Modeling Fine-scale Avian Distributions and Densities with Multi-scale Models: Predicting the Past and Present

Models of a species’ distribution and models of a species’ spatially explicit density are valuable tools for conservation. They allow researchers to estimate changes in distributions, densities, and populations, based on changing environmental conditions. To trust such estimates, however, the quality of models is exceedingly important. Model performance can be affected by the scale at which the environment is characterized, species-specific characteristics such as prevalence and habitat specialization, or the quality of data collected. High-quality models of current distributions and densities can be used to assess the current status of species over a study extent. With environmental data extrapolated to the past or future, such models can be used to predict changes in species status through time. In Chapter 2, I developed and assessed multi-scale models of species distribution and abundance using the boosted regression tree algorithm. Multi-scale species distribution models consistently performed as well or better than best single-scale models. This multi-scale framework greatly reduces the number of models necessary to account for species’ response to environmental scale and avoids potential mischaracterization of important environmental scales. Hurdle models of abundance, however, performed poorly throughout the study. Fine-scale abundance is more difficult to model accurately than occurrence. Alternative methods may be more appropriate. In Chapter 3, I examined the comparative roles of species’ prevalence, sample size, and habitat specialization, on the performance of species distribution models. Although all three affected model performance, the role of prevalence was minor compared to the role of habitat specialization. I found a species-specific quadratic effect of sample size on model performance where generalist species required larger minimum sample sizes for accurate models. I then used my findings to recommend minimum sample sizes based on habitat specialization. In Chapter 4, I examined the use of occurrence and abundance data from the eBird database for fine-scale species distribution and density modeling. I compared the results of distribution and density models built on eBird data to the results of models built on highly standardized surveys from the Oregon 2020 project. To convert observed abundances in eBird to densities, I used estimates of detection probability from the Oregon 2020 data. Overall, the results of distribution and density models from the two datasets were very similar. I explore the reasons for differences and give guidelines for how to best use eBird data in fine-scale distribution and density modeling. In Chapter 5, I modeled current and historic distributions and densities of seven species of bird in the Willamette Valley, Oregon. I used reconstructed 1850s habitat data to hind-cast densities and distributions to pre-European-American settlement throughout the study area. I estimated current and historic populations for each species as well. I found population declines exceeding declines in suitable grassland and oak habitats for grassland and oak specialists. I found relatively stable populations and suitable habitat for riparian and edge specialists and increases in population and suitable habitat for species associated with coniferous forests. Hind-casted distributions and densities can provide a new baseline for the effects of anthropogenic habitat change on bird populations in the Willamette Valley. My research aims to better the understanding of species distribution and density modeling. I address important topics from the scale at which environmental variables should be characterized to the minimum sample sizes for accurate models and the species’ characteristics that affect that sample size. I build guidelines for fine-scale distribution and density modeling with the popular rapidly growing citizen science eBird database. Finally, I use fine-scale multi-scale models to estimate historic distributions and populations that provide a new baseline for change since European-American settlement

Multidimensional Approach to Comparative Avian Visual Systems

Since the birth of visual ecology, comparative studies on how birds see their world have been limited to a small number of species and tended to focus on a single visual trait. This approach has constrained our ability to understand the diversity and evolution of the avian visual system. The goal of this dissertation was to characterize multiple visual dimensions on bird groups that are highly speciouse (e.g., Passeriformes), and test some hypotheses and predictions, using modern comparative tools, on the relationship between different visual traits and their association with visual information sampling behaviors. First, I developed a novel method for characterizing quantitatively the retinal topography (e.g., variation in cell density across the retina) of different bird species in a standardized manner. Second, using this method, I established that retinal configuration has converged particularly in terrestrial vertebrates into three types of retinal specializations: fovea, area, and visual streak, with the highest, intermediate, and lowest peak and peripheral ganglion cell densities, respectively. The implication is that foveate species may have more enhanced visual centers in the brain than non-foveate vertebrates. Third, forest passerines that form multi-species flocks and belong to an insectivore niche differ in their visual system configuration, which appeared associated to behavioral specializations to enhance foraging opportunities: species that searched for food at steep angles had relatively wide binocular fields with a high degree of eye movement right above their short bills, whereas species that searched for food at shallower angles had narrower binocular fields with a high degree of eye movement below their bills. Eye movement allows these species to move their fovea around to visually search for food in the complex forest environment. Fourth, I studied the visual system configuration of nine species of closely related emberizid sparrows, which appear to maximize binocular vision, even seeing their bill tips, to enhance food detection and handling. Additionally, species with more visual coverage had higher visual acuity, which may compensate for their larger blind spots above their foveae, enhancing predator detection. Overall, the visual configuration of these passive prey foragers is substantially different from previously studied avian groups (e.g., sit-and-wait and tactile foragers). Finally, I studied the visual system configuration and visual exploratory behavior of 29 North American bird species across 14 Families. I found that species with a wider blind spot in the visual field (pecten) tended to move their heads at a higher rate probably to compensate for the lack of visual information. Additionally, species with a more pronounced difference in cell density between the fovea and the retinal periphery tended to have a higher degree of eye movement likely to enhance their ability to move their fovea around to gather high quality information. Overall, the avian visual system seems to have specializations to enhance both foraging and anti-predator behaviors that differ greatly between species probably to adjust to specific environmental conditions

An Ecological Study of the Vertebrates of a Streambank Community in Ellis County, Kansas

This investigation was conducted on Big Creek near Hays, Kansas. The study area, in the mixed-prairie association, is in the post-climax stage of succession. The principal plants of the area were: American elm, green ash, catalpa, Virginia wild rye, giant ragweed and western wheatgrass. The principal purpose was to make a complete list of the vertebrates, and to describe, as far as the data permitted, their ecological roles in the study area. Several methods were employed to sample the various populations. Amphibians were collected by hand, reptiles by means of barrier traps, and small mammals by snap traps. In the case of birds and large mammals observations and other indications of their presence was the only means of identification. A total of 165 amphibian specimens representing six species, five genera, four families and two orders was collected. The reptiles were composed of 15 specimens representing 16 species, 14 genera, and five families. Ninety species of birds representing 10 genera, 69 families and 12 orders were observed. In the case of the small mammals, 218 specimens were captured in a total of 2160 trap nights representing seven species. Large mammals present in the area either permanently or sporadically were composed of 14 species, 13 genera, nine families and five orders. Considerable information pertaining to food habits, habitat preference, and seasonal migrations was recorded

Songbird ecology in Southwestern Forest Service ponderosa pine forests: A literature review

This publication reviews and synthesizes the literature about ponderosa pine forests of the Southwest, with emphasis on the biology, ecology, and conservation of songbirds. Critical bird-habitat management issues related to succession, snags, old growth, fire, logging, grazing, recreation, and landscape scale are addressed. Overviews of the ecology, current use, and history of Southwestern ponderosa pine forests are also provided. This report is one of the outcomes of the Silver vs homasco urt-settlement agreement of 1996. It is intended for planners, scientists, and conservationists in solving some of the controversies over managing forests and birds in the Southwest

Habitat relationships of boreal forest birds in managed mixedwood forests.

Disturbance ecology suggests that if patterns created by boreal harvesting more closely resemble effects of natural disturbance, then boreal birds should more easily cope with habitat changes associated with harvesting. I tested this idea by documenting avian community responses to partial-cutting treatments applied in Fort Nelson, British Columbia. The purposes of this study were threefold: 1) to investigate changes in the bird community following partial-cutting in boreal forest stands; 2) to compare point-count and transect bird survey methods and determine the degree of correlation between the two datasets; and 3) to test the applicability of bird-habitat models developed in Alberta\u2019s boreal forest for predicting species abundance in a boreal forest environment in northern British Columbia. Two bird survey protocols, point-counts and fixed-width transects, were employed in 4 partial-cut and 2 uncut (control) stands. Each stand was surveyed 4 times per season over 2 breeding seasons. Detailed habitat information was collected in 212-0.04 ha plots. Similar numbers of species were observed in each year with 50 and 52 species observed in 1999 and 2000, respectively. More than half (51.7%) the total species observed were neotropical migrants. Differences in cumulative species per point count station between years were not explained by treatment effect. There were differences in species distribution across sites with mourning warbler and Connecticut warbler consistently detected only at the partial-cut sites in both years. None of the detected bird species occurred only at the control sites when data for both years was combined; however, in each year there were 3 different rare species detected only at the uncut sites. Species diversity differed between partial-cuts and controls and between years. Significant correlations between the two survey methods depended on bird species, habitat and timing of survey in the breeding season (i.e., early or late in the season). For the bird-habitat model comparison, models containing local and neighbourhood habitat variables were generated for 13 candidate boreal forest bird species. There was a lack of agreement between predicted species abundances and those observed.The original print copy of this thesis may be available here: http://wizard.unbc.ca/record=b128529

Bulletin of the Center for Children's Books 50 (09) 1997

published or submitted for publicatio

North Campus Open Space Restoration Project Annual Monitoring Report: Year 2 (2019)

Born out of a vision shared by the local community, students, faculty, researchers and state and federal agencies, the North Campus Open Space (NCOS) restoration project is recreating more than 40 acres of estuarine and palustrine wetlands that historically comprised the upper portion of Devereux Slough that was filled in the mid-1960s to create the Ocean Meadows golf course. Led by the UC Santa Barbara Cheadle Center for Biodiversity and Ecological Restoration (CCBER) in collaboration with other UCSB departments, faculty, student and local community groups, contractors and government agencies, the project is also restoring more than 60 acres of upland habitats that include native grassland, coastal sage scrub, riparian, oak chaparral woodland, vernal pools and patches of annual wildflowers in clay and sandy soils. In addition to wetland and upland habitat restoration, the goals of the NCOS project include flood reduction, support for threatened and endangered species, public access and the provision of educational opportunities. Ancillary benefits of the project include carbon sequestration, preservation of local genotypes, and protection of adjacent ecological values and infrastructure through a design that integrates sea level rise considerations.Currently in its third year of implementation, the main planting phase of the project is approximately 90% complete, and the focus is now turning towards maintenance, continued monitoring, new research projects, and supplemental planting to add diversity, including special status species such as the Ventura marsh milk-vetch (Astragalus pycnostachys var. lanosissimus). This report describes the methods and results of monitoring for the first two years of the project, from vegetation and wildlife to wetland geomorphology, hydrology and water quality, carbon sequestration studies, community use and a detailed record of restoration efforts by type of worker, task and site location. This work documents the progress of the project and supports longer-term research and monitoring programs. Results from the second year of monitoring show substantial progress towards the project’s restoration goals, with many being met or exceeded

Picturing Nature: Education, Ornithology and Photography in the Life of Cordelia Stanwood: 1865-1958

The field of environmental history, with a few exceptions, has neglected gendered analysis; in addition, several women\u27s histories have analyzed a few environmental issues, but disregard environmental scholarship. In the joining of women\u27s and environmental history, this dissertation examines the life of one woman, Cordelia J. Stanwood of Ellsworth, Maine (1865-1958), to determine how a woman could use nature to transcend the social limits of domesticity in the early twentieth century. Research of her correspondence, published writing, photography and forty years of field notes reveals that like many other women, she took advantage of technology and evolving ideas about womanhood in order to maintain her autonomy. Most important, she pioneered in bird life history and photography for ornithologists, in the process commodifying nature for her economic support. Stanwood\u27s life as a naturalist began upon her return home to Ellsworth, Maine at the end of a nineteen-year teaching career in which she practiced nature study in the service of art instruction in the public schools. Once in Ellsworth, she became renown for her I ornithological expertise, conducting bid studies from 1904 until 1922. She contributed new findings to ornithology and broke new ground with the bird photograph. In an era of limited professional opportunities for women, she crafted a second career as a pathbreaking nature photographer, writer, and environmental advocate. Following the publication of her scientific ornithology, Stanwood pioneered the illustrated popular ornithology article. Stanwood\u27s bird life histories make her a transitional figure in the history of ornithological writing, and her bird photographs inspired the generation of nature photographers that followed her. Stanwood distinguished herself in her work for bird conservation as a professional ornithologist, setting herself apart from mainstream female club lady conservation reformers. She shares a genre of writing with other women in her scientifically oriented writing and photography, contributing original scientific work adapted to the popular audience during a period of proliferating print and visual media At the end of her life, Stanwood donated her house, papers, and land as a house museum and sanctuary, foreshadowing the increasingly popular land conservation ethic that is widespread today

Sustaining biological diversity in managed sub-boreal spruce landscapes: Residual habitat strategies for cavity nesting species.

No abstract available.The original print copy of this thesis may be available here: http://wizard.unbc.ca/record=b119451