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The sexes have different life histories that can influence their parental care strategies. I studied northern flicker, Colaptes auratus, parents and simultaneously radio-tracked mates during the nestling and post-fledging periods. I tested hypotheses about sex differences in parental care strategies by examining foraging patterns, provisioning effort and habitat use. Males and females used the same microhabitats, but avoided overlap of their foraging areas on the home range consistent with the hypothesis that mates separate the home range to reduce competition. During temporary (i.e., 24 hr) brood size manipulations, both parents decreased provisioning to reduced broods, but did not increase provisioning to enlarged broods or alter their foraging pattern on the landscape. I suggest flickers were energy limited and were incapable or unwilling to respond to increased brood demands. During the post-fledging period, males spent more time near their fledglings, and cared for their fledglings longer than females (16 days versus 12 days, respectively). Approximately 36% of females abandoned their brood in the post-fledging period and females with high levels of feather corticosterone were more likely to abandon. Older males and those with high provisioning rates in the nestling period fed their fledglings longer. Nearly 45% of fledglings died within the first week after leaving the nest, but survival was higher for fledglings with intermediate body mass and those that occupied areas of dense cover. Families moved a greater distance from the nest during the first 4 days post-fledging when there was less tree cover within 250 m of the nest site. Parents brought fledglings to areas with dense vegetation within the first week post-fledging, but subsequently shifted to open grassland habitats. My results show that parents invest in their offspring indirectly by taking them to habitats that increase survival. This research stresses the importance of studying parental care during the post-fledging period to gain a more complete understanding of the total parental investment of males versus females and how each sex may react differently to trade-offs between investing in the current brood versus self-maintenance.

Many factors affect the productivity of songbirds. Which vegetation types the birds inhabit, nest-site characteristics, and adult behavior at the nest may affect predation and parasitism frequencies, fecundity, and nest survival and fledgling survival. All of these metrics determine reproductive success of individuals and may influence population persistence, especially for threatened and endangered species. My research investigated factors that affected these metrics for endangered black-capped vireos (Vireo atricapilla). Shrubland is considered high quality vireo habitat, with woodland vegetation types considered marginal. I located and monitored nests, conducted nest behavior observations, recorded behavior and predation at nests using video cameras, and resighted fledglings in shrubland, oak-juniper woodland, and deciduous woodland during the 2008–2010 breeding seasons. I monitored 302 black-capped vireo nests in 259 territories and resighted 350 fledglings with unique color combinations. Apparent nest success, nest survival, success of first nest attempts, parasitism and predation frequency, and fecundity did not differ statistically among vegetation types. Parasitism frequency was nearly twice as high in shrubland (22 percent) than in either woodland (12 percent in each) and varied by year. Nest-site characteristics differed among vegetation types, but nest survival was affected only by nest height and year; nests placed higher from the ground and nest attempts in 2008 and 2009 had lower survival. Fledgling survival was not affected by vegetation type or proximity of the nest to oak-juniper woodland. Nest behavior was not affected by vegetation characteristics, though nest attentiveness during incubation increased as average cover from 0 to 2 m increased. Females spent 80 percent more time on nests during incubation and 250 percent more time on nests during the nestling stage than males, but visitation was similar for each sex. Overall, the probability of nest success improved as male participation increased. My results emphasize the importance of male participation in determining the outcome of nests for species exhibiting bi-parental care. Furthermore, woodland habitats previously considered marginal may be good quality habitat in areas with large populations of black-capped vireos. Recognizing woodlands as non-typical, yet still suitable, habitat will allow managers to incorporate these vegetation types into management plans and recommendations for landowner conservation incentive programs.

There is more human-generated noise and light today than ever before, a trend tied to ongoing urbanization and with reverberating impacts on a wide range of organisms. While research on these impacts is mounting and particularly plentiful when it comes to birds, there is still much to explore within its effects on avian behavior, fitness, and evolution. In chapter 1, we investigated how fledgling movement is influenced by noise and light pollution. While adult birds have well-documented species-specific responses to these stimuli, fledglings are sorely understudied in this context. We experimentally manipulated light levels and took advantage of an existing landscape of artificial noise in the gas fields of northwestern New Mexico to radio track fledglings through gradients of noise and light from four species: Western bluebirds (Sialia mexicana), mountain bluebirds (Sialia currucoides), ash-throated flycatchers (Myiarchus cinerascens), and gray flycatchers (Empidonax wrightii). Step-selection functions assessing resource selection and generalized additive models assessing step length, step velocity, and distance from nest showed no influence of noise and light pollution on fledgling movement, but did show that ash-throated flycatchers moved further each day and further from the nest than gray flycatchers. Our results also revealed the novel pattern of fledglings moving away from the nest through day 10 of the radio tracking period, but moving back towards it after day 20. While we did not find positive results for our primary question, these observations of fledgling movement are valuable given how little we know about this vulnerable life stage. In chapter 2, we investigated whether dim light vision and its corresponding bony structures within the eye could be under selection with the proliferation of artificial light, given that variation in avian responses to light pollution was recently linked to the quality of a bird's dim light vision. We used museum specimens of six urban adapted species collected across 100+ years and light pollution proxies in the form of collection year and urban density to test two alternative hypotheses. Under the protection hypothesis, selection should drive evolution of poorer dim light vision with higher light pollution exposure, decreasing fitness cost borne via the hormone and circadian rhythm dysregulation associated with retinal-received light pollution. Under the temporal niche shift hypothesis, prolonged foraging opportunities made accessible to birds that can better detect light in artificially lit conditions should drive evolution of improved dim light vision with light pollution exposure. We found that dim light vision improved with collection year for great horned owls (Bubo virginianus) while the opposite was true for red-tailed hawks (Buteo jamaicensis); surprisingly, house sparrows (Passer domesticus) and American crows (Corvus brachyrhynchos) showed support for both hypotheses within single species, exhibiting different directionality in dim light vision patterns for different light pollution proxies. Our results suggest that light pollution may represent a contemporary selective agent for avian vision, but that the directionality may depend on ecological context. More broadly, our findings suggest that quantifying animal perceptual abilities may be important for understanding inter-specific responses to an increasingly bright world.

This project argues that Octavia's Butler's construction of the black woman characters is unique within the pantheon of late eighties African-American writers primarily through Butler's celebration of black female physicality and the agency the black body provides. The project is divided into five sections beginning with an intensive examination of Butler's ur-character, Anyanwu. This character is vitally important in discussing Butler's canon because she embodies the attributes and thematic issues that run throughout the author's work, specifically, the author's argument that black woman are provided opportunity through their bodies. Chapter two addresses the way black women's femininity is judged: their sexual activity. In this chapter, I explore one facet of Octavia Butler's narrative examination of sexual co-option and her subsequent implied challenge to definitions of feminine morality through the character Lilith who appears throughout Butler's Xenogenesis trilogy. Specifically, I explore this subject using Harriet Jacobs' seminal autobiography and slave narrative, Incidents in the Life of a Slave Girl as the prism in which I historically focus the conversation. In chapter three, I move the discussion into an exploration of black motherhood. Much like the aforementioned challenge to femininity vis-à-vis sexual morality, Octavia Butler often challenges and interrogates the traditional definition of motherhood, specifically, the relationship between mother and daughter. I will focus on different aspects of that mother/daughter relationship in two series, the Patternist sequence, which includes, in chronological order, Wild Seed, Mind of my Mind and Patternmaster. Chapter four discusses Butler's final novel, Fledgling, and how the novel's protagonist, Shori not only fits into the matrix of Butler characters but represents the culmination of the privileging of black female physicality that I observe in the author's entire canon. Specifically, while earlier characters are shown to create opportunities and venues of agency through their bodies, in Shori, Butler posits a character whose existence is predicated on its blackness and discusses how that purposeful racial construction leads to freedom. / English

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