Ornithology Commons^™

The Impacts Of Wing-Flashing By Northern Mockingbirds On Foraging, Parental Care, And Reproductive Success, Anna R. Starman

Undergraduate Honors Theses

Foraging efficiency may be enhanced by flashing patches of white wing and tail feathers and has been documented in several avian species. Northern Mockingbirds (Mimus polyglottos, NOMO) exhibit this “wing-flashing” (WF) behavior while foraging, during displays, and in response to predators. In NOMOs, WF has been hypothesized to increase foraging success, but previous findings are inconclusive. To further investigate the biological role(s) of WF behavior in NOMOs, the ventral surface of white primary feathers of male NOMOs were artificially darkened, and the foraging and provisioning rates of undarkened (control) males and their mates were compared. While foraging, undarkened …

Data From: Mass Mortality Of Avian Migrants In New Mexico, Usa, That Coincided With An Extreme Weather Event, Dylan M. Osterhaus, Allison J. Salas, Patricia L. Cutler, Mara E. Weisenberger, Kerry Mower, Abigail J. Lawon, Timothy F. Wright, Jeanne M. Fair, Martha J. Desmond

Fish, Wildlife, & Conservation Ecology: Datasets

No abstract provided.

A Silver Spoon Effect Reduces Lifetime Fitness In A Declining Loon Population, Walter H. Piper, Claudia Kodsuntie, Hayden Walkush

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A complete understanding of factors that influence animal fitness requires that we measure not only those occurring day to day in the life of an animal but also those that operate on longer time scales. Here, we investigated silver spoon effects (fitness impacts resulting from conditions faced early in life) and carryover effects (fitness impacts caused by environmental factors in a previous season) in a northern Wisconsin population of the common loon (Gavia immer). The mass of a loon chick divided by its age, an indication of food it received from its parents in its first 4 to …

The Effect Of Noise Pollution On The Diversity And Abundance Of Bird Species At Different Locations At Warner Parks, Nashville, Tn, Jeremy T. Little, Wyatt L. Fooks, Darlene Panvini, Jackson Whiteside

Science University Research Symposium (SURS)

Noise pollution is a significant abiotic factor that can alter bird biodiversity and abundance of birds in urbanized areas. A new road is proposed through a relatively untouched area of Warner Parks in Nashville, TN, which may affect the bird community. Acoustic Song Meters were used to monitor bird sounds and soundscapes in the proposed road site and two areas of the park with different levels of noise pollution (roadside=high noise; isolated=low noise) for three weeks. Recordings were analyzed to determine bird species and abundance at each site to predict how increasing noise pollution may affect bird diversity in the …

Examining The Effects Of Songbird Nest Boxes And Habitat On Avian And Arthropod Communities In A Vineyard Ecosystem, Eleanor Macdonald

Cal Poly Humboldt theses and projects

Agricultural expansion threatens biodiversity, but integrating insectivorous birds into vineyard ecosystems may support both conservation and ecosystem services. We tested how nest boxes and habitat composition influence avian and arthropod communities in Napa Valley vineyards using a before-after, control-impact experiment across 20 sites. During the 2023-2024 breeding seasons we conducted avian point counts, sampled key pest and beneficial arthropods, and collected fecal samples from adult and nestling tree swallows (Tachycineta bicolor) and western bluebirds (Sialia mexicana) to detect vineyard pest DNA. Nest boxes significantly increased swallow and bluebird abundance within one year; swallow responses were strongest …

Habitat Loss And Its Behavioral Effects On A Female Gray Hawk In The Lower Rio Grande Valley Of Texas, Usa, Michael T. Stewart, Ashley M. Tanner, Brian A. Millsap, William S. Clark

Human–Wildlife Interactions

Habitat loss is a major threat to wildlife worldwide. While habitat loss is commonly associated with the fragmentation, degradation, or destruction of large tracts of suitable space, habitat loss in urban environments can be much more incremental and nuanced. We tracked an adult female gray hawk (Buteo plagiatus) in the Lower Rio Grande Valley of Texas, USA, before and after 70% of the trees (7.6 ha) were cleared from the core of the nesting territory. While the hawk’s overall activity budget between within-patch and exploratory movements was unchanged, the hawk undertook substantially longer exploratory movements after the trees …

The Role Of Elevation In The Migration, Physiology, And Genomic Diversification Of Birds, Jessie L. Williamson

Biology ETDs

Elevational gradients cause profound eco-climatic variation across short distances. Partial pressure of oxygen (PO₂) is a severe challenge that organisms face at high elevations; due partly to specialization on PO₂, most Neotropical bird species have narrow elevational ranges. However, a small fraction are elevational generalists that span sea level to high elevations, and a subset undertake extreme migratory journeys from low to high elevations biannually. My dissertation combines diverse approaches across levels of biological organization to understand how elevation impacts the ecology, evolution, physiology, and migration of montane birds. I examined ‘extreme’ elevational …

Avian Symbionts Of Sulawesi: Identifying And Correlating Malaria Parasites And The Microbiome In Communities Of Endemic Avian Hosts, Rachael Joakim

Dissertations, Theses, and Capstone Projects

Since the evolution of complex organisms, there have been communities of symbionts inhabiting them. Thanks to the development of parallel sequencing techniques, DNA of entire microbial communities can be sequenced from a single sample. Some microbes can be parasitic in nature, such as Haemosporida, an order of eukaryotes causing malaria. While most symbionts form a more commensal host relationship in wild systems, host-symbiont dynamics can vary in pathogenicity based on biotic and abiotic factors. In vertebrates, microbial communities in the gut play a major role in host function, including immune responses to Haemosporida. Though this relationship is most commonly explored …

Characterization Of Antimicrobial Properties Of Excrement And Functional Microbiome Of Black Vultures (Coragyps Atratus), Bridgette Gray

Theses

Black vultures, Coragyps atratus, are obligate scavenging birds that consume and dispose of decaying carcasses and carrion. They fulfill a key ecological niche in the environments in which they live. It has been observed that these vultures sometimes excrete bodily waste onto their legs. This adaptive behavior could help aid them in controlling bacteria and other microbes they encounter while stepping into a carcass to eat. This study directly examined the antimicrobial properties of the excrement of black vultures across various bacterial species utilizing a zone of inhibition test and a nematode species utilizing a survival assay. The black vulture …

The Role Of Interspecific Competition In The Range Collapse Of A Songbird After Rapid Range Expansion, Zachary H. Vickers

Graduate Theses/Dissertations

There is a wealth of evidence demonstrating interspecific competition in birds, but often this evidence is localized and may or may not entirely explain range dynamics over large geographic extents. Bewick’s Wrens (Thrymanes bewickii) and House Wrens (Troglodytes aedon) are small passerine birds of the family Troglodytidae. Previous experimental evidence has demonstrated that Bewick’s Wrens suffer from asymmetric interference competition from House Wrens in Kansas, and this evidence has been cited as the likely reason for the historically recent range collapse of the Bewick’s Wren. However, I argue that localized experimental evidence is insufficient to explain abundance trends over large …

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 …

The Role Of Nest Location On The Reproductive Success Of Piping Plovers Breeding At Rockaway Beach, New York, Clara I.D. Arndtsen

Theses and Dissertations

The study’s goal was to learn what aspects of the piping plover experience affect reproductive outcomes at Rockaway Beach Endangered Species Nesting Area. Nest location was found to help predict reproductive success. Nests further from American oystercatcher nests were likely to fledge more chicks. Reproductive success was low in 2021.

Maternal Responses In The Face Of Infection Risk, Patricia C. Lopes, Brenna M. G. Gormally, Aubrey Emmi, Delilah Schuerman, Chathuni Liyanage, Ursula K. Beattie, L. Michael Romero

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

When animals are sick, their physiology and behavior change in ways that can impact their offspring. Research is emerging showing that infection risk alone can also modify the physiology and behavior of healthy animals. If physiological responses to environments with high infection risk take place during reproduction, it is possible that they lead to maternal effects. Understanding whether and how high infection risk triggers maternal effects is important to elucidate how the impacts of infectious agents extend beyond infected individuals and how, in this way, they are even stronger evolutionary forces than already considered. Here, to evaluate the effects of …

Effects Of Melatonin Implantation On The Activity Levels Of Captive Snow Buntings (Plectrophenax Nivalis), Zoë Ward

Mahurin Honors College Capstone Experience/Thesis Projects

In vertebrates, melatonin regulates many components of the circadian rhythm; depending on the organism’s location and time of year, the pineal gland will produce melatonin accordingly, controlling the sleep-wake cycle and breeding physiologies. However, locations at the poles in which the sun is above the horizon for multiple days at a time pose unique challenges for the organisms living there. The goal of this study was to examine how the implantation of melatonin in an arctic-breeding songbird affects its activity levels and circadian rhythm. The subject of this study, the snow bunting (Plectrophenax nivalis), is a small songbird …

Epigenetic Buffering In Introduced House Sparrows, M. Ellesse Lauer

College of Graduate Studies: Theses & Dissertations

Epigenetic buffering, as an environmentally induced increase in variance of epigenetic states that increases phenotypic variation to buffer populations against decreased fitness, may be a factor that resolves the genetic paradox of introduced species. DNA methylation is a molecular mechanism that could facilitate epigenetic buffering by changing in response to environmental stress. Therefore, epigenetic buffering can be detected through increased variance in DNA methylation in novel or heterogeneous environments. Introduced house sparrows (Passer domesticus) have well-documented phenotypic changes with low genetic diversity, high epigenetic diversity, and high variance in DNA methylation that provide a characteristic signature of epigenetic buffering. …

Brood Abundance And Invertebrate Availability In Crop-Dominated Landscapes In The Prairie Pothole Region, Catrina V. Terry

LSU Master's Theses

The Prairie Pothole Region (PPR) is the most important region for ducks in North America, producing over half the ducks on the continent, and it is a priority landscape for wetland and grassland conservation. Agricultural expansion has changed the PPR, and the majority of grasslands and potholes have been converted into row-crops. The loss of nesting habitat has directly caused nest success to decline. Most of the remaining wetlands are surrounded by row-crops, and are considered lower quality because they receive runoff of sediment and chemicals, which may decrease primary forage for young ducklings as well as inhibit wetland vegetation. …

Vertebrate Scavenger Diversity And Ecosystem Services Along An Elevational Gradient In Central Nepal, Aishwarya Bhattacharjee

Dissertations, Theses, and Capstone Projects

A growing number of studies recognize the ecological significance of vertebrate scavengers, and several species belonging to this diverse, functional guild are of high conservation importance around the globe. Studies on taxonomic and functional components of biodiversity often use elevation gradients to comprehensively examine patterns and drivers across multiple spatial scales. Yet, there are relatively few elevational studies on large vertebrates or multi-taxa guilds, and the related variation of their ecosystem services. In particular, scavenger research has largely focused on local-scale studies or regional/global comparisons of local-scale investigations. Moreover, these studies primarily consider taxonomic community characteristics and the patterns of …

Seasonal Plumage Condition Variation And The Thermal Value Of The Feather Coats Of House Sparrows (Passer Domesticus), Jordana Mf Graveley, Margaret Rubega, Kevin R. Burgio

Honors Scholar Theses

Feathers are critical to how birds thermoregulate, and thus their total energy balance. The feather coat insulates birds by trapping air next to the skin and acting as a physical barrier to heat loss. Despite previous work studying thermal balance in birds, relatively few studies have focused on the thermal contribution of the feather coat alone; most studies have focused on physiological and behavioral responses. Moreover, to our knowledge, no studies have directly measured the effect of feather wear through the annual cycle on the thermal performance of the feather coat. To address this, we used a thermal camera to …

Common Ravens Disrupt Greater Sage-Grouse Lekking Behavior In The Great Basin, Usa, Joseph L. Atkinson, Peter S. Coates, Brianne E. Brussee, Ian A. Dwight, Mark A. Ricca, Pat J. Jackson

Human–Wildlife Interactions

Expansion of human enterprise has contributed to increased abundance and distribution of common ravens (Corvus corax; ravens) across sagebrush (Artemisia spp.) ecosystems within western North America. Ravens are highly effective nest predators of greater sage-grouse (Centrocercus urophasianus; sage-grouse), a species of high conservation concern. Sage-grouse population trends are estimated using count survey data of males attending traditional breeding grounds, known as leks. We sought to investigate associations of ravens to sage-grouse lek sites and document interactions between the sage-grouse and ravens as well as those between sage-grouse and other animals observed around leks. First, we …

Synthesis Of Nest Predation Impacts Of Common Ravens On Sensitive Avian Species, Peter S. Coates, William C. Webb, Seth J. Dettenmaier, Seth M. Harju, David J. Delehanty

Human–Wildlife Interactions

Decades of mounting scientific evidence have revealed that common raven (Corvus corax; raven) population numbers have been increasing across nearly all regions of their geographic range in North America. Concomitantly, numerous native wildlife species have experienced elevated predation rates from ravens as populations have increased and expanded their range. Managers are concerned that increased raven predation of many threatened and endangered avian species in the U.S. and Canada during nesting periods may be hampering species recovery. We explored the literature to aggregate existing knowledge and evaluate the impacts of raven predation on nests and young of sensitive avian …

A Decision Tool To Identify Population Management Strategies For Common Ravens And Other Avian Predators, Andrea F. Currylow, Brenda J. Hanley, Kerry L. Holcomb, Timothy Shields, Stephen Boland, William I. Boarman, Mercy Vaughn

Human–Wildlife Interactions

Some avian species have developed the capacity to leverage resource subsidies associated with human manipulated landscapes to increase population densities in habitats with naturally low carrying capacities. Elevated corvid densities and new territory establishment have led to an unsustainable increase in depredation pressure on sympatric native wildlife prey populations as well as in crop damage. Yet, subsidized predator removal programs aimed at reducing densities are likely most effective longer-term when conducted in tandem with subsidy control, habitat management, and robust assessment monitoring programs. We developed decision support software that leverages stage structured Lefkovitch population matrices to compare and identify treatment …

Common Raven Impacts On The Productivity Of A Small Breeding Population Of Snowy Plovers, Matthew J. Lau, Benjamin H. Becker, David T. Press

Human–Wildlife Interactions

Common ravens (ravens; Corvus corax), an adaptable, synanthropic generalist, have thrived coincident with increasing human landscape modifications and fragmentation, consequently affecting their prey, which are often sensitive native and protected species. Ravens are a conservation concern for the protected western snowy plover (plover; Charadrius nivosus nivosus), causing low nest and chick survival in some breeding areas along the Pacific coast of North America. We used a long-term dataset from a breeding snowy plover monitoring program in Point Reyes National Seashore (PRNS) to investigate potential impacts of ravens on snowy plover nest and fledging success. Between 2002 and 2020, …

A Rapid Assessment Function To Estimate Common Raven Population Densities: Implications For Targeted Management, Brianne E. Brussee, Peter S. Coates, Shawn T. O'Neil, Seth J. Dettenmaier, Pat J. Jackson, Kristy B. Howe, David Delehanty

Human–Wildlife Interactions

Common raven (Corvus corax; raven) populations have increased over the past 5 decades within the western United States. Raven population increases have been largely attributed to growing resource subsidies from expansion of human enterprise. Concomitantly, managers are becoming increasingly concerned about elevated adverse effects on multiple sensitive prey species, damage to livestock and agriculture, and human safety. Managers could benefit from a rapid but reliable method to estimate raven densities across spatiotemporal scales to monitor raven populations more efficiently and inform targeted and adaptive management frameworks. However, obtaining estimates of raven density is data- and resource-intensive, which renders …

Evaluating Common Raven Take For Greater Sage-Grouse In Oregon’S Baker County Priority Conservation Area And Great Basin Region, Frank F. Rivera-Milán, Peter S. Coates, Jacqueline B. Cupples, Michael Green, Patrick K. Devers

Human–Wildlife Interactions

The common raven (Corvus corax; raven) is a nest predator of species of conservation concern, such as the greater sage-grouse (Centrocercus urophasianus). Reducing raven abundance by take requires authorization under the Migratory Bird Treaty Act. To support U.S. Fish and Wildlife Service’s take decisions (e.g., those that authorize killing a specified proportion or number of individuals annually in a defined area), including the most recent one for Oregon’s Baker County Priority Area for Conservation (PAC), we modeled raven population dynamics under hypothetical scenarios with take rates ranging from below to above the maximum sustained yield (MSY; …

Investigating The Avian Species Composition, Diversity, And Abundance Of Engelhorn Pond, Kiana Rose

Undergraduate Honors Theses

Central Washington University’s Engelhorn Pond contains important habitats for many organisms, particularly migratory birds, and is a valuable resource for students. However, little information is available about the wildlife inhabiting the pond. The pond’s discrete location means that many people are unaware of its existence. In addition, the pond is threatened by a number of anthropogenic sources, including chemical runoff, garbage, and feral cats. By using point counts, a common ornithological survey technique, I recorded the bird species present at the pond during all seasons of the year. I collected data using point counts during 13 visits from June of …

The Effect Of Shade Tree Species On Bird Communities In Central Kenyan Coffee Farms, Deven Kammerichs-Berke

Cal Poly Humboldt theses and projects

Shade coffee has been recognized as a well-studied example of a land-sharing management strategy that both creates habitat for tropical birds while also maintaining agricultural yield. Despite the general consensus that shade coffee is more “bird-friendly” than a sun coffee monoculture, little work has been done to investigate the effects of specific shade tree species on bird diversity and their capacity to help deliver ecosystem services. Previous studies in temperate regions have demonstrated that due to shared evolutionary histories, native plant species are better at promoting native arthropod numbers, which in turn support a greater number of birds. This study …

The Evolution Of Dragons, Laura J. Mayfield

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Dragons have been depicted in human art as early as 4500 BCE. For centuries, these fantasy creatures have inspired countless folk and fantasy tales, as well as appearing in the art of different cultures around the world. Now there are thousands of different depictions of these huge, flying, fire-breathing lizards, but are any of them possible? In this study, I reference peer-reviewed scientific articles, phylogenetic analysis, and paleoart studies to create biologically-sound dragons. Basing the dragon lineage on a real branch of webbed-winged scansoriopterygids—an extinct family of climbing and gliding maniraptoran dinosaurs—I explored the possible wing-structure, fire-breathing abilities, and effects …

Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey R. Gadek

Biology ETDs

The distribution of life across the Andes mountains reflects historical elevational-range contraction and expansion. Whereas contraction implies specialization, expansion requires overcoming hidden barriers. Three eco-evolutionary phenomena may drive patterns in rates of elevational range evolution: (1) The Dobzhansky-MacArthur Phenomenon (DMP) predicts lower rates of upward expansion with harsher physical conditions, while downward expansion increases with lower diversity; (2) the evolutionary tendency toward specialization predicts contraction increases when ranges are broad; and (3) natural selection for respiratory performance could suppress expansion across mid-elevations due to gene-environment mismatch. We modeled elevational range shifts of Neotropical landbirds. Contrary to the DMP, upward expansion …

The Piping Plover Problem: A Review Of Management Issues For A Threatened Shorebird, Andrew Lydeard, Gerry Harris

Scholars Week

Andrew Lydeard and Gerry Harris

The Piping Plover (Charadrius melodus) was federally listed in 1986. Since listing, Piping Plovers have been a focus of conservation and management efforts, particularly on their breeding grounds in the Northern Great Plains, Great Lakes, and northern Atlantic Coast. Despite management efforts that have resulted in range-wide population growth of the Piping Plover, growth in individual populations is often slow and reasons for this are poorly understood. A bias towards understanding drivers of declines on breeding sites compared to wintering and migratory stopover sites may be an underlying cause of this lack of …

Tiger Sharks Eat Songbirds: Reply, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, A. E. Jefferson, A. M. Kroetz, Sean P. Powers, E. A. Seubert

University Faculty and Staff Publications

In response to our recent paper (Drymon et al. 2019), Yosef (2019) questions the mechanism proposed to explain interactions between tiger sharks (Galeocerdo cuvier) and migratory songbirds, while offering an alternative mechanism based on a single observation. We appreciate the comments from Yosef and the opportunity to respond.