Thesis (Ph. D.)--University of California, Riverside, 2010. / Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed May 14, 2010). Includes bibliographical references. Also issued in print.

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 48-60).

Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2012 / Sparrow-larks form a relatively small genus in the family Alaudidae and comprise only seven species distributed widely throughout Africa and parts of the Eurasian landmass. Sparrow-larks are unique amongst larks in that they are sexually dichromatic and exhibit biparental care. The chestnut-backed sparrow-lark Eremopterix leucotis is endemic to Africa with five subspecies recognized based on differences in plumage colouration. The five subspecies are distributed throughout the arid to semi-arid savannas of Africa with two subspecies (E. l. hoeschi and E. l. smithi) occurring in southern Africa. Despite their widespread occurrence and its interest for research on the evolution of characteristics in the family (e.g. being sexually dichromatic and exhibiting biparental care), very little is known of the biology and ecology of the Eremopterix larks. The chestnut-backed sparrow-lark is no exception and most of what we know of the species is based on incidental observations from a few nests. In an attempt to improve our knowledge of this interesting group of species, it was decided to study various aspects of the breeding biology and ecology, moult, vocalizations and geographical variation in the chestnutbacked sparrow-lark. The breeding biology of the chestnut-backed sparrow-lark was studied at Al3 farm (De Loskop) near Mogwadi in the Limpopo Province of South Africa from January 2008 to December 2010. Data collected during the study included: breeding seasonality, egg and clutch characteristics, duration of the incubation and nestling periods, nest-site characteristics, the roles and relative contribution of the sexes in the breeding cycle, nestling development, diet and nestling provisioning rate, and breeding success. Chestnut-backed sparrow-larks bred mostly during the dry season, which is from April to September in the study area. Nevertheless, the results revealed that breeding is bimodal with a main peak in breeding activity in late summer and autumn (March to April) and a second smaller peak in spring (September to October). The species showed geographical variation in clutch size with a mean of 1.88 eggs recorded in the study area as opposed to 1.00 recorded in the northern parts of its range. Egg dimensions compared well with measurements obtained from the Nest Record Card Scheme of the Animal Demography Unit, University of Cape Town, South Africa. The mean incubation period of 10.33 days recorded in this study compares favourably with that of other Eremopterix species viii (8–10 days), a genus with some of the shortest incubation periods amongst larks. The mean nestling period of 9.2 days (range: 8–10) in the study area was significantly less than the 10–12 days reported for populations in the northern range of the species, but it compares well with those of other sparrow-larks. Nest site characteristics, which were quantified within a 1 m2 quadrant with the nest as the centre, including nest dimensions, were consistent with those reported in the literature. Chestnut-backed sparrow-larks in the study area preferred to nest in areas with a high percentage of bare ground (median = 67.5%) and very little vegetation cover (median = 25%). Most nests faced in a southerly direction compared to nests in the north of the species’ range, which face in a north-easterly or easterly direction. The species’ preference to face the nests away from the midday sun most probably serves a thermoregulatory function to avoid excessive heat during the warmest parts of the day. Most nests (78.2%) had an apron varying in size from small and insignificant to large and well-developed. The functional significance of the apron remains a matter of conjecture and there was no association between breeding success and presence or absence of the apron. In addition, one pair constructed one nest with and another without an apron, suggesting that individual preference or characteristic is not a determinant factor in the construction of an apron. Both sexes took part in nest construction, incubation and feeding and brooding of nestlings. However, the relative contributions were not entirely symmetrical as males incubated a greater proportion (50.1%) of the time compared to females (43.1%), and the mean and median of male incubation shift lengths were longer than that of females, albeit not statistically significant. However, females made statistically significantly (P < 0.05) more nest visits to deliver food compared to males (54.6% vs. 45.5%). The average breeding success, estimated using Mayfield’s method, was 16.1% but there were inter-annual differences with the overall breeding success in 2010 being only 8.1% compared to 20.6% of 2008. Known causes of failure included nest depredation, flooding, starvation, nest abandonment and hatching failure. Statistical analysis of morphometric data of live specimens and museum study skins suggest that, in addition to being sexually dichromatic, chestnut-backed sparrowlarks also exhibit mild sexual size dimorphism. However, there was considerable overlap in these measurements between the sexes and as a result the biological significance of this sexual size dimorphism may be negligible. Nevertheless, the ix results show chestnut-backed sparrow-lark males tend to have longer wings and tails compared to females. This may be adaptive with respect to the extended display flights that males perform during the breeding season. Interestingly, the mean mass of breeding females in the study area was significantly more compared to males, whereas the SAFRING database, representing data recorded throughout the year, showed no significant differences in the mean mass between the sexes. The greater mass of breeding females may relate to physiological changes associated with the acquisition of resources and the development of structures and tissues associated with egg-laying and egg-production. Larks rely heavily on vocalizations to attract mates and advertise territories. Not surprisingly, the study revealed a rich vocal repertoire for the chestnut-backed sparrow-lark. The analysis of the vocalizations shows that chestnut-backed sparrowlarks have a display song performed by males, a sub-song sung by both sexes and various different calls used in different contexts, e.g. flight and alarm calls. The study also presents the first analysis and description of the vocalizations of nestlings. An interesting feature of the vocalizations of the chestnut-backed sparrow-larks was that they performed hetero-specific vocal mimicry, which was incorporated in the subsong. Moult is a relatively unknown aspect in the annual cycle of the majority of larks. Chestnut-backed sparrow-larks undergo post-breeding moult, which is an adaptation to reduce the conflict between moult and breeding as both activities have high energy demands. The moult study also showed that they undergo a partial moult in mid-winter, involving the inner-most secondaries and some of the contour feathers. The results of this study shed valuable light on the natural history of this species and contributed significantly to ornithology and our growing understanding of the biology and ecology of the family. The results can also form a basis for future inter- and intraspecific comparative studies. The study illustrates the importance of undertaking long term studies of species to account for inter-annual differences in various ecological parameters.

Structure of songs and organization of singing in 133 Fox Sparrows Passerella iliaca were studied during 2 breeding seasons in 3 geographically separate populations in northern Utah and southern Idaho. The structure of songs was analyzed with the aid of an audiospectrograph. The organization of the singing of songs in 56 birds was analyzed by applying Markov chain analyses to the sequences of songs uttered. Songs were composed of sy lla bl e- types , of which 49 were recognized. Syllabl e- types could occur sing ly or be seria lly repeated within songs, but they were never fractured so that onl y a portion of one wo ul d be in evidence. Songs were categorized into 5 major types (A, B, C, D, and E) on the basis of the uniformity amo ng individuals in the sequences of sy llable-types which were used to form so ngs . Most song-types were easily characterized by a particular sequence of syllable- types used in forming the terminal portions of the songs, but song-type D was most easily characterized by a sequence of syllable-types near the beginning of the song. Although the sequences of syllable-types forming songs were sufficiently distinct so that the songs could be assigned to a particular major song-type, there were consistent variations among individuals in the sequences of syllable-types composing their songs. Such variants were termed song-versions. The variation in the syllable-types composing songs tended to be restricted to the first halves of the songs. About one half of all the individuals recorded sang more than one version of some particular song-type, usually B or C. Individual birds used a mean number of 8.2 syllable-types in the formation of each song. The mean number of syllable-types used in forming song-types A, B, C, D, and E in 1973 and 1974 were 7.5 -7.7, 8.5-7.6, 7.8-7.8, 9.4-9.4, and 9.0-7.5, respective ly. Few variations were evident among individuals in the mean number of syllable-types or song-types that constituted their repertoires. Differences in the mean number of syllable-types composing similar song-types were al so of little magnitude. Significant differences were evident in the number of syllable-types possessed by individuals having repertories of 2, 3, and 4 songs. Those birds which possessed the largest repertoires of songs exhibited the greatest number of syllable-types. Six color-banded individuals did not change the size or structure of their syllable-type or song-type repertoires during the year or between years. Singing was organized into discrete bouts in which each song of an individual tended to be presented with equal frequency of occurrence. The ordering of songs within singing bouts occurred in particular sequences, with each song being sung once. After a bird had sung all of its songs once, it would begin the sequence over again. The order in which a bird presented its songs did not change with the passage of time, it was not related to the song-types the bird possessed, and it did not appear to be affected by the sequence of songs being sung by neighboring Fox Sparrows. Markov cha in analysis of the ordering of songs described the sequencing as a first-order Markov chain in all but three birds. A higher order Markov chain was most appropriate for those three birds which were not described by a first-order Markov chain. Intra- and interpopulation variations in most of the parameters of song which were considered demonstrated little variation within any of the 3 populations between years or among populations in either of the 2 years . Cluster analyses of the geographic distribution of syllabletypes and song-types reiterated that the incidence of syllable-types and song-types tended to be uniform within and among the populations. The most distinctive group of individuals, based upon the presence or absence of syllable-types and song-types, was the northernmost population. The southernmost population of birds tended to demonstrate the most variability in their possession of syllable-types and song-types. Comparison of the structure of song in Fox Sparrows with other species of the Emberizidae showed that Fox Sparrows' song structuring was not directly analogous to that of any other emberizid, although the structures of Fox Sparrow songs and syllable-types were not sufficiently different that they could not be recognized as belonging to a member of the Emberizidae. The structure of Fox Sparrow song is most similar to that of their nearest relatives, Melospiza, especially M. melodia, whereas song structuring in Fox Sparrows is less similar to that in the species of the genera Zonotrichia and Junco. The variations which were present in the structure of individuals' songs and the geographic distributions of syllable-types and song-types were considered to reflect geographic variation rather than dialects. It is proposed that Fox Sparrows learn their songs early in life, as does Zonotrichia leucophrys, and that song may encode messages which allow others to recognize the singer's sex, location, marital status, motivation, and species and individual identity. It is suspected that Fox Sparrow songs do not have great capability of conveying the population affiliation of the singer. It is proposed that the various songs of individual Fox Sparrows are of equal valence with respect to intraspecific interactions, and that this suspicion associated with other factors concerning the organization of singi ng in Fox Sparrows indicates the order in which a bird presents its songs is learned early in life and it is retained unaltered.

Islands are valuable research systems for evolution and conservation, but most work has focused on oceanic islands. Far less study has occurred on near-shore islands where inter-island and island-mainland dispersal is an important microevolutionary process. Further studies in near-shore systems would aid the expansion of island evolutionary theory and conservation initiatives. In this thesis, I studied populations of Song Sparrows (Melospiza melodia) on near-shore islands along the Pacific coast of North America to examine the causes and consequences of dispersal for microevolutionary and ecological processes. Within an island metapopulation, where inter-island distances ranged from 200m to 2km, male and female immigration rates were influenced by adult density and sex ratio respectively, suggesting that intrasexual territoriality influences immigration. Islands differed in immigration levels, with low immigration and high resident recruitment on more isolated islands. I next examine genetic structuring at a larger spatial scale (0-300km). I found that the scale of genetic structuring within continuously distributed populations was less than 10km, suggesting that Song Sparrows are a sedentary passerine. Regional comparisons revealed that holding geographic distance constant, larger genetic distances occur in areas located at subspecific boundaries or across water barriers. The apparent reduction in dispersal to islands had broad-scale consequences. Across Pacific Coast islands, island populations consistently had lower genetic variation than mainland populations. Small and remote island populations tended to have the lowest genetic variation. From an in situ conservation stance, populations on large, remote islands could be important contributors to intraspecific genetic diversity because of high genetic differentiation. Finally, I link genetic structuring with contemporary dispersal and show that migration rates among the Channel Islands are low, suggesting that these islands are demographically independent. The absence of shared mtDNA haplotypes between extant and extinct populations suggests that inter-island migration was historically low, potentially explaining why the two extirpated islands have not been recolonized. Collectively, my thesis results increase our understanding of the mechanisms of divergence on insular populations by examining factors affecting dispersal, the spatial scale of divergence and estimating the consequences of reduced gene flow on islands for broad-scale patterns of genetic variation, microevolution and demographic stability.

Free-living vertebrates likely encounter many stressors throughout their lifetime, from fighting off a predator to coping with unpredictable weather. As a result, vertebrates will mount an acute response to the stressors. Here, we outline previous research conducted in behavioral endocrinology and stress physiology as it relates to our research. We then discuss our study with white-crowned sparrows (Zonotrichia leucophrys) in Tioga Pass Meadow, in which we examined how the acute stress response affects foraging behavior 24 hours after a stressor. In birds that underwent a stress series, we found there to be a significant 57% decrease in foraging behavior 24 hours following the stressor. Additionally, we found no significant difference in foraging of unstressed birds during this same time frame. Our findings suggest that the acute stress response in this species causes a reduction in foraging activity 24 hours following a stressful event.

Islands are valuable research systems for evolution and conservation, but most work has focused on oceanic islands. Far less study has occurred on near-shore islands where inter-island and island-mainland dispersal is an important microevolutionary process. Further studies in near-shore systems would aid the expansion of island evolutionary theory and conservation initiatives. In this thesis, I studied populations of Song Sparrows (Melospiza melodia) on near-shore islands along the Pacific coast of North America to examine the causes and consequences of dispersal for microevolutionary and ecological processes. Within an island metapopulation, where inter-island distances ranged from 200m to 2km, male and female immigration rates were influenced by adult density and sex ratio respectively, suggesting that intrasexual territoriality influences immigration. Islands differed in immigration levels, with low immigration and high resident recruitment on more isolated islands. I next examine genetic structuring at a larger spatial scale (0-300km). I found that the scale of genetic structuring within continuously distributed populations was less than 10km, suggesting that Song Sparrows are a sedentary passerine. Regional comparisons revealed that holding geographic distance constant, larger genetic distances occur in areas located at subspecific boundaries or across water barriers. The apparent reduction in dispersal to islands had broad-scale consequences. Across Pacific Coast islands, island populations consistently had lower genetic variation than mainland populations. Small and remote island populations tended to have the lowest genetic variation. From an in situ conservation stance, populations on large, remote islands could be important contributors to intraspecific genetic diversity because of high genetic differentiation. Finally, I link genetic structuring with contemporary dispersal and show that migration rates among the Channel Islands are low, suggesting that these islands are demographically independent. The absence of shared mtDNA haplotypes between extant and extinct populations suggests that inter-island migration was historically low, potentially explaining why the two extirpated islands have not been recolonized. Collectively, my thesis results increase our understanding of the mechanisms of divergence on insular populations by examining factors affecting dispersal, the spatial scale of divergence and estimating the consequences of reduced gene flow on islands for broad-scale patterns of genetic variation, microevolution and demographic stability.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 91-106).

Islands are valuable research systems for evolution and conservation, but most work has focused on oceanic islands. Far less study has occurred on near-shore islands where inter-island and island-mainland dispersal is an important microevolutionary process. Further studies in near-shore systems would aid the expansion of island evolutionary theory and conservation initiatives. In this thesis, I studied populations of Song Sparrows (Melospiza melodia) on near-shore islands along the Pacific coast of North America to examine the causes and consequences of dispersal for microevolutionary and ecological processes. Within an island metapopulation, where inter-island distances ranged from 200m to 2km, male and female immigration rates were influenced by adult density and sex ratio respectively, suggesting that intrasexual territoriality influences immigration. Islands differed in immigration levels, with low immigration and high resident recruitment on more isolated islands. I next examine genetic structuring at a larger spatial scale (0-300km). I found that the scale of genetic structuring within continuously distributed populations was less than 10km, suggesting that Song Sparrows are a sedentary passerine. Regional comparisons revealed that holding geographic distance constant, larger genetic distances occur in areas located at subspecific boundaries or across water barriers. The apparent reduction in dispersal to islands had broad-scale consequences. Across Pacific Coast islands, island populations consistently had lower genetic variation than mainland populations. Small and remote island populations tended to have the lowest genetic variation. From an in situ conservation stance, populations on large, remote islands could be important contributors to intraspecific genetic diversity because of high genetic differentiation. Finally, I link genetic structuring with contemporary dispersal and show that migration rates among the Channel Islands are low, suggesting that these islands are demographically independent. The absence of shared mtDNA haplotypes between extant and extinct populations suggests that inter-island migration was historically low, potentially explaining why the two extirpated islands have not been recolonized. Collectively, my thesis results increase our understanding of the mechanisms of divergence on insular populations by examining factors affecting dispersal, the spatial scale of divergence and estimating the consequences of reduced gene flow on islands for broad-scale patterns of genetic variation, microevolution and demographic stability. / Forestry, Faculty of / Graduate

While in no way passing judgments on the quality of the investigations which have been published, there is one conclusion that must be reached and this is that there is room for further investigations. The studies which form the basis of this paper were undertaken to widen the general range of information on the avian kidney and its associated osseous cradle. In addition to the discussion, numerous photographs and diagrams are submitted to clarify and support the text. The present paper deals with with kidney and pelvic girdle of two species of sparrow: Zonotrichia leucophrys and Passer domesticus.