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Full-Text Articles in Biology

Temperature Affects Nest Box Occupancy, Nest Success, And Nestling Size In A Southeastern Population Of Eastern Bluebirds (Sialia Sialis), Christopher G. Horacek Nov 2022

Temperature Affects Nest Box Occupancy, Nest Success, And Nestling Size In A Southeastern Population Of Eastern Bluebirds (Sialia Sialis), Christopher G. Horacek

Biology Theses

Given the critical role that temperature plays in avian reproductive biology, rising temperatures as a result of global climate change will likely impact reproductive success of many bird populations. Secondary cavity nesting birds, many of which rely on artificial nest boxes to maintain population levels, may be particularly at risk because increased temperatures inside nest boxes can determine whether nest boxes are selected, reduce nest success, and/or negatively affect the growth and survival of offspring. We examined the effect of nest box color on nest box temperature and the influence of nest box temperature, nest box color, entrance orientation, and …


Insights Into The Speciation Process From Genomic And Phenotypic Analysis Of An Avian Hybrid Zone In Amazonia, Glaucia Christina Del-Rio Jul 2022

Insights Into The Speciation Process From Genomic And Phenotypic Analysis Of An Avian Hybrid Zone In Amazonia, Glaucia Christina Del-Rio

LSU Doctoral Dissertations

Understanding the outcome of secondary contact is essential to shed light on the mechanisms governing species formation and maintenance. In Amazonia, closely related bird taxa with limited dispersal abilities are often separated by rivers, which presumably act as dispersal barriers. However, at the headwaters, rivers cease to be dispersal barriers, and this generates opportunities for secondary contact. In my dissertation, I studied genomic mechanisms associated with phenotypic differences, mitochondrial DNA structure, and putative reproductive barriers between two hybridizing Amazonian bird species in the genus Rhegmatorhina, a group of antbirds that find their arthropod prey exclusively by following army-ant swarms. …


A Review Of Current Methods In Avian Dietary Analysis And Their Integrated Application To Characterize The Trophic Niche Of Louisiana Waterthrush (Parkesia Motacilla)., Brandon Hoenig May 2022

A Review Of Current Methods In Avian Dietary Analysis And Their Integrated Application To Characterize The Trophic Niche Of Louisiana Waterthrush (Parkesia Motacilla)., Brandon Hoenig

Electronic Theses and Dissertations

Characterizing a species’ dietary composition presents an avenue to understand many facets of its ecological niche and can provide essential information for the species’ long-term conservation. To date, the vast majority of diet studies have relied on direct identification of prey during foraging observations or from diet samples to characterize the dietary habits of birds. However, advancements in laboratory-based approaches have revolutionized the field of trophic ecology by allowing researchers to indirectly infer dietary habits with higher resolution across greater time scales. Here, I apply two of these laboratory-based techniques, namely DNA metabarcoding and stable isotope analysis, to characterize the …


Sex Ratios And The City: Is Parental Corticosterone A Mediator Of The Relationship Between Urbanization And Offspring Sex Allocation?, Denyelle Kilgour Apr 2022

Sex Ratios And The City: Is Parental Corticosterone A Mediator Of The Relationship Between Urbanization And Offspring Sex Allocation?, Denyelle Kilgour

Master of Science in Integrative Biology Theses

The Trivers-Willard hypothesis states that mothers can adjust their offspring sex ratios according to their own condition and the environmental conditions they face during breeding. Past tests of this hypothesis in avian species have focused on how natural variation shapes sex allocation trade-offs. However, urbanization also influences individual condition and presents animals with novel challenges in optimizing their brood sex ratio. One likely mediator of the relationship between environmental conditions, parental condition, and sex ratios is corticosterone (CORT), the primary glucocorticoid in birds. However, no research has examined the links between urbanization, individual condition, CORT, and adaptive sex allocation within …


Drivers And Direct Impacts Of Lean Mass Dynamics On The Stopover Ecology And Migratory Pace Of Nearctic-Neotropical Migrant Songbirds In Spring, Mariamar Gutierrez Ramirez Mar 2022

Drivers And Direct Impacts Of Lean Mass Dynamics On The Stopover Ecology And Migratory Pace Of Nearctic-Neotropical Migrant Songbirds In Spring, Mariamar Gutierrez Ramirez

Doctoral Dissertations

Annual migration in songbirds is one of the most demanding life-history stages. It represents a period of high mortality, yet there is still much unknown about the ecological correlates that influence its successful completion. After long non-stop migratory flights, birds require a stopover period to rest and replenish depleted energy reserves. Birds use fat as the primary fuel to power long-distance flights. However, birds also burn lean tissue, which results in significant reductions in muscle and organ masses. The discovery and quantification of lean mass catabolism represented a paradigm shift in migration ecology because non-fat components were thought to remain …


Display Site Selection By Male Ruffed Grouse In The Upper Great Lakes Region, Seth Finkel Jan 2022

Display Site Selection By Male Ruffed Grouse In The Upper Great Lakes Region, Seth Finkel

Dissertations, Master's Theses and Master's Reports

The Ruffed Grouse (Bonasa umbellus) is widely known for its characteristic territorial drumming display. In this study, I used ruffed grouse drumming survey data from Minnesota and Michigan, in a series of mixed logistic models, to identify drivers of drumming log selection by reproductive male ruffed grouse. I collected drumming stage data utilizing a paired-random sampling structure. I used information theoretic model selection to examine three sets of a priori mixed logistic models: one for the entirety of my Minnesota dataset, one consisting of stages identified in aspen stands in Minnesota, and one for my Michigan dataset. In …


Influences Of Grazing On Habitat Characteristics, Avian Community Composition And Nesting Bird Abundance Within Cheyenne Bottoms, Ks, Kirsten Granstrom-Arndt Jan 2022

Influences Of Grazing On Habitat Characteristics, Avian Community Composition And Nesting Bird Abundance Within Cheyenne Bottoms, Ks, Kirsten Granstrom-Arndt

Master's Theses

Cheyenne Bottoms is a 41,000-acre prairie-marsh ecosystem in central Kansas. Approximately 8,000 acres of mixed grassland are dedicated for the conservation of bird populations, but little is known about the status of bird communities within these areas. This study took place within grassland areas of Cheyenne Bottoms from May – July 2021. I investigated bird community composition, relative abundance of frequently observed bird species, vegetative characteristics, and similarity of sites across different grazing intensities (continuous, rotational, and non-grazed). The four most common bird species observed were dickcissel (Spiza americana), grasshopper sparrow (Ammodramus savannarum), meadowlark species ( …