of tree swallows breeding in Nova Scotia, Canada, determine if reproduction has carry-over effects on migration, and examine the effects of geolocators. Geolocators revealed that tree swallows began migration in July and had an extended stopover in the northeastern United States. They wintered in Florida or Cuba, returning from spring migration in late April. This study revealed that later breeding swallows began migration later than earlier breeding swallows, but all birds arrived on the wintering grounds around the same time, due to differences in stopover length. No short-term effects of geolocators were found, although the sample size was small, and thus these results must be interpreted cautiously.

Made available in DSpace on 2015-05-14T16:53:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-20Bitstream added on 2015-05-14T16:59:22Z : No. of bitstreams: 1 000821544.pdf: 1058654 bytes, checksum: 3c5b3272b062e9f435343490ca99ea7e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Dentre as diferentes tecnologias utilizadas para avaliação instrumental da deglutição orofaríngea, tendo como critério a relação custo/benefício, a ultrassonografia do movimento de língua se destaca como um instrumento viável para a investigação das funções orofaciais. O objetivo desse estudo é descrever e caracterizar qualitativamente e quantitativamente os parâmetros ultrassonográficos da deglutição orofaríngea em adultos saudáveis e verificar de que forma as variáveis faixa etária e consistência de alimento, bem como suas respectivas interações, interferem nos parâmetros ultrassonográficos. Foram realizadas avaliações ultrassonográficas da deglutição (com ultrassom portátil modelo DP 6600, transdutor micro-convexo acoplado a um computador, além do estabilizador de cabeça) de 100 indivíduos (divididos em 4 grupos: GI - 20 à 30 anos, GII - 31 à 40 anos, GIII - 41 à 50 anos e GIV - 51 à 60 anos) com a consistência líquida (volume livre e controlado de 5ml) e consistência pudim (volume controlado de 5ml). Os parâmetros para a análise qualitativa do movimento de língua e do osso hióide foram adaptados de um estudo prévio. Considerou-se a presença de cinco marcadores durante a deglutição orofaríngea. Para a análise quantitativa, foram observados os parâmetros: duração da propulsão do movimento de língua durante a deglutição e a distância do deslocamento máximo do osso hióide durante o pico da deglutição. Os resultados indicaram que, em relação à descrição ultrassonográfica qualitativa, todos os indivíduos, independente da consistência e volume do alimento apresentaram o mesmo padrão de postura de língua para a recepção do alimento (fase1) e apreensão do alimento (fase 2). Em relação à propulsão do bolo alimentar (fase 3), verificou-se uma grande variabilidade inter-sujeitos do movimento ondulatório da língua. Já para o pico máximo do deslocamento... / Among different technology used in oropharyngeal swallowing instrumental evaluation, considering cost-benefit ratio, tongue movement ultrasound stand out as a viable instrument to investigate orofacial functions. This study aims to describe and to define - both qualitatively and quantitatively - ultrasonographic parameters of oropharyngeal swallowing among healthy adults and to verify in what way the variables age group and consistency of food swallowed, as well as respective interactions, might interfere with ultrasonographic parameters. Ultrasonographic evaluations of swallowing were performed (using the DP 6600 portable ultrasound machine, a micro-convex probe connected to a PC, and a Stabilization Headset) in 100 people (divided into four groups: GI - 20 à 30 age, GII - 31 à 40 age, GIII - 41 à 50 age e GIV - 51 à 60 age), using liquids (both free volume and controlled swallow of 5 ml) and pudding-consistent food (controlled swallow of 5 ml). Tongue and hyoid bone movement, used as parameters to qualitative analysis, were adapted from a previous study. During the oropharyngeal swallowing, the presence of five markers was considered. The following parameters were regarded in the quantitative analysis: tongue movement propulsion duration during swallowing, and maximum displacement of the hyoid bone during swallowing peak. Considering qualitative ultrasonographic description, the results pointed that all volunteers presented the same standard tongue posture previous to food reception (phase 1) and containment (phase 2), regardless of food consistency and volume. During the bolus propulsion (phase 3), a wide intersubjective variety of wavelike movements was observed. Concerning maximum displacement of the hyoid bone (phase 4), the ultrasonographic image was analyzed having as reference a 45º angle, that is, for each kind of bolus, we considered displacements equal or under 45º, or above this. Generally, the angle ...

Orientadora: Larissa Cristina Berti / Co-orientadora: Roberta Gonçalves da Silva / Banca: Jeniffer de Cássia Rillo Dutka / Banca: Luciana Pinato / Resumo: Dentre as diferentes tecnologias utilizadas para avaliação instrumental da deglutição orofaríngea, tendo como critério a relação custo/benefício, a ultrassonografia do movimento de língua se destaca como um instrumento viável para a investigação das funções orofaciais. O objetivo desse estudo é descrever e caracterizar qualitativamente e quantitativamente os parâmetros ultrassonográficos da deglutição orofaríngea em adultos saudáveis e verificar de que forma as variáveis faixa etária e consistência de alimento, bem como suas respectivas interações, interferem nos parâmetros ultrassonográficos. Foram realizadas avaliações ultrassonográficas da deglutição (com ultrassom portátil modelo DP 6600, transdutor micro-convexo acoplado a um computador, além do estabilizador de cabeça) de 100 indivíduos (divididos em 4 grupos: GI - 20 à 30 anos, GII - 31 à 40 anos, GIII - 41 à 50 anos e GIV - 51 à 60 anos) com a consistência líquida (volume livre e controlado de 5ml) e consistência pudim (volume controlado de 5ml). Os parâmetros para a análise qualitativa do movimento de língua e do osso hióide foram adaptados de um estudo prévio. Considerou-se a presença de cinco marcadores durante a deglutição orofaríngea. Para a análise quantitativa, foram observados os parâmetros: duração da propulsão do movimento de língua durante a deglutição e a distância do deslocamento máximo do osso hióide durante o pico da deglutição. Os resultados indicaram que, em relação à descrição ultrassonográfica qualitativa, todos os indivíduos, independente da consistência e volume do alimento apresentaram o mesmo padrão de postura de língua para a recepção do alimento (fase1) e apreensão do alimento (fase 2). Em relação à propulsão do bolo alimentar (fase 3), verificou-se uma grande variabilidade ... (Complete abstract click electronic access below) / Abstract: Among different technology used in oropharyngeal swallowing instrumental evaluation, considering cost-benefit ratio, tongue movement ultrasound stand out as a viable instrument to investigate orofacial functions. This study aims to describe and to define - both qualitatively and quantitatively - ultrasonographic parameters of oropharyngeal swallowing among healthy adults and to verify in what way the variables age group and consistency of food swallowed, as well as respective interactions, might interfere with ultrasonographic parameters. Ultrasonographic evaluations of swallowing were performed (using the DP 6600 portable ultrasound machine, a micro-convex probe connected to a PC, and a Stabilization Headset) in 100 people (divided into four groups: GI - 20 à 30 age, GII - 31 à 40 age, GIII - 41 à 50 age e GIV - 51 à 60 age), using liquids (both free volume and controlled swallow of 5 ml) and pudding-consistent food (controlled swallow of 5 ml). Tongue and hyoid bone movement, used as parameters to qualitative analysis, were adapted from a previous study. During the oropharyngeal swallowing, the presence of five markers was considered. The following parameters were regarded in the quantitative analysis: tongue movement propulsion duration during swallowing, and maximum displacement of the hyoid bone during swallowing peak. Considering qualitative ultrasonographic description, the results pointed that all volunteers presented the same standard tongue posture previous to food reception (phase 1) and containment (phase 2), regardless of food consistency and volume. During the bolus propulsion (phase 3), a wide intersubjective variety of wavelike movements was observed. Concerning maximum displacement of the hyoid bone (phase 4), the ultrasonographic image was analyzed having as reference a 45º angle, that is, for each ... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre